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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 10-Q
(Mark One)
QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the quarterly period ended March 31, 2023
OR
TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from ___ to ___
Commission file number 001-40653
Duolingo, Inc.
(Exact name of registrant as specified in its charter)
Delaware45-3055872
(State or other jurisdiction of incorporation or organization)(I.R.S. Employer Identification No.)
5900 Penn Avenue
Pittsburgh, Pennsylvania 15206
(412) 567-6602
(Address, Including Zip Code, and Telephone Number, Including
Area Code, of Registrant’s Principal Executive Offices)
Securities registered pursuant to Section 12(b) of the Act:
Title of each classTrading Symbol(s)Name of each exchange on which registered
Class A common stock, $0.0001 per shareDUOL
 The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports); and (2) has been subject to such filing requirements for the past 90 days. 
Yes ☒ No ☐ 
Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).
Yes ☒ No ☐ 
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer”, “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
Large accelerated filerAccelerated filer
Non-accelerated filerSmaller reporting company
Emerging growth company
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes    No  ☒
As of May 8, 2023, 34,735,032 shares of the registrant's Class A common stock were outstanding, and 6,317,657 shares of the registrant's Class B common stock were outstanding.
1


Table of Contents
Page
1


Special Note Regarding Forward-Looking Statements
This Quarterly Report on Form 10-Q contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. We intend such forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in Section 27A of the Securities Act of 1933, as amended (the “Securities Act”) and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). All statements other than statements of historical facts contained in this Quarterly Report on Form 10-Q, including without limitation, statements regarding our business model and strategic plans, including the introduction of new brands or products, and our implementation thereof; statements regarding our expectations, beliefs, plans, objectives, prospects, assumptions, future events or expected performance, including our ability to compete in our industry; the sufficiency of our cash, cash equivalents and investments; and the plans and objectives of management for future operations and capital expenditures are forward-looking statements.
Without limiting the generality of the foregoing, you can identify forward-looking statements because they contain words such as “may,” “will,” “shall,” “should,” “expects,” “plans,” “anticipates,” “could,” “intends,” “target,” “projects,” “contemplates,” “believes,” “estimates,” “predicts,” “potential,” “goal,” “objective,” “seeks,” or “continue” or the negative of these words or other similar terms or expressions that concern our expectations, strategy, plans, or intentions. Such forward-looking statements are neither promises nor guarantees, but involve a number of known and unknown risks, uncertainties and assumptions that may cause our actual results, performance or achievements to differ materially from those expressed or implied in the forward-looking statements due to various factors, including, but not limited to:
our ability to retain and grow our users and sustain their engagement with our products;
competition in the online language learning industry;
our limited operating history;
our ability to achieve profitability;
our ability to manage our growth and operate at such scale;
the success of our investments;
our reliance on third-party platforms to store and distribute our products and collect revenue;
our reliance on third-party hosting and cloud computing providers;
our ability to compete for advertisements;
acceptance by educational organizations of technology-based education;
changes in business and macroeconomic conditions; and
those identified in Part I, Item 2. “Management’s Discussion and Analysis of Financial Condition and Results of Operations and Part II, Item 1A. “Risk Factors” in this Quarterly Report on Form 10-Q, and in Part II, Item 7. ““Management’s Discussion and Analysis of Financial Condition and Results of Operations” in our Annual Report on Form 10-K for the fiscal year ended December 31, 2022 (the “Annual Report on Form 10-K”).
We caution you that the foregoing list does not contain all of the forward-looking statements made in this Quarterly Report on Form 10-Q.
2


You should not rely upon forward-looking statements as predictions of future events. We have based the forward-looking statements contained in this Quarterly Report on Form 10-Q primarily on our current expectations, estimates, forecasts, and projections about future events and trends that we believe may affect our business, results of operations, financial condition, and prospects. These statements are based upon information available to us as of the date of this Quarterly Report on Form 10-Q and, although we believe that we have a reasonable basis for each forward-looking statement contained in this Quarterly Report on Form 10-Q, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. We cannot guarantee that the future results, levels of activity, performance, or events and circumstances reflected in the forward-looking statements will be achieved or occur at all. Moreover, we operate in a very competitive and rapidly changing environment. New risks and uncertainties emerge from time to time, and it is not possible for us to predict all risks and uncertainties that could have an impact on the forward-looking statements contained in this Quarterly Report on Form 10-Q. The results, events, and circumstances reflected in the forward-looking statements may not be achieved or occur, and actual results, events, or circumstances could differ materially from those described in the forward-looking statements. You should not place undue reliance on our forward-looking statements.
The forward-looking statements made in this Quarterly Report on Form 10-Q relate only to events as of the date on which the statements are made. While we may elect to update such forward-looking statements at some point in the future, we disclaim any obligation to do so, even if subsequent events cause our views to change.
You should read this Quarterly Report on Form 10-Q and the documents that we reference in this Quarterly Report on Form 10-Q completely and with the understanding that our actual future results may be materially different from what we expect. We qualify all of the forward-looking statements in this Quarterly Report on Form 10-Q by these cautionary statements.
Unless the context otherwise requires, all references in this Quarterly Report on Form 10-Q to “Duolingo,” the “Company”, “we,” “our,” “us,” or similar terms refer to Duolingo, Inc. and its subsidiaries.

3


Special Note Regarding Key Operating Metrics
We manage our business by tracking several operating metrics, including monthly active users (MAUs), daily active users (DAUs), paid subscribers, and subscription and total bookings. We believe each of these operating metrics provides useful information to investors and others. For information concerning these metrics as measured by us, see Part I, Item 2. “Management’s Discussion and Analysis of Financial Condition and Results of Operations - Key Operating Metrics and Non-GAAP Financial Measures.”
While these metrics are based on what we believe to be reasonable estimates of our user base for the applicable period of measurement, there are inherent challenges in measuring how our platform is used. These metrics are determined by using internal data gathered on an analytics platform that we developed and operate and have not been validated by an independent third party. This platform tracks user account and session activity. If we fail to maintain an effective analytics platform, our metrics calculations may be inaccurate.
We believe that these metrics are reasonable estimates of our user base for the applicable period of measurement, and that the methodologies we employ and update from time-to-time to create these metrics are reasonable bases to identify trends in user behavior. Because we update the methodologies we employ to create metrics, our operating metrics may not be comparable to those in prior periods. See the section titled “Risk Factors—Our user metrics and other estimates are subject to inherent challenges in measurement, and real or perceived inaccuracies in those metrics may negatively affect our reputation and our business”. Other companies, including companies in our industry, may calculate these metrics differently.
Risk Factors Summary
The following is a summary of the principal risks that could materially adversely affect our business, results of operations, and financial condition, all of which are more fully described in Part II, Item 1A. “Risk Factors.” This summary should be read in conjunction with Part II, Item 1A. “Risk Factors” and should not be relied upon as an exhaustive summary of the material risks facing our business.
If we fail to keep existing users or add new users, or if our users decrease their level of engagement with our products or do not convert to paying users, our revenue, financial results and business may be significantly harmed.
The online language learning industry is highly competitive, with low switching costs and a consistent stream of new products and entrants and innovation by our competitors may disrupt our business.
Changes to our existing brand and products, or the introduction of a new brand or products, could fail to attract or keep users or generate revenue and profits.
We have a limited operating history and, as a result, our past results may not be indicative of future operating performance.
Our costs are continuing to grow, and some of our investments have the effect of reducing our operating margin and profitability. If our investments are not successful, our business and financial performance could be harmed.
Our quarterly and annual operating results and other operating metrics may fluctuate from period to period, which makes these metrics difficult to predict.
Our operating metrics are subject to inherent challenges in measurement, and real or perceived inaccuracies in those metrics may negatively affect our reputation and our business.
4


We rely on third-party platforms such as the Apple App Store and the Google Play Store to distribute our products and collect payments. If we are unable to maintain a good relationship with such platform providers, if their terms and conditions or pricing changed to our detriment, if we violate, or if a platform provider believes that we have violated, the terms and conditions of its platform, or if any of these platforms loses market share or falls out of favor or is unavailable for a prolonged period of time, our business will suffer.
We rely on third-party hosting and cloud computing providers, like Amazon Web Services (“AWS”) and Google Cloud, to operate certain aspects of our business. A significant portion of our product traffic is hosted by a limited number of vendors, and any failure, disruption or significant interruption in our network or hosting and cloud services could adversely impact our operations and harm our business.
Our business is subject to complex and evolving US and international laws and regulations. Many of these laws and regulations are subject to change and uncertain interpretation, and could result in claims, changes to our business practices, monetary penalties, increased cost of operations, or declines in user growth or engagement, or otherwise harm our business.
Our success depends, in part, on our ability to access, collect, protect, and use personal data about our users and payers, and to comply with applicable data privacy laws.
The varying and rapidly-evolving regulatory framework on privacy and data protection across jurisdictions could result in claims, changes to our business practices, monetary penalties, increased cost of operations, brand damage, or declines in user growth or engagement, or otherwise harm our business.
Regulatory and legislative developments on the use of artificial intelligence and machine learning could adversely affect our use of such technologies in our products and services.
From time to time, we may be party to intellectual property-related litigation and proceedings that are expensive and time consuming to defend, and, if resolved adversely, could materially adversely impact our business, financial condition and results of operations.
We may fail to adequately obtain, protect and maintain our intellectual property rights or prevent third parties from making unauthorized use of such rights.
The dual class structure of our common stock has the effect of concentrating voting control with those stockholders who held our capital stock prior to the listing of our Class A common stock on the Nasdaq Global Select Market, including our directors, executive officers, and 5% stockholders and their respective affiliates, who held in the aggregate 82.5% of the voting power of our outstanding capital stock as of March 31, 2023. This ownership will limit or preclude your ability to influence corporate matters, including the election of directors, amendments of our organizational documents, and any merger, consolidation, sale of all or substantially all of our assets, or other major corporate transaction requiring stockholder approval.
5


Part I Financial Information
Item 1. Financial Statements (Unaudited)

DUOLINGO, INC. AND SUBSIDIARIES
UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS
(Amounts in thousands, except par value amounts)
March 31, 2023December 31, 2022
ASSETS
Current assets
Cash and cash equivalents$641,091 $608,180 
Accounts receivable52,509 46,728 
Deferred cost of revenues40,137 35,041 
Prepaid expenses and other current assets7,497 7,234 
Total current assets741,234 697,183 
Property and equipment, net12,842 12,969 
Goodwill4,050 4,050 
Intangible assets, net8,475 8,497 
Operating lease right-of-use assets21,779 22,508 
Deferred tax assets633 633 
Other assets1,366 1,507 
Total assets$790,379 $747,347 
LIABILITIES AND STOCKHOLDERS’ EQUITY
Current liabilities
Accounts payable$986 $1,177 
Deferred revenues181,942 157,550 
Income tax payable925 1,069 
Accrued expenses and other current liabilities18,960 21,970 
Total current liabilities202,813 181,766 
Long-term obligation under operating leases22,378 23,503 
Total liabilities225,191 205,269 
Commitments and contingencies (Note 8)
Stockholders’ equity
Class A common stock, $0.0001 par value; 2,000,000 shares authorized as of March 31, 2023 and December 31, 2022; 33,800 and 31,899 issued and outstanding at March 31, 2023 and December 31, 2022, respectively
Class B common stock, $0.0001 par value; 30,000 shares authorized as of March 31, 2023 and December 31, 2022; 7,218 and 8,462 issued and outstanding at March 31, 2023 and December 31, 2022, respectively
4 4 
Additional paid-in capital798,254 772,562 
Accumulated deficit(233,070)(230,488)
Total stockholders’ equity565,188 542,078 
Total liabilities and stockholders' equity$790,379 $747,347 
See accompanying notes to the Unaudited Condensed Consolidated Financial Statements.
6


DUOLINGO, INC. AND SUBSIDIARIES
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

(Amounts in thousands, except per share amounts)
Three Months Ended March 31,
20232022
Revenues$115,661 $81,220 
Cost of revenues31,492 21,490 
Gross profit84,169 59,730 
Operating expenses:
Research and development45,844 29,781 
Sales and marketing16,601 14,940 
General and administrative30,243 26,856 
Total operating expenses92,688 71,577 
Loss from operations(8,519)(11,847)
Other income (expense), net182 (312)
Loss before interest income and (benefit) provision for income taxes(8,337)(12,159)
Interest income5,639 33 
Loss before (benefit) provision for income taxes(2,698)(12,126)
(Benefit) provision for income taxes(116)28 
Net loss and comprehensive loss$(2,582)$(12,154)
Net loss per share attributable to Class A and Class B common stockholders, basic$(0.06)$(0.31)
Net loss per share attributable to Class A and Class B common stockholders, diluted$(0.06)$(0.31)
See accompanying notes to the Unaudited Condensed Consolidated Financial Statements.
7


DUOLINGO, INC. AND SUBSIDIARIES
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY

(Amounts in thousands)
Common Stock
SharesAmountAdditional Paid-In
Capital
Accumulated
Deficit
Total
BALANCE—January 1, 202238,272 $4 $683,966 $(170,914)$513,056 
Stock-based compensation— — 14,586 — 14,586 
Stock options exercised756 — 5,226 — 5,226 
Release of restricted stock units49 — — —  
Net loss— — — (12,154)(12,154)
BALANCE—March 31, 202239,077 $4 $703,778 $(183,068)$520,714 
BALANCE—January 1, 202340,361 $4 $772,562 $(230,488)$542,078 
Stock-based compensation— — 21,073 — 21,073 
Stock options exercised542 — 4,619 — 4,619 
Release of restricted stock units115 — — —  
Net loss— — — (2,582)(2,582)
BALANCE—March 31, 202341,018 $4 $798,254 $(233,070)$565,188 
See accompanying notes to the Unaudited Condensed Consolidated Financial Statements.

8


DUOLINGO, INC. AND SUBSIDIARIES
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(Amounts in thousands)
Three Months Ended March 31,
20232022
Cash flows from operating activities:
Net loss$(2,582)$(12,154)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization1,762 774 
Stock-based compensation21,073 14,586 
Gain on sale of capitalized software(100) 
Changes in assets and liabilities:
Deferred revenue24,392 20,834 
Accounts receivable(5,781)4,590 
Deferred cost of revenues(5,096)(3,561)
Prepaid expenses and other current assets(263)66 
Accounts payable(345)(5,800)
Accrued expenses and other current liabilities(3,201)1,265 
Noncurrent assets and liabilities(255)27 
Net cash provided by operating activities29,604 20,627 
Cash flows from investing activities:
Capitalized software expense and purchases of intangible assets(731)(1,117)
Purchase of property and equipment(681)(1,327)
Proceeds from sale of capitalized software100  
Net cash used for investing activities(1,312)(2,444)
Cash flows from financing activities:
Proceeds from exercise of stock options4,619 5,226 
Net cash provided by financing activities4,619 5,226 
Net increase in cash and cash equivalents32,911 23,409 
Cash and cash equivalents - Beginning of period608,180 553,922 
Cash and cash equivalents - End of period$641,091 $577,331 
See accompanying notes to the Unaudited Condensed Consolidated Financial Statements.
9


DUOLINGO, INC. AND SUBSIDIARIES
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION

(Amounts in thousands)
Three Months Ended March 31,
20232022
Supplemental disclosure of cash flow information:
Cash paid for interest$ $ 
Cash paid for income taxes$28 $3 
Supplemental disclosure of noncash operating activities:
Implementation costs for cloud computing included in Current liabilities$ $153 
Supplemental disclosure of noncash investing activities:
Capitalized software and purchases of intangible assets included in Current liabilities$ $14 
Property and equipment included in Current liabilities$201 $178 
Landlord incentive included in Prepaid expenses and other current assets$ $1,102 
See accompanying notes to the Unaudited Condensed Consolidated Financial Statements.
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DUOLINGO, INC. AND SUBSIDIARIES
NOTES TO THE UNAUDITED CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
1.     DESCRIPTION OF THE BUSINESS AND BASIS OF PRESENTATION
Duolingo, Inc. (the “Company” or “Duolingo”) was formed on August 18, 2011, and the Duolingo app was launched to the general public on June 19, 2012. The Company’s headquarters are located in Pittsburgh, Pennsylvania.
Duolingo is a US-based mobile learning platform, as well as a digital language proficiency assessment exam. The Company has a freemium business model: the app and the website are accessible free of charge, although Duolingo also offers premium services for a subscription fee. As of the date of this filing, Duolingo offers courses in over 40 different languages, including Spanish, English, French, German, Italian, Portuguese, Japanese and Chinese. We have locations in the United States, China and Germany.
Principles of Consolidation—The Unaudited Condensed Consolidated Financial Statements include the accounts of the Company and subsidiaries over which the Company has control. All intercompany transactions and balances have been eliminated.
Basis of Presentation—The accompanying Unaudited Condensed Consolidated Financial Statements have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) from the Company’s accounting records and reflect the consolidated financial position and results of operations for the three months ended March 31, 2023 and 2022. Unless otherwise specified, all dollar amounts are referred to in thousands.
The Unaudited Condensed Consolidated Financial Statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such SEC rules. We believe that the disclosures made are adequate to make the information presented not misleading. In our opinion, all adjustments considered necessary for a fair presentation of the financial statements have been included, and all adjustments are of a normal and recurring nature. We consistently applied the accounting policies consistent with the annual Unaudited Condensed Consolidated Financial Statements elsewhere in this Quarterly Report on Form 10-Q, in preparing these Unaudited Condensed Consolidated Financial Statements. These Unaudited Condensed Consolidated Financial Statements should be read in conjunction with the audited financial statements and the notes for the fiscal year ended December 31, 2022 included in the Annual Report on Form 10-K and filed with the SEC.
2.     SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Accounting Principles—The Unaudited Condensed Consolidated Financial Statements and accompanying notes are prepared in accordance with GAAP.
Use of Estimates—The preparation of Unaudited Condensed Consolidated Financial Statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the Unaudited Condensed Consolidated Financial Statements and accompanying notes. Significant estimates and assumptions reflected in the Unaudited Condensed Consolidated Financial Statements include, but are not limited to, useful lives of property and equipment, valuation of deferred tax assets and liabilities, stock-based compensation, common stock valuation, operating lease right-of-use assets and liabilities, capitalization of internally developed software and associated useful lives and contingent liabilities. Actual results may differ materially from such estimates. Management believes that the estimates, and judgments upon which they rely, are reasonable based upon information available to
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them at the time that these estimates and judgments are made. To the extent that there are material differences between these estimates and actual results, the Company’s Unaudited Condensed Consolidated Financial Statements will be affected.
Cash and Cash Equivalents—Cash consists primarily of cash on hand and bank deposits. Cash equivalents consist primarily of money market accounts with maturities of three months or less at the date of acquisition and are stated at cost, which approximates fair value. The Company maintains cash deposits with financial institutions that may exceed federally insured limits at times. The following table shows the breakout between cash and money market funds.
March 31,
2023
December 31,
2022
Cash$48,462 $91,189 
Money market funds592,629 516,991 
Total$641,091 $608,180 
The Money market funds are considered Level 1 financial assets. Level 1 financial assets use inputs that are the unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date.
Advertising Costs Advertising costs were approximately $11,093 and $10,954 for the three months ended March 31, 2023 and 2022, respectively, and are included within Sales and marketing in the Unaudited Condensed Consolidated Statements of Operations and Comprehensive Loss.
Income Taxes—The Company’s provision for income taxes is computed by using an estimate of the annual effective tax rate, adjusted for discrete items taken into account in the relevant period, if any. Each quarter, the annual effective income tax rate is recomputed and if there are material changes in the estimate, a cumulative adjustment is made.
Concentration of Credit Risk—The Company’s concentration of credit risk relates to financial institutions holding the Company’s cash and cash equivalents and platforms with significant accounts receivable balances and revenue transactions.
The Company maintains cash deposits with financial institutions that may exceed federally insured limits at times. Management believes that the financial institutions that hold the Company’s deposits are financially credit worthy and, accordingly, minimal credit risk exists with respect to those balances.
The majority of our revenue comes through our subscriptions and advertising streams and payments are made to Duolingo through service providers. The top three service providers, Apple, Google and Stripe accounted for 66.9%, 19.3% and 10.0% of total Accounts receivable as of March 31, 2023, respectively. The top two service providers, Apple and Google, accounted for 56.2% and 27.5% of total Accounts receivable as of December 31, 2022, respectively.
Three service providers, Apple, Google and Stripe processed 57.1%, 26.2% and 11.9% of total Revenues for the three months ended March 31, 2023, respectively. Two services providers, Apple and Google, processed 51.1% and 29.1% of total Revenues for the three months ended March 31, 2022, respectively.
Impairment of long-lived assets— The Company reviews its long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If the sum of the estimated undiscounted future cash flows expected to result from the use and eventual disposition of an asset is less than the carrying amount of the asset, an impairment loss is recognized. Measurement of an impairment loss is based on the fair value of the asset. No assets were impaired during the three months ended March 31, 2023 and 2022.
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Recently Issued Pronouncements Not Yet Adopted
There are no recently issued accounting pronouncements that the Company has not yet adopted that they believe are applicable or would have a material impact on the financial statements of the Company.
Recently Adopted Accounting Pronouncements
There are no recently adopted accounting pronouncements.
3.      REVENUE
The Company has three predominant sources of revenues; time-based subscriptions, in-app advertising placement by third parties, and the Duolingo English Test. Revenue is recognized upon transfer of control of promised products or services to users in an amount that reflects the consideration the Company expects to receive in exchange for those services. The Company does not enter into contracts with a customer that contain multiple promises that result in multiple performance obligations. Revenue is recorded net of taxes assessed by a government authority that are both imposed on and concurrent with specific revenue transactions between us and our users.
Revenue from time-based subscriptions includes a stand-ready obligation to provide hosting services that are consumed by the customer over the subscription period. Users can purchase Duolingo monthly or they can purchase a six-month or year-long subscription and pay for the subscription at the time of purchase. Under the year-long subscription, users can also purchase a single plan or a family plan. The family plan includes up to six users on one subscription. Such payments are initially recorded to deferred revenue. The user has the ability to download limited content offline. However, as there is a significant level of integration and interdependency with the online functionality, the Company considers the service to be a single performance obligation for the online and offline content.
The Company enters into arrangements with advertising networks to monetize the in-app advertising inventory. Revenue from in-app advertising placement is recognized at a point in time when the advertisement is placed and is based upon the amount received.
Duolingo English Test revenue is generally recognized once the tests have gone through the proctoring process and a certification decision has been made. This process usually takes less than 48 hours after the test has been completed and uploaded. Customers have 21 days from the date of purchase to take the exam or their purchase will expire and revenue will be recognized. Virtually all customers complete their exams prior to expiration. Sometimes organizations may purchase tests in bulk via coupons with a one year expiration date. The Company will defer revenue from all tests that have neither been proctored nor expired.
The Company’s users have the option to purchase consumable in-app virtual goods. The Company recognizes revenue over the period in which the user consumes the virtual good, which is generally within a month.
The Company also recognizes revenue from Duo’s Taquería, a restaurant that opened during 2022, in the space adjacent to our headquarters in Pittsburgh. Revenue from Duo’s Taquería is recognized at a point in time when the sales are made.
Principal Agent Considerations—The Company makes its application available to be downloaded through third-party digital distribution service providers. Users who purchase subscriptions also pay through the respective app stores. The Company evaluates the purchases via third-party payment processors to determine whether its revenues should be reported gross or net of fees retained by the payment processor. The Company is the principal in the transaction with the end user as a result of
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controlling, hosting, and integrating the delivery of the virtual items to the end user. The Company records revenue gross as a principal and records fees paid to third-party payment processors as Cost of revenues.
Contract Balances—Deferred revenue mostly consists of payments we receive in advance of revenue recognition, and is mostly related to time-based subscriptions, which will be recognized into revenue over the course of the upcoming year (recognized over 12 months or less). Additionally, the Duolingo English Test has deferred revenue related to tests that have been purchased, but will not be recognized until the tests have been proctored.
Disaggregation of Revenue
In accordance with ASC 606, Revenue from Contracts with Customers, the Company disaggregates revenue from contracts with customers into revenue stream, which most closely depicts how the nature, amount, timing and uncertainty of revenue and cash flows are affected by economic factors.
Three Months Ended March 31,
20232022
Revenues:
Subscription$86,185 $58,010 
Advertising11,635 11,748 
Duolingo English Test9,972 8,080 
Other (1)7,869 3,382 
Total revenues$115,661 $81,220 
________________
(1) Other revenue is mainly comprised of in-app purchases of virtual goods.
Changes in deferred revenues were as follows:
Three Months Ended March 31,
20232022
Beginning balance—January 1$157,550 $98,267 
Amount from beginning balance recognized into revenue(65,492)(40,474)
Recognition of deferred revenue(30,129)(22,195)
Deferral of revenue120,013 83,503 
Ending balance—March 31$181,942 $119,101 
4.    PROPERTY and EQUIPMENT, net
Property and equipment consists of the following as of March 31, 2023 and December 31, 2022:
20232022
Leasehold improvements$16,693 $15,983 
Furniture, fixtures and equipment5,376 5,204 
Total property and equipment22,069 21,187 
Less: accumulated depreciation(9,227)(8,218)
Total property and equipment, net$12,842 $12,969 
Depreciation expense is included within the following financial statement line items within the Company’s Unaudited Condensed Consolidated Statements of Operations and Comprehensive Loss.
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Three Months Ended March 31,
(In thousands)20232022
Research and development$407 $134 
Sales and marketing48 19 
General and administrative554 412 
Total$1,009 $565 

5.    INTANGIBLE ASSETS AND GOODWILL
Intangible assets consist mostly of capitalized software, with $18 of other intangible assets as of March 31, 2023 and December 31, 2022.
20232022
Intangible assets$17,250 $16,827 
Less: accumulated amortization(8,775)(8,330)
Intangible assets, net$8,475 $8,497 
The Company capitalized $731 and $1,131 of software development costs during the three months ended March 31, 2023 and 2022, respectively. Amortization expense is included within the following financial statement line items within the Company’s Unaudited Condensed Consolidated Statements of Operations and Comprehensive Loss
Three Months Ended March 31,
(In thousands)20232022
Cost of revenues$403 $ 
Sales and marketing
350 209 
Total
$753 $209 

Goodwill was $4,050 at March 31, 2023 and December 31, 2022. As of March 31, 2023 and December 31, 2022, $3,915 and $3,983 of goodwill is deductible for tax purposes, respectively.
6.    INCOME TAXES
Year-to-date income tax expense or benefit is the product of the most current projected annual effective tax rate (“PAETR”) and the actual year-to-date pretax income (loss) adjusted for any discrete items. The income tax expense or benefit for a particular quarter, is the difference between the year-to-date calculation of income tax expense or benefit and the year-to-date calculation for the prior quarter. Items unrelated to current period ordinary income or (loss) are recognized entirely in the period identified as a discrete item of tax.
The Company’s PAETR was lower than the US federal statutory rate of 21.0% during the three months ended March 31, 2023 and 2022 primarily due to the impact of maintaining a US valuation allowance provided on US deferred tax assets.
The Company continues to maintain a full valuation allowance on US federal and state net deferred tax assets for the period ending March 31, 2023 as a result of pre-tax losses incurred since the Company’s inception in early 2012. The Company is projecting pre-tax loss in 2023.
Current and Prior Period Tax Expense
The Company’s income before taxes, income tax provision or benefit and effective tax rates were as follows:
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Three Months Ended March 31,
(In thousands, except percentages)20232022
Loss before (benefit) provision for income taxes$(2,698)$(12,126)
(Benefit) provision for income taxes(116)28 
Effective tax rate4.3 %(0.2)%
The change in the effective tax rate from the prior year was primarily due to increased tax benefits related to stock-based compensation.
The tax benefit recorded for the current period is primarily attributable to the excess tax benefits of stock-based compensation, which have been recognized discretely. This benefit was partially offset by non-deductible compensation.
7.    STOCK-BASED COMPENSATION
Prior to the IPO, the Company granted options to purchase shares of the Company’s common stock and restricted stock units (“RSU”) in respect of shares of the Company’s common stock to employees, directors and consultants under the Company’s 2011 Equity Incentive Plan. In July 2021, Duolingo adopted the 2021 Incentive Award Plan (“2021 Plan”) and the 2021 Employee Stock Purchase Plan (“ESPP”), each of which became effective on July 26, 2021 in connection with the IPO. An aggregate of 7,946 shares and 1,119 shares of Class A common stock were made available for future issuance under the 2021 Plan and ESPP, respectively. On each January 1, the number of shares of the Company’s Class A common stock available for issuance under the 2021 Plan have been, and through January 1, 2031, will be, increased by the lesser of (i) 5% of the shares outstanding on the preceding December 31 (calculated on an as-converted basis) and (B) such smaller number of shares of common stock as determined by the Board or the Committee (as defined in the 2021 Plan). On January 1, 2023, the 2021 Plan and ESPP were increased by 2,018 shares and 319 shares, respectively.
The Company’s stock options vest based on terms in the stock option agreements, which generally provide for vesting over four years based on continued service to the Company and its subsidiaries. Each option has a term of ten years. Stock options granted under the 2021 Plan must generally have an exercise price of not less than the estimated fair market value of the underlying Class A common stock at the date of the grant. No options have been granted under the 2021 Plan.
A summary of stock option activity under the Plans was as follows:
Number of
options
Weighted-
average
exercise
price
Weighted- average remaining contractual life (years)Aggregate intrinsic value
Options outstanding at January 1, 20234,410 $14.04 6.25$251,832 
Granted (1) 
Exercised(542)8.57 
Forfeited and expired(3)22.37 
Options outstanding at March 31, 2023
3,865 $14.80 6.17$493,610 
Options exercisable at March 31, 20233,297 $14.05 6.00$423,829 
________________
(1) There were no stock options granted during the three months ended March 31, 2023 and 2022.


The total intrinsic value of options exercised was approximately $55,062 and $60,334 for the periods ended March 31, 2023 and 2022, respectively. 
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A summary of RSU activity under the Plans was as follows:
Restricted stock unitsWeighted-
average
grant date fair value per share
Outstanding at January 1, 2023
2,036 $85.74 
Granted185 97.62 
Released(115)84.18 
Forfeited(58)97.80 
Outstanding at March 31, 2023
2,048 $86.56 
As of March 31, 2023, there was approximately $4,522 of unrecognized compensation cost related to stock options granted under the plans with a weighted-average period of approximately one year. The amount of unrecognized compensation expense for RSUs as of March 31, 2023 was $163,373 with a weighted-average period of approximately three years, for a total unrecognized compensation expense of $167,895.
There were 10,011 shares available for grant at March 31, 2023.
Performance-based RSUs
In June 2021, the Company granted an aggregate of 1,800 performance-based RSUs (the “Founder Awards”) to the Company’s founders. The Founder Awards vest upon the satisfaction of both a service-based condition and a performance-based condition and generally are settled one year after vesting. The service-based condition is satisfied as to 25% of the Founder Awards on each anniversary of the completion of the IPO, subject to the continuous service of the founders through the applicable date. The performance-based condition will be satisfied with respect to each of 10 equal tranches only if the trailing 60-calendar day volume-weighted-average closing trading price of the Company’s Class A common stock reaches certain stock-price hurdles for each such tranche, as set forth below, over a period of 10 years from the date of grant.
Any RSUs associated with stock-prices hurdle not achieved by the tenth anniversary of the date of grant will terminate and be canceled for no additional consideration to the founders. The stock-price hurdles and number of RSUs eligible to vest will be adjusted to reflect any stock splits, stock dividends, combinations, reorganizations, reclassifications, or similar events under the 2021 Plan. The Founder Awards will be settled in shares of the Company’s Class B common stock.
TrancheCompany Stock Price HurdleNumber of RSUs Eligible to Vest
1$127.50 90 
2$153.00 90 
3$178.50 90 
4$204.00 180 
5$255.00 180 
6$306.00 180 
7$357.00 180 
8$408.00 180 
9$612.00 270 
10$816.00 360 
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The Company estimated the grant date fair value of the Founder Awards using a model based on multiple stock-price paths developed through the use of a Monte Carlo simulation that incorporates into the valuation the possibility that the stock-price hurdles may not be satisfied. The weighted-average grant date fair value of the Founder Awards was estimated to be $61.56 per share and the Company estimates that it will recognize total stock-based compensation expense of approximately $110,817 over the derived service period of each of the ten separate tranches which is between 3.585.92 years. If the stock-price hurdles are met sooner than the requisite service period, the stock-based compensation expense will be adjusted to prospectively recognize the remaining expense over the remaining derived service period. Provided that the founders continue to provide services to the Company, stock-based compensation expense is recognized over the derived service period, regardless of whether the stock-price hurdles are achieved. The stock-price hurdles for the first two tranches were met during 2021. No additional stock-price hurdles have been met since. The Company recognized $7,140 and $8,019 of stock-based compensation expense related to these awards for the three months ended March 31, 2023 and 2022, respectively, which is included within General and administrative in the Unaudited Condensed Consolidated Statements of Operations and Comprehensive Loss. As of March 31, 2023, there is $56,217 of unrecognized compensation expense related to these awards.
Total stock-based compensation expense was $21,073 and $14,586 for the three months ended March 31, 2023 and 2022, respectively.
Stock based compensation expense is included in the Unaudited Condensed Consolidated Statements of Operations and Comprehensive Loss as shown in the following table:
Three Months Ended March 31,
20232022
Cost of revenues$11 $6 
Research and development9,346 3,632 
Sales and marketing779 348 
General and administrative10,937 10,600 
Total$21,073 $14,586 
Nominal amounts of stock based compensation expense is capitalized into intangible assets for the three months ended March 31, 2023 and 2022.
8.    COMMITMENTS AND CONTINGENCIES
Legal Proceedings— From time to time, the Company may become involved in various legal proceedings in the ordinary course of its business and may be subject to third-party infringement claims. The outcome of any such claims or proceedings, regardless of the merits, is inherently uncertain. The Company is not currently party to any material legal proceedings.
Related Parties— The Company has determined that there were no transactions with related parties as of or during the three months ended March 31, 2023 and 2022.
9.    ACCRUED EXPENSES AND OTHER CURRENT LIABILITIES
Accrued expenses and other current liabilities consisted of the following:
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March 31,
2023
December 31, 2022
Obligations under current leases$5,524 $4,903 
Marketing related accruals2,726 3,464 
Sales and VAT tax accrual2,421 2,396 
Employee-related costs1,938 4,233 
Other6,351 6,974 
Total$18,960 $21,970 
10.    EMPLOYEE BENEFIT PLAN
The Company sponsors a profit sharing plan with a 401(k) feature, the Duolingo Retirement Plan, (the “Plan”) for eligible employees. The current Plan, effective January 1, 2021, provides for Company safe harbor matching contributions of 100% of the first 4% of the employees’ elective deferrals and 50% of the next 2%, with vesting starting upon the first day of employment. The Company also has the option to make discretionary matching or profit sharing contributions. The Company made safe harbor matching contributions of approximately $1,397 and $983 for the three months ended March 31, 2023 and 2022, respectively. The Company did not make any discretionary matching or profit sharing contributions during the three months ended March 31, 2023 and 2022.
11.    LOSS PER SHARE
Basic and diluted net loss per share attributable to common stockholders is presented in conformity with the two-class method required for participating securities.
Basic net loss per share attributable to common stockholders is calculated by dividing the net loss by the weighted-average number of shares of common stock outstanding during the period, less shares subject to repurchase. The diluted net loss per share attributable to common stockholders is calculated by giving effect to all potential dilutive common stock equivalents outstanding for the period.
Three Months Ended March 31,
(In thousands, except per share data)20232022
Numerator:
Net loss attributable to Class A and Class B common stockholders$(2,582)$(12,154)
Denominator:
Weighted-average shares in computing net loss per share attributable to Class A and Class B common stockholders, basic and diluted40,618 38,590 
Basic loss per common share$(0.06)$(0.31)
Diluted loss per common share$(0.06)$(0.31)
The rights, including the liquidation and dividend rights, of the holders of Class A and Class B common stock are identical, except with respect to voting and conversion. Each share of Class A common stock is entitled to one vote per share and each share of Class B common stock is entitled to 20 votes per share. Each share of Class B common stock is convertible into a share of Class A common stock voluntarily at any time by the holder, and automatically upon certain events. The Class A common stock has no conversion rights. As the liquidation and dividend rights are identical for Class A and Class B common stock, the undistributed earnings are allocated on a proportional basis and the resulting net loss per share attributable to common stockholders will, therefore, be the same for both Class A and Class B common stock on an individual or combined basis.
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Since the Company was in a net loss position for the three months ended March 31, 2023 and 2022, there is no difference between the number of shares used to calculate basic and diluted loss per share. The potential shares of common stock that were excluded from the computation of diluted net loss per share attributable to common stockholders for the period presented because including them would have been antidilutive are as follows:
Three Months Ended March 31,
(in thousands)20232022
Founder awards where performance has been met180 180 
Stock options outstanding (1)3,865 5,435 
RSUs outstanding (1)2,048 756 
Total6,093 6,371 
________________
(1) Prior year amounts were adjusted in the current year table to include unvested options and RSUs.

Founder awards of 1,620, where the performance criteria has not been satisfied, are excluded from the above table because the stock-price hurdles for those awards had not been met as of March 31, 2023 and 2022.

12.    SUBSEQUENT EVENTS
None.
Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations
The following discussion and analysis of our financial condition and results of operations should be read in conjunction with our Unaudited Condensed Consolidated Financial Statements and related notes included elsewhere in this Quarterly Report on Form 10-Q, the audited consolidated financial statements and related notes included in our Annual Report on Form 10-K and in Part II, Item 7. “Management’s Discussion and Analysis of Financial Condition and Results of Operations” of our Annual Report on Form 10-K. The following discussion contains forward-looking statements, such as those relating to our plans, objectives, expectations, intentions, and beliefs, that involve risks, uncertainties and assumptions. Our actual results could differ materially from these forward-looking statements as a result of many factors, including those discussed in Part II, Item 1A. “Risk Factors,” “Special Note Regarding Forward-Looking Statements,” included elsewhere in this Quarterly Report on Form 10-Q, and in in Part II, Item 7. “Management’s Discussion and Analysis of Financial Condition and Results of Operations” of our Annual Report on Form 10-K. Our historical results are not necessarily indicative of the results that may be expected for any periods in the future.
Amounts reported in millions are rounded based on the amounts in thousands. As a result, the sum of the components reported in millions may not equal the total amount reported in millions due to rounding. In addition, percentages presented are calculated from the underlying numbers in thousands and may not add to their respective totals due to rounding.
Overview
Our flagship app has organically become the world’s most popular way to learn languages and the top-grossing Education app in the App Stores, offering courses in over 40 languages to over 70 million monthly active users for the three months ended March 31, 2023. We believe that we have become the preeminent online destination for language learning due to our beautifully designed products, exceptional user engagement, and demonstrated learning efficacy.
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Key Operating Metrics and Non-GAAP Financial Measures
We regularly review a number of key operating metrics and non-GAAP financial measures to evaluate our business, measure our performance, identify trends, prepare financial projections and make business decisions. The measures set forth below should be considered in addition to, not as a substitute for or in isolation from, our financial results prepared in accordance with GAAP. Monthly active users (MAUs) and daily active users (DAUs), along with paid subscribers, are operating metrics that help inform management about the underlying growth in users of our platform, and are a measure of our monetization efforts. To calculate the year-over-year change in MAUs and DAUs for a given period, we subtract the average for the same period in the previous year from the average for the same period in the current year and divide the result by the average for the same period in the previous year. Other companies, including companies in our industry, may calculate these measures differently or not at all, which reduces their usefulness as comparative measures.
Three Months Ended March 31,
(Operating metrics are in millions)20232022
Operating Metrics
Monthly active users (MAUs)72.6 49.2 
Daily active users (DAUs)20.3 12.5 
Paid subscribers (at period end)4.8 2.9 
Three Months Ended March 31,
20232022
Operating Metrics
Subscription bookings$110,122 $78,539 
Total bookings$140,054 $102,054 
Non-GAAP Financial Measures
Net loss (GAAP)$(2,582)$(12,154)
Adjusted EBITDA$15,111 $3,946 
Net cash provided by operating activities (GAAP)$29,604 $20,627 
Free cash flow$28,792 $18,928 
Operating Metrics
Monthly active users (MAUs). MAUs are defined as unique Duolingo users who engage with our mobile language learning application or the language learning section of our website each month. MAUs are reported for a measurement period by taking the average of the MAUs for each calendar month in that measurement period. The measurement period for MAUs is the three months ended March 31, 2023 and the same period in the prior year where applicable, and the analysis of results is based on those periods. MAUs are a measure of the size of our global active user community on Duolingo.
We had approximately 72.6 million and 49.2 million MAUs for the three months ended March 31, 2023 and 2022, respectively, representing an increase of 47% from the prior year period. We grew MAUs through product initiatives designed to make the app more social and engaging, through marketing, and
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through improving our courses, all of which we believe helped us attract new users, retain existing users, and reengage the millions of former users who return to our language learning app.
Daily active users (DAUs). DAUs are defined as unique Duolingo users who engage with our mobile language learning application or the language learning section of our website each calendar day. DAUs are reported for a measurement period by taking the average of the DAUs for each day in that measurement period. The measurement period for DAUs is the three months ended March 31, 2023 and the same period in the prior year where applicable, and the analysis of results is based on those periods. DAUs are a measure of the consistent engagement of our global user community on Duolingo.
We had approximately 20.3 million and 12.5 million DAUs for the three months ended March 31, 2023 and 2022, respectively, representing an increase of 62% from the prior year period. The DAU / MAU ratio, which we believe is an indicator of user engagement, increased to 28.0% from 25.4% a year ago. We grew DAUs through many of the same product initiatives as we grew MAUs, such as making the product more fun and engaging.
Paid Subscribers. Paid subscribers are defined as users who pay for access to any Duolingo subscription offering and had an active subscription as of the end of the measurement period. Each unique user account is treated as a single paid subscriber regardless of whether such user purchases multiple subscriptions, and the count of paid subscribers does not include users who are currently on a free trial or who are non-paying members of a family plan.
As of March 31, 2023 and 2022, we had approximately 4.8 million and 2.9 million paid subscribers, respectively, representing an increase of 63% from the prior year period. We grew paid subscribers through product improvements that led to higher subscriber conversion and steady subscriber retention.
Subscription Bookings and Total Bookings. Subscription bookings represent the amounts we receive from a purchase of any Duolingo subscription offering. Total bookings represent the amounts we receive from a purchase of any Duolingo subscription offering, a purchase of a Duolingo English Test, an in-app purchase of a virtual good, and from advertising networks for advertisements served to our users. We believe bookings provide an indication of trends in our operating results, including cash flows, that are not necessarily reflected in our revenues because we recognize subscription revenues ratably over the lifetime of a subscription, which is generally from one to twelve months.
For the three months ended March 31, 2023 and 2022, we generated $110.1 million and $78.5 million of subscription bookings, respectively, representing an increase of 40% from the prior year period. We grew subscription bookings by selling more first-time and renewal subscriptions.
For the three months ended March 31, 2023 and 2022, we generated $140.1 million and $102.1 million of total bookings, respectively, representing an increase of 37% from the prior year period. We grew total bookings through the growth in subscription bookings noted above, in addition to growth in the Duolingo English Test and other bookings, primarily related to in-app purchases.
Non-GAAP Financial Measures
We use certain non-GAAP financial measures to supplement our Unaudited Condensed Consolidated Financial Statements, which are presented in accordance with GAAP. These non-GAAP financial measures include Adjusted EBITDA and free cash flow. We use these non-GAAP financial measures for financial and operational decision-making and as a means to evaluate period-to-period comparisons. By excluding certain items that may not be indicative of our recurring core operating results, we believe that Adjusted EBITDA and free cash flow provide meaningful supplemental information regarding our performance. Accordingly, we believe these non-GAAP financial measures are useful to investors and others because they allow for additional information with respect to financial measures used by management in its financial and operational decision-making and they may be used by our institutional
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investors and the analyst community to help them analyze the health of our business. However, there are a number of limitations related to the use of non-GAAP financial measures, and these non-GAAP measures should be considered in addition to, not as a substitute for or in isolation from, our financial results prepared in accordance with GAAP. Other companies, including companies in our industry, may calculate these non-GAAP financial measures differently or not at all, which reduces their usefulness as comparative measures.
The Company also uses non-GAAP constant currency revenues and non-GAAP percentage change in constant currency revenues, which exclude the impact of fluctuations in foreign currency exchange rates, for financial and operational decision-making and as a means to evaluate period-to-period comparisons. The effect of currency exchange rates on our business is an important factor in understanding period to period comparisons and we believe this information is useful to investors to facilitate comparisons and better identify trends in our business. The impact of changes in foreign currency may vary significantly from period to period, and such changes generally are outside of the control of our management. We calculate constant currency revenues by using current period foreign currency revenues and translating them to constant currency using prior year comparable period exchange rates. Constant currency revenue percentage change is calculated by determining the change in current period revenues over prior year comparable period revenues where current period foreign currency revenues are translated using prior year comparable period exchange rates.
Adjusted EBITDA. Adjusted EBITDA is defined as net loss excluding interest income, income tax provision, depreciation and amortization, stock-based compensation expenses related to equity awards, IPO and public company costs, acquisition earn-out costs and gain on sale of capitalized software. Adjusted EBITDA is used by management to evaluate the financial performance of our business and we present Adjusted EBITDA because we believe it is helpful in highlighting trends in our operating results and that it is frequently used by analysts, investors and other interested parties to evaluate companies in our industry. The following table presents a reconciliation of our net loss, the most directly comparable financial measure presented in accordance with GAAP, to Adjusted EBITDA.
Three Months Ended March 31,
(In thousands)
20232022
Net loss$(2,582)$(12,154)
Interest income(5,639)(33)
(Benefit) provision for income taxes(116)28 
Depreciation and amortization1,762 774 
Stock-based compensation expenses related to equity awards (1)21,673 15,100 
IPO and public company costs (2)
— 231 
Acquisition earn-out costs (3)113 — 
Gain on sale of capitalized software (4)(100)— 
Adjusted EBITDA$15,111 $3,946 
________________
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(1)In addition to stock-based compensation expense of $21.1 million and $14.6 million for the three months ended March 31, 2023 and 2022, respectively, this includes costs incurred related to taxes paid on equity transactions as follows:
Three Months Ended March 31,
(In thousands)20232022
Research and development
$240 $226 
Sales and marketing
14 15 
General and administrative
346 273 
Total
$600 $514 

(2)IPO and public company costs include costs associated with the establishment of our public company structure and processes, including consultant costs, a one-time fee associated with the set-up of our initial proxy statement, and fees paid to consultants and Deloitte for work in connection with remediation of the material weakness disclosed in our Annual Report on Form 10-K. These costs are included in General and administration expense within our Unaudited Condensed Consolidated Statements of Operations and Comprehensive Loss.

(3)Represent costs incurred related to the earn-out payment on an acquisition, which is included within General and administrative within our Unaudited Condensed Consolidated Statements of Operations and Comprehensive Loss.

(4)Represents proceeds from a sale of capitalized software, which is included within Other income (expense), net within our Unaudited Condensed Consolidated Statements of Operations and Comprehensive Loss.


For the three months ended March 31, 2023 and 2022, we generated a net loss of $2.6 and $12.2, respectively. Net loss decreased due to a combination of our growth in revenue and reduction in operating expenses as a percentage of revenue as compared to the prior year periods.
For the three months ended March 31, 2023 and 2022, we generated Adjusted EBITDA of $15.1 million and $3.9 million, respectively. Adjusted EBITDA increased due to the same reasons as net loss discussed above.
Free Cash Flow: Free cash flow represents net cash provided by operating activities, reduced by capitalized software development costs and purchases of property and equipment and increased by IPO and public company costs and taxes paid related to stock-based compensation equity awards, as we believe they are not indicative of future liquidity. We believe that free cash flow is a measure of liquidity that provides useful information to our management, investors, and others in understanding and evaluating the strength of our liquidity and future ability to generate cash that can be used for strategic opportunities or investing in our business. Free cash flow has certain limitations in that it does not represent our residual cash flow for discretionary expenditures and our non-discretionary commitments. The following table presents a reconciliation of net cash provided by operating activities, the most directly comparable financial measure calculated in accordance with GAAP, to free cash flow:
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Three Months Ended March 31,
(In thousands)
20232022
Net cash provided by operating activities$29,604 $20,627 
Less: Capitalized software development costs and purchases of intangible assets(731)(1,117)
Less: Purchases of property and equipment(681)(1,327)
Plus: IPO and public company costs (1)
— 231 
Plus: Taxes paid related to stock-based compensation equity awards (2)600 514 
Free cash flow$28,792 $18,928 
________________
(1)IPO and public company costs include costs associated with the establishment of our public company structure and processes, including consultant costs, a one-time fee associated with the set-up of our initial proxy statement, and fees paid to consultants and Deloitte for work in connection with remediation of the material weakness disclosed in our Annual Report on Form 10-K for the fiscal year ended December 31, 2022.
(2)Includes taxes paid on equity transactions.

For the three months ended March 31, 2023 and 2022, we generated $29.6 million and $20.6 million of net cash provided by operating activities, respectively. The increase in net cash provided by operating activities was was mainly due to the decrease in net loss in addition to an increase in stock-based compensation expense.
For the three months ended March 31, 2023 and 2022, we generated $28.8 million and $18.9 million of free cash flow, respectively. The increase in free cash flow was mainly attributable to the increase in net cash provided by operating activities and slight decreases in capitalized software and purchases of property and equipment.
Constant Currency: The effect of currency exchange rates on our business is an important factor in understanding period to period comparisons. We use non-GAAP constant currency revenues and non-GAAP percentage change in constant currency revenues for financial and operational decision-making and as a means to evaluate period-to-period comparisons.
Total revenues were $115.7 million for the three months ended March 31, 2023, an increase of 42% over the three months ended March 31, 2022 on a reported basis, and 47% on a constant currency basis. Subscription revenues totaled $86.2 million for the three months ended March 31, 2023, an increase of 49% over the three months ended March 31, 2022 on a reported basis, and 53% on a constant currency basis.
Results of Operations
Comparison for the three months ended March 31, 2023 and 2022
Revenue
We generate revenues primarily from the sale of subscriptions. The term-length of our subscription agreements are primarily monthly or annual. We began to roll out a family plan during the second half of 2021 and as of March 31, 2023 offer it exclusively as an annual subscription. We have historically had a six-month subscription plan, but during the fourth quarter of 2020, we began to phase it out. We also generate revenue from advertising, the in-app sale of virtual goods, and the Duolingo English Test.
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Cost of Revenues
Cost of revenues predominantly consists of third-party payment processing fees charged by various distribution channels, and also includes hosting fees. To a much lesser extent, cost of revenues includes costs for contractors, wages and stock-based compensation for certain employees in the capacity of customer support, amortization of revenue generating capitalized software, and depreciation of certain property and equipment.
We intend to continue to invest additional resources in our infrastructure and our customer support and success organization to expand the capabilities of our platform and ensure that our users are realizing the full benefit of our products. The level, timing, and relative investment in these areas could affect our cost of revenues in the future.
Gross Profit and Gross Margin
Gross profit represents revenues less cost of revenues. Gross margin is gross profit expressed as a percentage of revenues. Our gross profit may fluctuate from period to period as our revenues fluctuate, and also as a result of the timing and amount of investments we make in items related to cost of revenues.
Operating Expenses
Our operating expenses consist of research and development, sales and marketing, and general and administrative expenses. Personnel costs are the most significant component of operating expenses and consist of salaries, benefits, and stock-based compensation expense. Operating expenses also include overhead costs for facilities, including depreciation expense.
Research and Development. We invest heavily in research and development in order to drive user engagement and customer satisfaction on our platform, which we believe helps to drive organic growth of new users. This, in turn, drives additional growth in, and better lifetime value of, our paid subscribers, as well as increased advertising revenue from impressions from our free users. Expenses are primarily made up of costs incurred for the development of new and improved products and features in our applications. Such expenses include employee-related compensation, including stock-based compensation, of engineers, designers, and product managers, in addition to materials, travel and direct costs associated with the design and required testing of our platform. We expect engineers, designers, and product managers to represent a significant portion of our employees for the foreseeable future. We regularly test product improvements with our users. Many of these tests start by making small changes in the product that affect small numbers of users. As the tests evolve, they can require increasing investment and can impact more users. This process of constant testing is how we implement many of our new products and improvements to our platform and, in total, require large investments and involve substantial time and risks to develop and launch. Some of these products and product improvements may not be well received or may take a long time for users to adopt. As a result, the benefits of our research and development investments may be difficult to forecast. We expect to continue to spend a significant portion of our revenues on research and development in the future.
Sales and Marketing. Sales and marketing expenses are expensed as incurred and consists primarily of brand advertising, marketing, digital and social media spend, field marketing, travel, trade show sponsorships and events, conferences, and employee-related compensation, including stock-based compensation for personnel engaged in sales and marketing functions, and amortization of non-revenue generating capitalized software used to promote Duolingo. We expect our sales and marketing expenses will decline as a percentage of revenues over the long-term.
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General and Administrative. General and administrative expenses primarily consist of employee-related compensation, including stock-based compensation, for management and administrative functions, including our finance and accounting, legal, and people teams. General and administrative expenses also include certain professional services fees, general corporate and director and officer insurance, our facilities costs, public company costs to comply with the rules and regulations of the SEC and the Listing Rules of the Nasdaq Global Select Market, and other general overhead costs that support our operations. We expect that our general and administrative expenses will increase in absolute dollars as our business grows. However, we expect that our general and administrative expenses will remain steady or decrease as a percentage of our revenues as our revenues grow faster than these expenses over the long-term.
Interest Income
Interest income consists of income earned on our money market funds included in cash and cash equivalents and on our marketable securities.
Other income (expense), net
Other income (expense), net consists primarily of foreign currency exchange losses and gains losses.
(Benefit) provision for income taxes
The provision for income taxes represents the income tax (benefit) provision associated with our operations based on the tax laws of the jurisdictions in which we operate. These foreign jurisdictions have different statutory tax rates than the United States. Our effective tax rates will vary depending on the relative proportion of foreign to domestic income, changes in the valuation of our deferred tax assets and liabilities, and changes in tax laws.
The following table sets forth our Unaudited Condensed Consolidated Statements of Operations and Comprehensive Loss data, including year-over-year change, for the periods indicated:
Three Months Ended March 31,
(in thousands)20232022% Change
Revenues$115,661 $81,220 42 %
Cost of revenues (1) (2)31,492 21,490 47 
Gross profit84,169 59,730 41 
Operating expenses:
Research and development (1) (2)45,844 29,781 54 
Sales and marketing (1) (2)16,601 14,940 11 
General and administrative (1) (2)30,243 26,856 13 
Total operating expenses92,688 71,577 29 
Loss from operations(8,519)(11,847)(28)
Other income (expense), net182 (312)<100%
Loss before interest income and (benefit) provision for income taxes(8,337)(12,159)(31)
Interest income5,639 33 >100%
Loss before (benefit) provision for income taxes(2,698)(12,126)(78)
(Benefit) provision for income taxes(116)28 <100%
Net loss and comprehensive loss$(2,582)$(12,154)(79)%
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________________
(1)Includes stock-based compensation expenses as follows:
Three Months Ended March 31,
(In thousands)20232022
Cost of revenues
$11 $
Research and development
9,346 3,632 
Sales and marketing
779 348 
General and administrative
10,937 10,600 
Total
$21,073 $14,586 

(2)Includes amortization of capitalized software and depreciation of property and equipment as follows:
Three Months Ended March 31,
(In thousands)20232022
Cost of revenues (a)
$403 $— 
Research and development407 134 
Sales and marketing (a)
398 228 
General and administrative
554 412 
Total
$1,762 $774 
________________
(a) Amortization of capitalized software is recorded to Cost of revenue and Sales and marketing for revenue and non-revenue generating capitalized software, respectively.

The following table sets forth the components of our Unaudited Condensed Consolidated Statements of Operations and Comprehensive Loss for each of the periods presented as a percentage of revenue.
Three Months Ended March 31,
 20232022
Revenues100 %100 %
Cost of revenues27 26 
Gross profit73 74 
Operating expenses:
Research and development40 37 
Sales and marketing14 18 
General and administrative26 33 
Total operating expenses80 88 
Loss from operations(7)(15)
Other income (expense), net— — 
Loss before interest income and (benefit) provision for income taxes(7)(15)
Interest income— 
Loss before (benefit) provision for income taxes(2)(15)
(Benefit) provision for income taxes— — 
Net loss and comprehensive loss(2)%(15)%
Revenues
Revenues increased $34.4 million, or 42%, to $115.7 million during the three months ended March 31, 2023, from revenues of $81.2 million during the three months ended March 31, 2022. The main drivers of the increase were:
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Subscription revenue increased $28.2 million during the three months ended March 31, 2023, primarily due to an increase in the average number of paid subscribers during the periods presented;
Duolingo English Test revenue increased by $1.9 million during the three months ended March 31, 2023 due to an increase in the number of international students taking the Duolingo English Test, driven in part by marketing efforts; and
Other revenue increased $4.5 million during the three months ended March 31, 2023, primarily due to increase in DAUs and average in-app purchase revenue per user.
The increases noted above were partially offset by a decrease in advertising revenue of $0.1 million during the three months ended March 31, 2023. This decrease was driven by advertising pricing declines during the period, partially offset by the increase in DAUs, which resulted in increased advertisements served.
The following table provides the changes in revenues by product type:
Three Months Ended March 31,
(in thousands)20232022Change% Change
Subscription$86,185 $58,010 $28,175 49 %
Advertising11,635 11,748 (113)(1)
Duolingo English Test9,972 8,080 1,892 23 
Other7,869 3,382 4,487 133 
Total revenues$115,661 $81,220 $34,441 42 %
Cost of Revenues and Gross Margin. Total gross margin decreased to 72.8% during the three months ended March 31, 2023 from 73.5% during the three months ended March 31, 2022, respectively. This is primarily due to lower advertising margin driven by lower average revenue per DAU in addition to increased amortization of capitalized software. This was partially offset by higher subscription margins as a higher proportion of our subscriber base has been paying longer than one year, driving a reduction in third-party payment processing fees per subscriber.
The following table provides the change in cost of revenues, along with related gross margins:
Three Months Ended March 31,
20232022
(in thousands)CostsGross MarginCostsGross Margin
Total cost of revenues$31,492 72.8 %$21,490 73.5 %
Operating Expenses
Research and Development. Research and development expense increased $16.1 million, or 54%, to $45.8 million during the three months ended March 31, 2023 from $29.8 million during the three months ended March 31, 2022. The increase was mainly due to:
Increased employee costs from headcount growth of $14.3 million, including stock-based compensation of $5.7 million,
Increased web services and technology costs of $1.4 million,
Increased travel and meal costs of $0.6 million
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Increased other costs of $0.2 million incurred as our headcount grows and we expand our facilities footprint.
These increases were partially offset by decreased contractor costs of $0.4 million.
Research and development continues to be our largest operating expense as we invest in it in order to drive user engagement with and customer satisfaction in our platform. This engagement and satisfaction, we believe, helps to drive organic growth in MAUs and DAUs, growth in, and better retention of, paid subscribers, as well as increased advertising opportunities with free users.
Sales and Marketing. Sales and marketing expense increased $1.7 million, or 11%, to $16.6 million during the three months ended March 31, 2023 from $14.9 million during the three months ended March 31, 2022. This increase was mainly due to an increase in employee costs of $1.0 million due to the growth in headcount, including stock-based compensation of $0.4 million, in addition to increased direct marketing and other expenses of $0.7 million.
Direct marketing spend and other marketing expenses as a percentage of revenue decreased as a result of applying learnings from past years, which enabled us to spend marketing expenses more efficiently.
General and Administrative. General and administrative expense increased $3.4 million, or 13%, to $30.2 million during the three months ended March 31, 2023 from $26.9 million during the three months ended March 31, 2022. The main drivers of this increase were related to the following:
Increased net employee related costs of $1.5 million,including stock-based compensation of $0.4 million,
Increased travel and meals expenses of $0.9 million,
Increased rent related costs incurred to expand to our facilities footprint of $0.3 million,
Other net increases of $0.7 million, due to increased headcount, professional fees, contractor expense, insurance costs, transaction costs and sales and VAT taxes.
Interest Income
Interest income increased $5.6 million during the three months ended March 31, 2023 due to an increase in interest rates earned on our money market funds.
Other income (expense), net
Other income (expense), net increased $0.5 million, during the three months ended March 31, 2023, mainly from the impact from changes in foreign currency rates and proceeds from the sale of capitalized software.
(Benefit) provision for income taxes
For the three months ended March 31, 2023, the Company recorded an income tax benefit of $0.1 million. The income tax benefit recorded in the current period is primarily attributable the excess tax benefits of stock-based compensation activity which occurred during the period.
Liquidity and Capital Resources
Since inception, we have financed operations primarily through revenues and the net proceeds we have received from the issuance of equity.
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As of March 31, 2023, we had $641.1 million in cash and cash equivalents. Our cash and cash equivalents primarily consist of bank deposits and money market funds. Our marketable securities consist of US government treasury and agency securities.
We believe that our existing cash and cash equivalents, and cash flow from operations will be sufficient to support working capital and capital expenditure requirements for at least the next 12 months. Our future capital requirements will depend on many factors, including our subscription growth rate and renewal activity, the timing of cash received from our payment processing platforms, the expansion of our sales and marketing activities, the introduction of new products and the enhancements to existing products, and the current uncertainty in the global markets. We may be required to seek additional equity. If we are unable to raise additional capital or generate cash flows necessary to expand our operations and invest in continued innovation, we may not be able to compete successfully, which would harm our business, operations and financial condition.
A substantial source of our cash from operations comes from deferred revenue, which is included in the liabilities section of our Unaudited Condensed Consolidated Balance Sheet. Deferred revenues consists of the unearned portion of customer billings, which is recognized as revenue in accordance with our revenue recognition policy. As of March 31, 2023, we had deferred revenues of $181.9 million, which is recorded as a current liability and expected to be recognized as revenue in the next 12 months, provided all other revenue recognition criteria have been met.
The following table summarizes our cash flows for the periods presented:
Three Months Ended March 31,
(in thousands)20232022
Net cash provided by operating activities$29,604 $20,627 
Net cash used for investing activities(1,312)(2,444)
Net cash provided by financing activities4,619 5,226 
Net increase in cash and cash equivalents$32,911 $23,409 
Operating Activities
Cash flows from operating activities can fluctuate significantly from period to period due to timing of payments and cash collections. Our largest source of operating cash is cash collection from sales of subscriptions to our users. Our primary uses of cash from operating activities are for personnel expenses, marketing expenses, hosting expenses, and overhead expenses.
Cash provided by operating activities for the three months ended March 31, 2023 increased $9.0 million, or 44%, to $29.6 million. This increase was mainly due to the decrease in net loss in addition to an increase in stock-based compensation expense.
Investing Activities
Cash used in investing activities decreased $1.1 million, or 46%, to $1.3 million for the three months ended March 31, 2023, from $2.4 million for the three months ended March 31, 2022. The decrease is due to decreased capitalization of software development costs and capital expenditures to purchase property and equipment to support office space and site operations. Additionally, proceeds from the sale of capitalized software was included in the current period, but there was no such gain in the prior period.
Financing Activities
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Cash provided by financing activities for the three months ended March 31, 2023 and 2022 was $4.6 million and $5.2 million, respectively, and was proceeds from exercises of stock options.
Critical Accounting Policies and Estimates
Our Unaudited Condensed Consolidated Financial Statements and the related notes thereto included elsewhere in this Quarterly Report on Form 10-Q are prepared in accordance with GAAP. The preparation of Unaudited Condensed Consolidated Financial Statements also requires us to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue, costs and expenses, and related disclosures. We base our estimates on historical experience and on various other assumptions that we believe to be reasonable under the circumstances. Actual results could differ significantly from the estimates made by management. To the extent that there are differences between our estimates and actual results, our future financial statement presentation, financial condition, results of operations, and cash flows will be affected.
There have been no material changes to our critical accounting policies and estimates as compared to those described in “Management’s Discussion and Analysis of Financial Condition and Results of Operations” set forth in our Annual Report on Form 10-K.
Recent Accounting Pronouncements
See Note 1, Basis of Presentation and Note 2, Summary of Significant Accounting Policies in the notes to our Unaudited Condensed Consolidated Financial Statements included in Part I, Item I of this Quarterly Report on Form 10-Q for a discussion of Recent Accounting Pronouncements.
Item 3. Quantitative and Qualitative Disclosures About Market Risk
Interest Rate Risk
As of March 31, 2023, we had $592.6 million of cash equivalents invested in money market funds. Our cash and cash equivalents are held for working capital purposes in addition to future investments in our product. We do not enter into investments for trading or speculative purposes. Our investments are exposed to market risk due to a fluctuation in interest rates, which may affect our interest income and the fair market value of our investments. As of March 31, 2023, a hypothetical 10% relative change in interest rates would not have a material impact on our Unaudited Condensed Consolidated Financial Statements.
Foreign Currency Exchange Risk
Our reporting currency and the functional currency of our wholly owned foreign subsidiaries is the US dollar. Certain of our payment providers translate our payments from local currency into USD at time of settlement, which means that during periods of a strengthening US dollar, our international receipts could be reduced. Our operating expenses are denominated in the currencies of the countries in which our operations are located, which are primarily in the United States and China. Our consolidated results of operations and cash flows are, therefore, subject to fluctuations due to changes in foreign currency exchange rates and may be adversely affected in the future due to changes in foreign exchange rates. In addition, as foreign currency exchange rates fluctuate, the translation of our international receipts into US dollars affects the period-over-period comparability of our operating results and can result in foreign currency exchange gains and losses. To date, we have not entered into any hedging arrangements with respect to foreign currency risk or other derivative financial instruments, although we may choose to do so in the future. A hypothetical 10% increase or decrease in the relative value of the US dollar to other currencies would not have a material effect on our operating results.
Inflation Risk
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Inflationary factors such as increases in costs may adversely affect our results of operations. We do not believe that inflation has had a material effect on our business, financial condition or results of operations to date. If our costs were to become subject to significant inflationary pressures, we may not be able to fully offset such higher costs through price increases. Our inability or failure to do so could harm our business, financial condition or results of operations.
Item 4. Controls and Procedures
Limitations on Effectiveness of Controls and Procedures
Our disclosure controls and procedures and internal control over financial reporting are designed to provide reasonable assurance of achieving their desired objectives. Management does not expect, however, that our disclosure controls and procedures or our internal control over financial reporting will prevent or detect all error and fraud. Any control system, no matter how well designed and operated, is based upon certain assumptions and can provide only reasonable, not absolute, assurance that its objectives will be met. Further, no evaluation of controls can provide absolute assurance that misstatements due to error or fraud will not occur or that all control issues and instances of fraud, if any, within the company have been detected.
Evaluation of Disclosure Controls and Procedures
Our management, with the participation of our principal executive officer and principal financial officer, conducted an evaluation of the effectiveness of the design and operation of our disclosure controls and procedures, as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act, as of the end of the period covered by this Quarterly Report on Form 10-Q. Based on that evaluation, our principal executive officer and principal financial officer have concluded that our disclosure controls and procedures were effective as of the end of the period covered by this Quarterly Report on Form 10-Q to provide reasonable assurance that information required to be disclosed by us in reports that we file or submit under the Exchange Act is (i) recorded, processed, summarized and reported within the time periods specified in the SEC rules and forms and (ii) accumulated and communicated to our management, including our principal executive officer and principal financial officer, as appropriate to allow timely decisions regarding required disclosure.
Changes in Internal Control Over Financial Reporting
There were no changes in our internal control over financial reporting, as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act, during the three months ended March 31, 2023 that materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.
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Part II Other Information
Item 1. Legal Proceedings
From time to time we may be involved in claims and proceedings arising in the course of our business. The outcome of any such claims or proceedings, regardless of the merits, is inherently uncertain. We are not currently party to any material legal proceedings.
Item 1A. Risk Factors
Our business, operations and financial results are subject to various risks and uncertainties, including those described below, that could materially adversely affect our business, results of operations, financial condition, and the trading price of our Class A common stock. You should carefully consider the risks and uncertainties described below, together with all of the other information contained in this Quarterly Report on Form 10-Q, including Part I, Item 2. "Management's Discussion and Analysis of Financial Condition and Results of Operations" and the financial statements and the related notes. If any of the following risks actually occur, it could harm our business, prospects, operating results, and financial condition and future prospects. In such event, the market price of our Class A common stock could decline and you could lose all or part of your investment. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also impair our business operations. This Quarterly Report on Form 10-Q also contains forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those anticipated in the forward-looking statements as a result of factors that are described below and elsewhere in this Quarterly Report.
Risks Related to Our Business and Industry
If we fail to keep existing users or add new users, or if our users decrease their level of engagement with our products or do not convert to paying users, our revenue, financial results and business may be significantly harmed.
The size of our user base and our users’ level of engagement and paid conversion are critical to our success. Our financial performance has been and will continue to be significantly determined by our success in adding, keeping and engaging users of our products and converting them into paying subscribers. We expect that the size of our user base will fluctuate or decline in one or more markets from time to time. If people do not perceive our products to be useful, effective, reliable, and/or trustworthy, we may not be able to attract or keep users or otherwise maintain or increase the frequency and duration of their engagement or the percentage of users that are converted into paying subscribers. There is no guarantee that we will not experience an erosion of our user base or engagement levels. User engagement can be difficult to measure, particularly as we introduce new and different products and services. Any number of factors can negatively affect user stickiness, growth, engagement and conversion, including if:
users increasingly engage with other competitive products or services instead of our own;
user behavior on any of our products changes, including decreases in the frequency and duration of use of our products and services;
users feel that their experience is diminished as a result of the decisions we make with respect to the frequency, prominence, format, size and quality of ads that we display;
users become concerned about our user data practices or other matters related to privacy and the sharing of user data;
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users lose confidence in our ability to teach language or other subjects or have concerns related to security or other factors;
users are no longer willing to pay for subscriptions or in-app purchases;
users have difficulty installing, updating or otherwise accessing our products on mobile devices as a result of actions by us or third parties that we rely on to distribute our products and deliver our services;
we fail to introduce new features, products or services that users find engaging or if we introduce new products or services, or make changes to existing products and services, that are not favorably received;
initiatives designed to attract and keep users and increase engagement are unsuccessful or discontinued, whether as a result of actions by us, third parties or otherwise;
there is a decrease in user stickiness as a result of users no longer being interested in pursuing online language learning or reaching a point where they feel our product cannot advance their language ability;
third-party initiatives that may enable greater use of our products, including low-cost or discounted data plans, are discontinued;
we adopt terms, policies or procedures related to areas such as user data or advertising that are perceived negatively by our users or the general public;
we fail to combat inappropriate or abusive activity on our platform;
we fail to provide adequate customer service to users, marketers or other partners;
we fail to protect our brand image or reputation;
we, our partners, or companies in our industry are the subject of adverse media reports or other negative publicity, including as a result of our or their user data practices;
technical or other problems prevent us from delivering our products in a rapid and reliable manner or otherwise affect the user experience, such as unplanned site outages due to our failure or the failure of third-party systems we rely on, security breaches, distributed denial-of-service attacks or failure to prevent or limit spam or similar content;
there is decreased engagement with our products as a result of internet shutdowns or other actions by governments that affect the accessibility of our products in any of our markets;
there is decreased engagement with our products, or failure to accept our terms of service, as part of changes that we have implemented, or may implement, in the future in connection with regulations, regulatory actions or otherwise;
there is decreased engagement with our products as a result of changes in prevailing social, cultural or political preferences in the markets where we operate; or
there are changes mandated by legislation, regulatory authorities or litigation that adversely affect our products or users.
From time to time, certain of these factors have negatively affected user stickiness, growth and engagement to varying degrees. If we are unable to maintain or increase our user base and user engagement, our revenue and financial results may be materially adversely affected. In addition, we may not experience rapid user growth or engagement in countries that have high mobile device penetration, but due to the lack of sufficient cellular based data networks, consumers rely heavily on Wi-Fi and may
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not access our products regularly throughout the day. Any decrease in user stickiness, growth or engagement could render our products less attractive to users, which is likely to have a material and adverse impact on our revenue, business, financial condition and results of operations. If our user growth rate slows or declines, we will become increasingly dependent on our ability to maintain or increase levels of user engagement and monetization in order to drive revenue growth.
The online language learning industry is highly competitive, with low switching costs and a consistent stream of new products and entrants, and innovation by our competitors may disrupt our business.
The online language learning industry is highly competitive, with a consistent stream of new products and entrants. As a result, new products, entrants and business models are likely to continue to emerge, both in the United States and abroad. It is possible that a new product could gain rapid scale at the expense of existing brands through harnessing a new technology, or a new or existing distribution channel, creating a new or different approach to connecting people or some other means. We compete for learners’ time, attention, and share of wallet not only with other online and app-based language learning platforms, but also with offline forms of language learning. Because of the extensibility of the Duolingo platform beyond language learning, we also compete with language learning assessment providers and literacy platforms and may compete with other kinds of online learning platforms in the future.
Many of the current and potential competitors, both domestically and internationally, have substantially greater financial, technical, sales, marketing and other resources than we do, as well as in some cases, lower costs. Some competitors offer more differentiated products (for example, online learning as well as physical classrooms and textbooks) that may allow them to more flexibly meet changing customer preferences. Some of our competitors may enjoy better competitive positions in certain geographical regions, user demographics or other key areas that we currently serve or may serve in the future, or in their ability to teach certain languages or to teach speakers of certain languages other languages. These advantages could enable these competitors to offer products that are more appealing to users and potential users than our products, to respond more quickly and/or cost-effectively than us to new or changing opportunities, new or emerging technologies or changes in customer requirements and preferences, or to offer lower prices than ours or to offer free language-learning products or services.
There are a number of free online language-learning opportunities to learn grammar, pronunciation, vocabulary (including specialties in areas such as medicine and business), reading and conversation by means of podcasts and mobile applications, audio courses and lessons, videos, games, stories, news, digital textbooks, and through other means, which compete with our products. We estimate that there are thousands of free mobile applications for language learning; free products are provided in at least 50 languages by private companies, universities and government agencies. Low barriers to entry allow start-up companies with lower costs and less pressure for profitability to compete with us. Competitors that are focused more on user acquisition rather than profitability may be able to offer products at significantly lower prices or for free. As free online translation services improve and become more widely available and used, people may generally become less interested in language learning. If we cannot successfully attract users of these free products and convert a sufficient portion of these free users into paying users, our business could be adversely affected. If free products become more engaging and competitive or gain widespread acceptance by the public, demand for our products could decline or we may have to lower our prices, which could adversely impact our revenue and other results.
Potential competitors also include larger companies that could devote greater resources to the promotion or marketing of their products and services, take advantage of acquisition or other opportunities more readily or develop and expand their products and services more quickly than we do. For example, in 2020, Apple released “Translate," an iOS translation app developed by Apple for iOS devices, to translate
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text sentences or speech between several languages. Potential competitors also include established social media companies that may develop products, features, or services that may compete with ours or operators of mobile operating systems and app stores. These social media and mobile platform competitors could use strong or dominant positions in one or more markets, and ready access to existing large pools of potential users and personal information regarding those users, to gain competitive advantages over us. These may include offering different product features, services or pricing models that users may prefer, which may enable them to acquire and engage users at the expense of our user growth or engagement.
If we are not able to compete effectively against our current or future competitors and products or services that may emerge, the size and level of engagement of our user base may decrease, which could materially adversely affect our business, financial condition and results of operations.
Changes to our existing brand and products, or the introduction of a new brand or products, could fail to attract or keep users or generate revenue and profits.
Our ability to keep, increase, and engage our user base and to increase our revenue depends heavily on our ability to continue to evolve our existing brand and products and to create successful new brands and products. We may introduce significant changes to our existing brand and products, or acquire or introduce new and unproven brands, products and product extensions, including using technologies with which we have little or no prior development or operating experience. In addition, we often introduce a new product and delay its monetization until the product is more mature and the user base is better established. We have also invested, and expect to continue to invest, significant resources in growing our products to support increasing usage as well as new lines of business, new products, new product extensions and other initiatives to generate revenue. For example, in 2020, we launched our Duolingo ABC app, which has not yet generated any revenue for us. There is no guarantee that investing in new lines of business, new products, new product extensions and other initiatives will succeed. If our new or enhanced brands, products or product extensions fail to engage users, we may fail to attract or keep users or to generate sufficient revenue, operating margin, or other value to justify our investments, and our business may be materially adversely affected.
We have a limited operating history and, as a result, our past results may not be indicative of future operating performance.
We have a limited operating history, which makes it difficult to forecast our future results. You should not rely on our past quarterly operating results as indicators of future performance. You should take into account and evaluate our prospects in light of the risks and uncertainties frequently encountered by companies in rapidly-evolving markets like ours.
We have had operating losses each year since our inception and we may not achieve or maintain profitability in the future.
We have incurred operating losses each year since our inception and we may not achieve or maintain profitability in the future. Although our revenue has increased each quarter since the first quarter of 2018, there can be no assurances that it will continue to do so. Our operating expenses may continue to increase in the future as we increase our sales and marketing efforts and continue to invest in the development of products and services. These efforts may be costlier than we expect and we cannot guarantee that we will be able to increase our revenue to offset our operating expenses. Our revenue growth may slow or our revenue may decline for a number of other possible reasons, including reduced demand for our products or services, increased competition, a decrease in the growth or reduction in size of our overall market, or if we fail for any reason to capitalize on our growth opportunities. If we do not
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achieve or maintain profitability in the future, it could materially adversely affect our business, financial condition and results of operations.
We have grown rapidly in recent years and have limited operating experience at our current scale of operations. If we are unable to manage our growth effectively, our brand, company culture and financial performance may suffer.
We have experienced rapid growth and demand for our services since inception. We have expanded our operations rapidly and have limited operating experience at our current size. As we have grown, we have increased our employee headcount and we expect headcount growth to continue for the foreseeable future. From December 31, 2018 to March 31, 2023, our headcount grew from approximately 140 employees to over 650 employees. Further, as we grow, our business becomes increasingly complex. To effectively manage and capitalize on our growth, we must continue to expand our sales and marketing, focus on innovative product and content development, upgrade our management information systems and other processes, and obtain more space for our expanding staff. Our continued growth could strain our existing resources, and we could experience ongoing operating difficulties in managing our business across numerous jurisdictions, including difficulties in hiring, training, and managing a diffuse and growing employee base. Failure to scale and preserve our company culture with our growth could harm our future success, including our ability to retain and recruit personnel and to effectively focus on and pursue our corporate objectives. If our management team does not effectively scale with our growth, we may experience erosion to our brand, the quality of our products and services may suffer, and our company culture may be harmed. Moreover, we have been, and may in the future be, subject to legacy claims or liabilities arising from our systems and controls, content or workforce in earlier periods of our rapid development.
Because we have a limited history operating our business at its current scale, it is difficult to evaluate our current business and future prospects, including our ability to plan for and model future growth. Our limited operating experience at this scale, combined with the rapidly-evolving nature of the market in which we operate, substantial uncertainty concerning how these markets may develop, and other economic factors beyond our control, reduces our ability to accurately forecast quarterly or annual revenue. Failure to manage our future growth effectively could have a material adverse effect on our business, financial condition, and operating results.
Our costs are continuing to grow, and some of our investments have the effect of reducing our operating margin and profitability. If our investments are not successful, our business and financial performance could be harmed.
Historically, our costs have increased each year since 2011 and we anticipate that our expenses will continue to increase in the future as we broaden our user base, develop and implement new products, market new and existing products and promote our brands, continue to expand our technical infrastructure, and continue to hire additional employees and contractors to support our expanding operations, including our efforts to focus on privacy, safety, and security. In addition, from time to time we may be subject to settlements, judgments, fines, or other monetary penalties in connection with legal and regulatory developments that may be material to our business. We may also invest in new platforms and technologies. Some of these investments may generate only limited revenue and reduce our operating
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margin and profitability. If these efforts are not successful, our ability to grow revenue will be harmed, which could materially adversely affect our business and financial performance.
Our quarterly operating results and other operating metrics may fluctuate from quarter to quarter, which makes these metrics difficult to predict.
Our quarterly operating results and other operating metrics have fluctuated in the past and may continue to fluctuate from quarter to quarter, which makes them difficult to predict. Our financial condition and operating results in any given quarter can be influenced by numerous factors, many of which we are unable to predict or are outside of our control, including, for example:
the timing, size and effectiveness of our marketing efforts;
the timing and success of new product, service and feature introductions by us or our competitors or any other change in the competitive landscape of our market;
fluctuations in the rate at which we attract new users, the level of engagement of such users and the propensity of such users to subscribe to our brands or to purchase à la carte features;
successful expansion into international markets;
errors in our forecasting of the demand for our products and services, which could lead to lower revenue or increased costs, or both;
increases in sales and marketing, product development or other operating expenses that we may incur to grow and expand our operations and to remain competitive;
the diversification and growth of our revenue sources;
our ability to maintain gross margins and operating margins;
fluctuations in currency exchange rates and changes in the proportion of our expenses denominated in foreign currencies;
changes in our effective tax rate;
changes in accounting standards, policies, guidance, interpretations, or principles;
our development and improvement of the quality of the Duolingo language app and Duolingo English Test, other Duolingo experiences, including, enhancing existing and creating new products, services, technology and features;
the continued development and upgrading of our technology platform;
system failures or breaches of security or privacy;
our ability to obtain, maintain, protect and enforce intellectual property rights and successfully defend against claims of infringement, misappropriation or other violations of third-party intellectual property;
adverse litigation judgments, settlements, or other litigation-related costs;
changes in the legislative or regulatory environment, including with respect to privacy, intellectual property, consumer product safety, and advertising, or enforcement by government regulators, including fines, orders, or consent decrees; and
changes in business or macroeconomic conditions, lower consumer confidence in our business or in the online learning industry generally, recessionary conditions, increased inflation, increased
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interest rates, increased unemployment rates, stagnant or declining wages, political unrest, armed conflicts, or natural disasters.
Any one of the factors above or the cumulative effect of some of the factors above may result in significant fluctuations in our results of operations.
The variability and unpredictability of our quarterly operating results or other operating metrics could result in our failure to meet our expectations or those of analysts that cover us or investors with respect to revenue or other operating results for a particular period. If we fail to meet or exceed such expectations, the market price of our Class A common stock could fall substantially, and we could face costly lawsuits, including securities class action suits.
Our user metrics and other estimates are subject to inherent challenges in measurement, and real or perceived inaccuracies in those metrics may negatively affect our reputation and our business.
We track certain key operational metrics and non-GAAP financial measures, including MAUs, DAUs, paid subscribers, subscription bookings, total bookings, Adjusted EBITDA and free cash flow, to evaluate growth trends, measure our performance, and make strategic decisions. Our user metrics are calculated using internal company data gathered on an analytics platform that we developed and operate, have not been validated by an independent third party and may differ from estimates or similar metrics published by third parties due to differences in sources, methodologies, or the assumptions on which we rely. Our user metrics are also affected by technology on certain mobile devices that automatically runs in the background of our application when another phone function is used, and this activity can cause our system to miscount the user metrics associated with such an account. We continually seek to improve the accuracy of and our ability to track such data, but given the complexity of the systems involved and the rapidly changing nature of mobile devices and systems, we expect to continue to encounter challenges, particularly if we continue to expand in parts of the world where mobile data systems and connections are less stable. In addition, we may improve or change our methodologies for tracking these metrics over time, which could result in unexpected changes to our metrics, including the metrics we publicly disclose. As a result, while any future periods may benefit from such improvement or change, prior periods may not be as accurate or comparable, or we may need to adjust such prior periods. The methodologies used to measure these metrics require significant judgment and are also susceptible to algorithm or other technical errors. In addition, our methodologies for tracking these metrics may change over time, which could result in unexpected changes to our metrics, including the metrics we publicly disclose. If the internal systems and tools we use to track these metrics undercount or overcount performance or contain algorithmic or other technical errors, the data we report may not be accurate. While these numbers are based on what we believe to be reasonable estimates of our metrics for the applicable period of measurement, there are inherent challenges in measuring how our products are used across large populations globally.
Errors or inaccuracies in our metrics or data could also result in incorrect business decisions and inefficiencies. For instance, if a significant understatement or overstatement of active users were to occur, we may expend resources to implement unnecessary business measures or fail to take required actions to attract a sufficient number of users to satisfy our growth strategies. We continually seek to address technical issues in our ability to record such data and improve our accuracy, but given the complexity of the systems involved and the rapidly changing nature of mobile devices and systems, we expect these issues to continue, particularly if we continue to expand in parts of the world where mobile data systems and connections are less stable. If our operational metrics are not accurate representations of our business, or if investors do not perceive these metrics to be accurate, or if we discover material inaccuracies with respect to these figures, our reputation may be significantly harmed, our stock price
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could decline, we may be subject to stockholder litigation, and our business, results of operations, and financial condition could be materially adversely affected.
We rely on third-party platforms such as the Apple App Store and the Google Play Store to distribute our products and collect revenue. If we are unable to maintain a good relationship with such platform providers, if their terms and conditions or pricing changes to our detriment, if we violate, or if a platform provider believes that we have violated, the terms and conditions of its platform, or if any of these platforms loses market share or falls out of favor or is unavailable for a prolonged period of time, our business will suffer.
Our products depend on mobile app stores and other third parties such as data center service providers, as well as third party payment aggregators, computer systems, internet transit providers and other communications systems and service providers. Our mobile applications are almost exclusively accessed through and depend on the Apple App Store and the Google Play Store. While our mobile applications are generally free to download from these stores, we offer our users the opportunity to purchase subscriptions and certain à la carte features through these applications. We determine the prices at which these subscriptions and features are sold. Purchases of these subscriptions and features via our mobile applications are mainly processed through the in-app payment systems provided by Apple and Google. As of March 31, 2023 we paid Apple and Google, as applicable, a meaningful share (generally 15-30%) of the revenue we receive from transactions processed through in-app payment systems. In the three months ended March 31, 2023, we derived 57% of our revenue and 60% of our total bookings from the Apple App Store, and 19% of our revenue and 19% of our total bookings from the Google Play Store. The timing of their payments also may change, which may negatively impact our cash receipts and working capital. While we do not anticipate any interruption in their distribution platforms or ability to accept customer payments, any such disruptions, even temporary, may have material impacts on our business and operations.
We are subject to the standard policies and terms of service of third-party platforms, which govern the promotion, distribution, content and operation generally of apps on the platform. Each platform provider has broad discretion to make changes to its operating systems or payment services or change the manner in which their mobile operating systems function and to change and interpret its terms of service and other policies with respect to us and other developers, and those changes may be unfavorable to us. For example, such changes could limit, eliminate or otherwise interfere with our products, our ability to distribute our applications through their stores, our ability to update our applications, including to make bug fixes or other feature updates or upgrades, the features we provide, the manner in which we market our in-app products, our ability to access native functionality or other aspects of mobile devices, and our ability to access information about our users that they collect. In addition, our distribution agreements with Apple and Google are generally terminable by Apple or Google without cause with 30 days prior written notice (to the extent allowed by applicable local law). Apple and Google may also terminate our agreements with them immediately (unless a longer period is required by applicable law) under certain circumstances, including upon our uncured breach of such agreements. To the extent Apple, Google or other third party platform providers on which we rely make such changes or terminate our agreements with them, our business, financial condition and results of operations could be materially adversely affected.
A platform provider may also change its fee structure, add fees associated with access to and use of its platform, alter how we are able to advertise on the platform, change how the personal information of its users is made available to application developers on the platform, limit the use of personal information for advertising purposes, or restrict how users can share information with their friends on the platform or across platforms. For example, in December 2017, Apple revised its App Store Guidelines to require the disclosure of the odds of receiving certain types of virtual items from “loot boxes” (or similar mechanisms
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that offer a paid license to randomized virtual items) before customers purchase a license for the virtual items, and in May 2019 Google revised its Play Store policies to require similar disclosures. As another example, in April 2021 Apple released an update of iOS that requires its users, on an app-by-app basis, to explicitly opt-in to the use of identifier-for-advertising, a device identifier assigned by Apple to each of its devices and used by advertisers to attribute app installs to advertising campaigns, target users through user acquisition, and deliver targeted ads. This led to a reduction in the use of identifiers, and a more challenging environment for publishers and advertisers on iOS devices.
If we violate, or a platform provider believes we have violated, its terms of service (or if there is any change or deterioration in our relationship with these platform providers), that platform provider could limit or discontinue our access to the platform. A platform provider could also limit or discontinue our access to the platform if it establishes more favorable relationships with one or more of our competitors or it determines that we are a competitor. Any limit or discontinuation of our access to any platform could significantly reduce our ability to distribute our products to users, decrease the size of the user base we could convert into paying users, or decrease the revenues we derive from paying users or advertisers, each of which would materially and adversely affect our business, financial condition and results of operations.
We also rely on the continued popularity, customer adoption, and functionality of third-party platforms. In the past, some of these platform providers have been unavailable for short periods of time or experienced issues with their in-app purchasing functionality. If either of these events recurs on a prolonged, or even short-term, basis or other similar issues arise that impact users’ ability to access our app or access social features, our business, financial condition, results of operations or reputation may be harmed.
We rely on third-party hosting and cloud computing providers, like Amazon Web Services (“AWS”) and Google Cloud, to operate certain aspects of our business. A significant portion of our product traffic is hosted by a limited number of vendors, and any failure, disruption or significant interruption in our network or hosting and cloud services could adversely impact our operations and harm our business.
Our technology infrastructure is critical to the performance of our products and to user satisfaction, as well as our corporate functions. Our products and company systems run on a complex distributed system, or what is commonly known as cloud computing. We own, operate and maintain elements of this system, but significant elements of this system are operated by third-parties that we do not control and which would require significant time and expense to replace. We expect this dependence on third-parties to continue. We have suffered interruptions in service in the past, including when releasing new software versions or bug fixes, and if any such interruption were significant and/or prolonged it could adversely affect our business, financial condition, results of operations or reputation.
In particular, a significant portion, if not almost all, of our product traffic, data storage, data processing and other computing services and systems is hosted by AWS and Google Cloud. AWS and Google Cloud provide us with computing and storage capacity pursuant to an agreement that continues until terminated by either party. The agreements require AWS and Google Cloud to provide us their standard computing and storage capacity and related support in exchange for timely payment by us. We have experienced, and may in the future experience, disruptions, outages and other performance problems due to a variety of factors, including infrastructure changes, human or software errors and capacity constraints. If a particular application is unavailable when users attempt to access it or navigation through a product is slower than they expect, users may stop using the application and may be less likely to return to the application as often, if at all.
Any failure, disruption or interference with our use of hosted cloud computing services and systems provided by third-parties, like AWS or Google Cloud, could adversely impact our business, financial
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condition or results of operations. For example, on December 7, 2021, an outage of the AWS platform caused Duolingo to go offline for over 5 hours. To the extent we do not effectively respond to any such interruptions, upgrade our systems as needed and continually develop our technology and network architecture to accommodate traffic, our business, financial condition or results of operations could be adversely affected. Furthermore, our disaster recovery systems and those of third-parties with which we do business may not function as intended or may fail to adequately protect our critical business information in the event of a significant business interruption, which may cause interruption in service of our products, security breaches or the loss of data or functionality, leading to a negative effect on our business, financial condition or results of operations.
In addition, we depend on the ability of our users to access the internet. Currently, this access is provided by companies that have significant market power in the broadband and internet access marketplace, including incumbent telephone companies, cable companies, mobile communications companies, government-owned service providers, device manufacturers and operating system providers, any of whom could take actions that degrade, disrupt or increase the cost of user access to our products or services, which would, in turn, negatively impact our business. The adoption or repeal of any laws or regulations that adversely affect the growth, popularity or use of the internet, including laws or practices limiting internet neutrality, could decrease the demand for, or the usage of, our products and services, increase our cost of doing business and adversely affect our results of operations.
We derive a portion of our revenues from advertisements. If we are unable to continue to compete for these advertisements, or if any events occur that negatively impact our relationships with advertising networks, our advertising revenues and operating results would be negatively impacted.
We generate advertising revenue from the sale of display and video advertising delivered through advertising impressions. In 2023, approximately 10.1% of our total revenues were derived from advertising. We generally enter into arrangements with the major programmatic advertising networks to monetize our advertising inventory. We need to maintain good relationships with these advertising networks to provide us with a sufficient inventory of advertisements. Online advertising, including through mobile applications, is an intensely competitive industry. Many large companies, such as Amazon, Facebook and Google, invest significantly in data analytics to make their websites and platforms more attractive to advertisers. Our advertising revenue is primarily a function of the number and hours of engagement of our free users and our ability to provide innovative advertising products that are relevant to our users, maintain or increase user engagement and satisfaction with our products, and enhance returns for our advertising partners. If our relationship with any advertising partners terminates for any reason, or if the commercial terms of our relationships are changed or do not continue to be renewed on favorable terms, or if we cannot source high-quality ads consistent with our brand or product experience, we would need to qualify new advertising partners, which could negatively impact our revenues, at least in the short term.
In addition, internet-connected devices and operating systems controlled by third parties increasingly contain features that allow device users to disable functionality that allows for the delivery of advertising on their devices or reduce the ability to provide personalized or targeted advertising, which results in less valuable ads. Device and browser manufacturers may include or expand these features as part of their standard device specifications. For example, when Apple announced that UDID, a standard device identifier used in some applications, was being superseded and would no longer be supported, application developers were required to update their apps to utilize alternative device identifiers such as universally unique identifier, or, more recently, identifier-for-advertising, which simplifies the process for Apple users to opt out of behavioral targeting. Furthermore, laws and regulations may also make it more difficult to deliver personalized or targeted advertising or impose requirements that result in more users
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making elections to block our ability to deliver targeted ads. If users do not elect to participate in functionality that supports the delivery of targeted advertising on their devices, our ability to deliver effective advertising campaigns could suffer, which could cause our business, financial condition, or results of operations to suffer. While the described changes did not result in material adverse impacts to us, the impact of similar potential future operating systems changes or potential future regulation on targeted advertising is highly uncertain.
If we are not able to maintain the value and reputation of our brand, our ability to expand our base of users may be impaired, and our business and financial results may be harmed.
We believe that our brand has significantly contributed to our word of mouth virality, which has in turn contributed to the success of our business. We also believe that maintaining, protecting and enhancing our brand is critical to expanding our base of users and, if we fail to do so, our business, financial condition and results of operations could be materially adversely affected. We believe that the importance of brand recognition will continue to increase, given the growing number of language learning applications, or “apps,” and the low barriers to entry for companies offering language learning products and services. Many of our new users are referred by existing users. Maintaining our brand will depend largely on our ability to continue to provide useful, reliable, trustworthy and innovative products, which we may not do successfully.
Further, we may experience media, legislative, or regulatory scrutiny of our actions or decisions regarding user privacy, encryption, content, contributors, advertising and other issues, which may materially adversely affect our reputation and brand. In addition, we may fail to respond expeditiously or appropriately to objectionable content within our app or practices by users, or to otherwise address user concerns, which could erode confidence in our brand. Maintaining and enhancing our brand will require us to make substantial investments and these investments may not be successful.
Our growth and profitability rely, in part, on our ability to attract and keep users through cost-effective marketing efforts, including through our social media presence and use of social media influencers. Any failure in these efforts could materially adversely affect our business, financial condition and results of operations.
We have increased our marketing expenditures over time in order to attract and keep users and sustain our growth. For the three months ended March 31, 2023 and 2022, our Sales and marketing expenses were $16.6 million and $14.9 million, respectively. Evolving consumer behavior can affect the availability of profitable marketing opportunities. For example, as consumers communicate less via email and more via text messaging, messaging apps and other virtual means, the reach of email campaigns designed to attract new and repeat users (and keep current users) for our products is adversely impacted. To continue to reach potential users and grow our businesses, we must identify and devote our overall marketing activities and expenditures to newer advertising channels, such as mobile and online video platforms as well as targeted campaigns in which we communicate directly with potential, former and current users via new virtual means. For example, in 2021 and 2022, we expanded our activities on the TikTok platform. Generally, the opportunities in and sophistication of newer advertising channels are relatively undeveloped and unproven, and there can be no assurance that we will be able to continue to appropriately manage and fine-tune our marketing efforts in response to these and other trends in the advertising industry. Furthermore, these newer advertising channels often change rapidly and can be subject to disruptions for reasons beyond our control (for example potential US governmental restrictions on the TikTok platform). Any failure to successfully manage our marketing efforts on, or disruptions to,
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social media channels that we have come to depend on for marketing could materially adversely affect our business, financial condition and results of operations.
We are subject to certain risks as a mission-based company.
We believe that a critical contributor to our success has been our commitment to make free language learning available worldwide in an effort to help people throughout the world improve their economic outcomes. The mission of Duolingo is a significant part of our business strategy and who we are as a company. We believe that Duolingo users value our commitment to our mission. However, because we hold ourselves to such high standards, and because we believe our users have come to have high expectations of us, we may be more severely affected by negative reports or publicity if we fail, or are perceived to have failed, to live up to Duolingo’s mission. For example, maintaining a free version of the app that is both effective and enjoyable is central to Duolingo’s mission. As a result, our brand and reputation may be negatively affected by actions we take that are viewed as contrary to that mission, such as features that are only available to paid subscribers or changes to the free offering that are viewed as undermining how fun or effective the free offering is. In these or other circumstances, the damage to our reputation may be greater than to other companies that do not share similar values with us, and it may take us longer to recover from such an incident and gain back the trust of our users.
We may make decisions regarding our business and products in accordance with Duolingo’s mission and values that may reduce our short- or medium-term operating results if we believe those decisions are consistent with the mission and will improve the aggregate user experience. Although we expect that our commitment to Duolingo’s mission will, accordingly, improve our financial performance over the long term, these decisions may not be consistent with the expectations of investors and any longer-term benefits may not materialize within the time frame we expect or at all, which could harm our business, revenue and financial results.
Unfavorable media coverage could materially adversely affect our business, brand image or reputation.
Unfavorable publicity or media reports regarding us, our privacy practices, our social media activities, data security compromises or breaches, product changes, product or service quality or features, litigation or regulatory activity or regarding the actions of our partners, our users, our employees or other companies in our industry, could materially adversely affect our brand image or reputation, regardless of the veracity of such publicity or media reports. If we fail to protect our brand image or reputation, we may experience material adverse effects to the size, demographics, engagement, and loyalty of our user base, resulting in decreased revenue, fewer app installs (or increased app uninstalls), or slower user growth rates. Damage to our brand or reputation could also adversely affect educational institutions’ willingness to accept the Duolingo English Test, which in turn could slow the growth of, or reduce, our revenue from the Duolingo English Test. In addition, if securities analysts or investors perceive any media coverage of us to be negative, the price of our Class A common stock may be materially adversely affected. Any of the foregoing could materially adversely affect our business, financial condition and results of operations.
Our future success depends on the continuing efforts of our key employees and our ability to attract and retain highly skilled personnel and senior management.
We currently depend on the continued services and performance of our key personnel, including Luis von Ahn and Severin Hacker. If one or more of our executive officers or key employees were unable or unwilling to continue their employment with us, we might not be able to replace them easily, in a timely manner, or at all. The risk that competitors or other companies may poach our talent increases as we continue to build our brands and become more well-known. Our key personnel have been, and may continue to be, subject to poaching efforts by our competitors and other internet and high-growth companies, including well-capitalized players in the social media and consumer internet space. The loss
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of key personnel, including members of management as well as key engineering, product development, design and marketing personnel, could disrupt our operations and have a material adverse effect on our business. The success of our brand also depends on the commitment of our key personnel to our mission. To the extent that any of our key personnel act in a way that does not align with our mission, our reputation could be materially adversely affected. See “—Our employees, consultants and third party providers could engage in misconduct that materially adversely affects us.”
Our future success will depend upon our continued ability to identify, hire, develop, motivate, and retain highly skilled individuals across the globe, with the continued contributions of our senior management being especially critical to our success. Competition for well-qualified, highly skilled employees in our industry is intense and our continued ability to compete effectively depends, in part, upon our ability to attract and retain new employees. While we have established programs to attract new employees and provide incentives to retain existing employees, particularly our senior management, we cannot guarantee that we will be able to attract new employees or retain the services of our senior management or any other key employees in the future. Additionally, we believe that our culture and core values have been, and will continue to be, a key contributor to our success and our ability to foster the innovation, creativity and teamwork we believe we need to support our operations. If we fail to effectively manage our hiring needs and successfully integrate our new hires, or if we fail to effectively manage remote work arrangements, our efficiency and ability to meet our forecasts and our ability to maintain our culture, employee morale, productivity and retention could suffer, and our business, financial condition and results of operations could be materially adversely affected.
Finally, effective succession planning is also important to our future success. If we fail to ensure the effective transfer of senior management knowledge and smooth transitions involving senior management across our various businesses, our ability to execute short and long term strategic, financial and operating goals, as well as our business, financial condition, and results of operations generally, could be materially adversely affected.
Our employees, consultants and third party providers could engage in misconduct that materially adversely affects us.
Our employees, consultants and third party providers could engage in misconduct that materially and adversely affects us. Misconduct by these parties could include intentional failures to comply with the applicable laws and regulations in the United States and abroad, report financial information or data accurately or disclose unauthorized activities to us. These laws and regulations may restrict or prohibit a wide range of pricing, discounting and other business arrangements. Such misconduct could result in legal or regulatory sanctions and cause serious harm to our reputation. It is not always possible to identify and deter misconduct by these parties, and any other precautions we take to detect and prevent this activity may not be effective in controlling unknown or unmanaged risks or losses, or in protecting us from governmental investigations or other actions or lawsuits stemming from a failure to comply with these laws or regulations. If any such actions are instituted against us, and we are not successful in defending ourselves or asserting our rights, those actions could result in the imposition of significant civil, criminal and administrative penalties, which could have a significant impact on our business. Whether or not we are successful in defending against such actions or investigations, if any of our employees, consultants or third party providers were to engage in or be accused of misconduct, we could be exposed to legal liability, incur substantial costs, our business and reputation could be materially adversely affected, and we could fail to retain key employees. See “—Unfavorable media coverage could materially adversely affect our business, brand image or reputation.”
If the recognition by schools, governments, and other institutions of the value of technology-based assessment does not continue to grow, or if such institutions reduce their reliance on the
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Duolingo English Test or assessment in general, our ability to generate revenue from our assessment, including our Duolingo English Test, could be impaired.
The success of the Duolingo English Test depends in part upon the continued recognition and acceptance by schools, governments, and other institutions of technology-based assessment, such as the Duolingo English Test, and upon the continued utilization of assessment in general. As a result of the COVID-19 pandemic, in 2020, a number of universities waived standardized test requirements for admissions requirements and some universities plan to phase out requirements for standardized testing altogether. In addition, some have questioned the validity of language assessments taken online. If schools, governments, and other institutions reduce their reliance, or altogether cease to use standardized testing as part of admissions processes or otherwise, or reduce or eliminate reliance on standardized testing, it would have a material adverse effect on our Duolingo English Test business, which could adversely affect our revenues and results of operations.
Similarly, we continually seek to expand the number of schools, governments, and other institutions that accept the Duolingo English Test, including through direct engagement, government tenders, and other channels. If we are unable to do so, or if schools, governments, and other institutions rescind their acceptance of the Duolingo English Test, it may have a material adverse effect on our ability to grow the number of tests taken through the Duolingo English Test. For example, loss of confidence in the Duolingo English Test’s validity, security, or other characteristics could lead to a reduction in the number of accepting institutions, which could in turn reduce the appeal of the Duolingo English Test to test takers and adversely affect our revenues and results of operations. See “—Unfavorable media coverage could materially adversely affect our business, brand image or reputation.”.
We operate in various international markets, including certain markets in which we have limited experience. As a result, we face additional risks in connection with certain of our international operations.
Both our language learning application and the Duolingo English Test are available all over the world. Operating internationally, particularly in countries in which we have limited experience, exposes us to a number of additional risks, including:
operational and compliance challenges caused by distance, language and cultural differences;
the cost and resources required to localize our platform and services, which often requires the