Duolingo, Inc.

Previous wording

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 100 million monthly active users for the three months ended December 31, 2024. 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.

Current wording

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 over 250 total language courses to over 130 million monthly active users for the three months ended December 31, 2025. 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.

Previous wording

We use a freemium business model that relies on a premium subscription offering, advertising, and in-app-purchases (IAPs) to produce revenue. We believe the following key attributes of our freemium subscription business model are core to our success.

Current wording

We use a freemium business model that relies on premium subscription offerings, advertising, and in-app-purchases (IAPs) to produce revenue. We believe the following key attributes of our freemium subscription business model are core to our success.

Previous wording

•Free Users: Since none of our learning content is behind a paywall, anyone can download the Duolingo App, use it for as long as they like, and complete any of our courses free of charge. This has allowed us to scale to more than 100 million MAUs for the three months ended December 31, 2024. These millions of learners provide two benefits to our business model:

Current wording

•Free Users: Since the majority of our learning content is not behind a paywall, anyone can download the Duolingo App, use it for as long as they like, and complete any of our courses free of charge. Our users are composed of both new and reengaged users, which we draw from a large market of learners. We also work to keep existing users engaged in the product. This has allowed us to scale to more than 130 million MAUs for the three months ended December 31, 2025. We have seen these millions of learners provide two benefits to our business model:

Previous wording

◦They become advocates for Duolingo and provide word-of-mouth publicity for our product, which enables our growth and has allowed us to make very selective and efficient marketing investments.

Current wording

◦They become advocates for Duolingo and support our growth through positive word-of-mouth for our product, which enables us to make very selective, efficient, and targeted marketing investments.

Previous wording

◦Our users complete over one billion exercises every day, generating large amounts of data that powers our high-volume A/B testing and novel AI techniques. We use this data and the insights that come from it to continually improve both engagement and efficacy.

Current wording

◦Our users complete nearly 2 billion exercises every day, generating large amounts of data that powers our high-volume A/B testing and novel AI techniques. We use this data and the insights that come from it to continually improve both engagement and efficacy.

Previous wording

•Paid Subscriber Conversion: As learners tend to use our product for months or even years before they decide to subscribe, we enjoy economic benefits from users well into their tenure on the platform. As of December 31, 2024, subscribers made up 8.8% of our average MAUs over the last twelve months as compared to 8.3% of our average MAUs during the year ended December 31, 2023.

Current wording

•Paid Subscriber Conversion: We convert free users to paid subscribers over time. We see stronger conversion from users that recently joined or reengage with the platform, but also see learners who use our product for months or even years before they decide to subscribe. This allows us to enjoy economic benefits from users well into their tenure on the platform. As of December 31, 2025, subscribers made up 9.2% of our average MAUs over the last twelve months as compared to 8.8% of our average MAUs during the year ended December 31, 2024.

Previous wording

Our subscription offerings as of the date of this filing are called Super Duolingo and Duolingo Max. Super Duolingo offers learners additional features to enhance their learning experience. Duolingo Max gives learners access to the existing features of Super Duolingo in addition to incremental features and exercises powered by generative AI technology.

Current wording

Our subscription offerings as of the date of this filing are called Super Duolingo and Duolingo Max. Super Duolingo offers learners additional features to enhance their learning experience. Duolingo Max gives learners access to the existing features of Super Duolingo in addition to incremental features and exercises, such as Video Call.

Previous wording

We also offer in-app purchases, which consist of learners purchasing one-time benefits within the app, such as “Streak Freezes” and “Timer Boosts.”

Current wording

We also offer in-app purchases, (“IAPs”) which consist of learners purchasing one-time benefits within the app, such as “Streak Freezes” and “Timer Boosts.”

Previous wording

In addition to monetizing the Duolingo App, we generate revenue from the Duolingo English Test by charging test takers a one-time fee. University program acceptance is a driver of Duolingo English Test revenue. As of December 31, 2024, over 5,600 education programs around the world accept the Duolingo English Test results as proof of English proficiency for international student admissions, with over 4,700 of those being higher education programs. These include 24 of the top 25 undergraduate programs in the U.S. ranked by international enrollment, as well as top schools such as Yale, Stanford, MIT, Duke and Columbia.

Current wording

In addition to monetizing the Duolingo App, we generate revenue from the Duolingo English Test by charging test takers a one-time fee. University program acceptance is a driver of Duolingo English Test revenue. As of December 31, 2025, over 6,100 education programs around the world accept the Duolingo English Test results as proof of English proficiency for international student admissions, with over 5,300 of those being higher education programs. These include 24 of the top 25 undergraduate programs in the

Previous wording

We had approximately 116.7 million and 88.4 million MAUs for the three months ended December 31, 2024 and 2023, respectively, representing an increase of 32% from the prior year period. We grew MAUs through product initiatives designed to make the app more social and engaging, through marketing, and 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 Duolingo App.

Current wording

We had approximately 133.1 million and 116.7 million MAUs for the three months ended December 31, 2025 and 2024, respectively, representing an increase of 14% from the prior year period. We grew MAUs through a combination of product initiatives and marketing. Product improvements, such as making the app more social and engaging, helped attract new users, retain existing users, and reengage former users, while marketing expanded our reach.

Previous wording

We had approximately 40.5 million and 26.9 million DAUs for the three months ended December 31, 2024 and 2023, respectively, representing an increase of 51% from the prior year period. The DAU / MAU ratio, which we believe is an indicator of user engagement, increased to 34.7% from 30.4% a year ago. We grew DAUs through many of the same marketing and product initiatives as we grew MAUs, such as making the product more fun and engaging.

Current wording

We had approximately 52.7 million and 40.5 million DAUs for the three months ended December 31, 2025 and 2024, respectively, representing an increase of 30% from the prior year period, driven largely by an increase in retention of current users supported by modest growth of new and reengaged users. The DAU / MAU ratio, which we believe is an indicator of user engagement, increased to 39.6% from 34.7% a year ago. We grew DAUs through many of the same product and marketing initiatives as MAUs, with a focus on increasing engagement and encouraging more frequent use.

Previous wording

As of December 31, 2024 and 2023, we had approximately 9.5 million and 6.6 million paid subscribers, respectively, representing an increase of 43% from the prior year period. We grew paid subscribers through product initiatives designed to make Duolingo subscription offerings more appealing, which we believe helped us attract new subscribers and retain existing subscribers.

Current wording

As of December 31, 2025 and 2024, we had approximately 12.2 million and 9.5 million paid subscribers, respectively, representing an increase of 28% from the prior year period. We grew paid subscribers through product initiatives designed to make our subscription offerings more appealing, which helped attract new subscribers and retain existing subscribers.

Previous wording

Subscription Bookings and Total Bookings. Subscription bookings represent the amounts we receive from a purchase of any Duolingo subscription offering. Total bookings include subscription bookings, income from advertising networks for advertisements served to our users, purchases of the Duolingo English Test, and in-app purchases of virtual goods. 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.

Current wording

Subscription Bookings and Total Bookings. Subscription bookings represent the amounts we receive from a purchase of any Duolingo subscription offering. Total bookings include subscription bookings, income from advertising networks for advertisements served to our users, purchases of the Duolingo English Test, and in-app purchases of virtual goods ("IAPs"). 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, the majority of which are twelve months in duration.

Previous wording

For the years ended December 31, 2024 and 2023, we generated $730.7 million and $495.5 million of subscription bookings, respectively, representing an increase of $235.2 million, or 47% from the prior year period. We grew subscription bookings by selling more first-time and renewal subscriptions.

Current wording

For the years ended December 31, 2025 and 2024, we generated $996.3 million and $730.7 million of subscription bookings, respectively, representing an increase of $265.5 million or 36%. Subscription bookings increased, driven by growth in both first-time and renewal subscriptions.

Previous wording

For the years ended December 31, 2024 and 2023, we generated $870.6 million and $622.2 million total bookings, respectively, representing an increase of $248.4 million, or 40% from the prior year period. We grew total bookings primarily through growth in subscription bookings as noted above.

Current wording

For the years ended December 31, 2025 and 2024, we generated $1,158.4 million and $870.6 million total bookings, respectively, representing an increase of $287.8 or 33% from the prior year period. We grew total bookings primarily through growth in subscription bookings as noted above.

Previous wording

We use certain non-GAAP financial measures to supplement our Consolidated Financial Statements, which are presented in accordance with GAAP. These non-GAAP financial measures include Adjusted EBITDA, free cash flow and constant currency. 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, free cash flow and constant currency provide meaningful supplemental information regarding our performance. 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 measures and non-GAAP percentage change in constant currency measures for financial and operational decision-making and as a means to evaluate period-to-period comparisons. 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 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 financial 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.

Current wording

We use certain non-GAAP financial measures to supplement our Consolidated Financial Statements, which are presented in accordance with GAAP. These non-GAAP financial measures include Adjusted EBITDA, free cash flow and constant currency measures. 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, free cash flow and constant currency provide meaningful supplemental information regarding our performance. 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 measures and non-GAAP percentage change in constant currency measures for financial and operational decision-making and as a means to evaluate period-to-period comparisons. 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 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 financial 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.

Previous wording

Adjusted EBITDA. Adjusted EBITDA is defined as net income excluding interest income, income taxes, depreciation and amortization, stock-based compensation expenses related to equity awards, transaction costs related to acquisitions, acquisition earn-out costs, gain on sale of capitalized software, loss on disposal of leasehold improvements and impairment 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 income, the most directly comparable financial measure presented in accordance with GAAP, to Adjusted EBITDA.

Current wording

Adjusted EBITDA. Adjusted EBITDA is defined as net income excluding interest income, income taxes, depreciation and amortization, stock-based compensation expenses related to equity awards, transaction costs related to acquisitions, acquisition earn-out costs and impairment of capitalized software. Beginning in the third quarter of 2025, we updated our definition of Adjusted EBITDA to include integration costs related to acquisitions. We did not incur integration costs in periods prior to 2025. 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.

Previous wording

(1)In addition to stock-based compensation expense of $110.5 million and $95.2 million for the years ended December 31, 2024 and 2023, respectively, this includes costs incurred related to taxes paid on equity transactions as follows:

Current wording

(2)In addition to stock-based compensation expense of $137.4 million and $110.5 million for the years ended December 31, 2025 and 2024, respectively, this includes costs incurred related to taxes paid on equity transactions as follows:

Previous wording

(3)Represents costs incurred related to the earn-out payments on acquisitions, which is included within General and administrative expense within our Consolidated Statements of Operations and Comprehensive Income (Loss).

Current wording

(4)Represents costs incurred related to the earn-out payments on acquisitions, which is included within General and administrative expense within our Consolidated Statements of Operations and Comprehensive Income.

Previous wording

(6)Represents impairment of capitalized software, which is included within Research and development expense within our Consolidated Statements of Operations and Comprehensive Income (Loss).

Current wording

(5)Represents impairment of capitalized software, which is included within Research and development expense within our Consolidated Statements of Operations and Comprehensive Income.

Previous wording

For the years ended December 31, 2024 and 2023, we generated net income of $88.6 million and $16.1 million, respectively, representing an increase of $72.5 million. The increase in net income as compared to the comparative period was due to a combination of our growth in revenue and interest income in addition to a reduction in operating expenses as a percentage of revenue as compared to the prior year period.

Current wording

For the years ended December 31, 2025 and 2024, we generated net income of $414.1 million and $88.6 million, respectively, representing an increase of $325.5 million. Net income for 2025 included a one-time income-tax benefit, net of a return-to-provision adjustment reflecting refinements to our tax calculation methodology, of $256.7 million. The increase in net income, excluding the impact from the valuation allowance, as compared to the comparative period was primarily due to revenue growth, partially offset by higher operating expenses, driven primarily by headcount growth, increased marketing spending, and software and technology costs, including AI costs.

Previous wording

For the years ended December 31, 2024 and 2023, we generated Adjusted EBITDA of $191.9 million and $93.7 million, respectively, representing an increase of $98.3 million. Adjusted EBITDA increased due to a combination of our growth in revenue and a reduction in operating expenses as a percentage of revenue as compared to the prior year periods.

Current wording

For the years ended December 31, 2025 and 2024, we generated Adjusted EBITDA of $305.9 million and $191.9 million, respectively, representing an increase of $113.9 million. Adjusted EBITDA increased as compared to the comparative periods for the reasons noted above in net income, adjusted for increases in stock-based compensation expenses, acquisition costs and depreciation and amortization.

Previous wording

Free Cash Flow. Free cash flow is defined as net cash provided by operating activities, reduced by capitalized software development costs and purchases of property and equipment and increased by taxes paid related to stock-based compensation equity awards, transaction costs related to acquisitions and acquisition earn-out payments as we believe such items 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:

Current wording

Free Cash Flow. Free cash flow is defined as net cash provided by operating activities, less capitalized software development costs and purchases of property and equipment. Prior to the first quarter of 2025, free cash flow added back taxes paid related to stock-based compensation equity awards, acquisition transaction costs, and acquisition earn-out payments. Beginning in the first quarter of 2025, we have aligned our calculation of free cash flow to this definition, and prior period in this Annual Report on Form 10-K have been recast to conform to this presentation. 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:

Previous wording

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 percentage change in constant currency revenues and bookings, 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. 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 for the entire period of related bookings. We calculate constant currency bookings by using current period foreign currency bookings and translating them to constant currency using prior year comparable period exchange rates. The constant currency percentage change for revenues and bookings is calculated by dividing the difference between the constant currency amount and the prior year comparable period amount by the prior year comparable period amount.

Current wording

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 percentage change in constant currency revenues and bookings, 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. 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 translating current period foreign currency revenues using prior-year exchange rates applied consistently over the full revenue recognition period. We calculate constant currency bookings by using current period foreign currency bookings and translating them to constant currency using prior year comparable period exchange rates. The constant currency percentage change for revenues and bookings is calculated by dividing the difference between the constant currency amount and the prior year comparable period amount by the prior year comparable period amount.

Previous wording

We generate revenues primarily from the sale of subscriptions. The term-length of our subscription agreements are primarily monthly or annual, with the family plan offered as an annual subscription. We also generate revenue from advertising, the in-app sale of virtual goods, and the Duolingo English Test, as well as from Duo’s Taquería.

Current wording

We generate revenues primarily from the sale of subscriptions. The term-length of our subscription agreements are primarily monthly or annual, with the family plan offered as an annual subscription. We also generate revenue from advertising, the in-app sale of virtual goods, and the Duolingo English Test. We may run experiments that result in a different mix of revenue from these levers in the future.

Previous wording

Cost of revenues predominantly consists of third-party payment processing fees charged by various distribution channels in addition to hosting fees and generative AI costs. To a much lesser extent, cost of revenues includes customer support costs, such as contractor fees, wages and stock-based compensation for certain employees working in customer support. It also includes the amortization of revenue generating capitalized software, and depreciation of certain property and equipment.

Current wording

Cost of revenues predominantly consists of third-party payment processing fees charged by various distribution channels in addition to hosting fees and Artificial Intelligence (“AI”) costs. To a much lesser extent, cost of revenues includes customer support costs, such as contractor fees, wages and stock-based compensation for certain employees working in customer support. It also includes the amortization of revenue generating capitalized software, and depreciation of certain property and equipment.

Previous wording

We intend to continue to invest additional resources in our infrastructure 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.

Current wording

We intend to continue to invest additional resources in our infrastructure to expand the capabilities of our platform and allow our users to realize the full benefit of our products. The level, timing, and relative investment in these areas could affect our cost of revenues in the future.

Previous wording

Research and Development. We invest heavily in research and development to create new products and product features that help us grow our user base, engage our users, monetize our users, and teach our 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 during the preliminary product development stage. 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, required testing of our platform and depreciation of certain property and equipment. We expect engineers, designers, and product managers to represent a significant portion of our employees for the foreseeable future. We typically capitalize a small portion of research and development costs once the product has reached application development phase, mostly consisting of wages, each period into capitalized software when the work is specific to launching a new product, or making major upgrades to our existing products or platforms. 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.

Current wording

Research and Development. We invest heavily in research and development to create new products and product features that are intended to help us grow our user base, engage our users, monetize our users, and teach our users. This, in turn, can impact the growth in, and 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 during the preliminary product development stage. 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, required testing of our platform and depreciation of certain property and equipment. We expect engineers, designers, and product managers to represent a significant portion of our employees for the foreseeable future. We typically capitalize a portion of research and development costs once the product has reached application development phase, mostly consisting of wages, each period into capitalized software when the work is specific to launching a new product, or making major upgrades to our existing products or platforms. 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 impact resulting from our research and development investments may be difficult to forecast.

Previous wording

Interest income consists of income earned on our money market funds included in cash and cash equivalents and income earned and net accretion on our marketable securities.

Current wording

Interest income consists of income earned on our cash and money market funds included in cash and cash equivalents and income earned and net accretion on our marketable securities.

Previous wording

Other (expense) income, net consists primarily of foreign currency exchange gains and losses.

Current wording

Other income (expense), net consists primarily of foreign currency exchange gains and losses.

Previous wording

The provision for income taxes represents the income tax provision associated with our operations based on the tax laws of the jurisdictions in which we operate. In addition to the U.S., we also operate in foreign jurisdictions that have different statutory rates. 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.

Current wording

Income taxes represent the tax impact associated with our operations under the tax laws of the jurisdictions in which we operate. In addition to the U.S., we also operate in foreign jurisdictions that have different statutory rates. 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.

Previous wording

Revenues increased by $216.9 million, or 41%, to $748.0 million during the year ended December 31, 2024, from revenues of $531.1 million during the year ended December 31, 2023. The main drivers of the increase were:

Current wording

Revenues increased by $289.6 million, or 39%, to $1,037.6 million during the year ended December 31, 2025, from revenues of $748.0 million during the year ended December 31, 2024. The main drivers of the increases were:

Previous wording

•Subscription revenue increased by $202.8 million, or 50%, to $607.5 million during the year ended December 31, 2024, primarily due to an increase in the average number of paid subscribers during the period;

Current wording

•Subscription revenue increased $265.9 million, or 44%, to $873.4 million during the year ended December 31, 2025, primarily due to an increase in the average number of paid subscribers during the period;

Previous wording

(1) Other revenue is comprised mainly of Advertising, Duolingo English Test, and In-App Purchases.

Current wording

(1) Other revenue is comprised mainly of Advertising, Duolingo English Test, and IAPs.

Previous wording

Research and Development. Research and development expense increased by $40.9 million, or 21%, to $235.3 million during the year ended December 31, 2024 from $194.4 million during the year ended December 31, 2023. The increase was mainly due to:

Current wording

Research and Development. Research and development expense increased by $71.0 million, or 30%, to $306.3 million during the year ended December 31, 2025 from $235.3 million during the year ended December 31, 2024. The increase was mainly due to:

Previous wording

•Increased travel and other costs of $2.0 million.

Current wording

•Increased travel and other costs of $2.6 million.

Previous wording

Research and development continues to be our largest operating expense as we test and experiment with new products and product features and improve existing ones to drive engagement and efficacy. Increased engagement and efficacy, we believe, help drive organic growth in MAUs and DAUs, growth in, and better retention of, paid subscribers, as well as increased advertising opportunities with free users.

Current wording

Research and development continues to be our largest operating expense as we test and experiment with new products and product features and look to improve existing ones to drive engagement and efficacy. Increased engagement and efficacy, we believe, help drive organic growth in MAUs and DAUs, growth in, and better retention of, paid subscribers, as well as increased advertising opportunities with free users.

Previous wording

Sales and Marketing. Sales and marketing expense increased by $14.7 million, or 19%, to $90.5 million during the year ended December 31, 2024 from $75.8 million during the year ended December 31, 2023.

Current wording

Sales and Marketing. Sales and marketing expense increased by $35.2 million, or 39%, to $125.7 million during the year ended December 31, 2025 from $90.5 million during the year ended December 31, 2024.

Previous wording

•Increased direct marketing and other expenses of $11.2 million; and

Current wording

•Increased direct marketing and other expenses of $25.8 million;

Previous wording

•Increased personnel costs of $3.5 million driven primarily by the growth in headcount, including increased stock-based compensation expense of $1.0 million.

Current wording

•Increased personnel costs of $6.8 million driven primarily by the growth in headcount, including increased stock-based compensation expense of $1.6 million; and