Duolingo stock research: engagement, subscribers and evidence

Dated source, not a current verdict

This worksheet starts from Duolingo's annual report for the year ended 31 December 2025. It is a historical reading exercise, not a claim that the report is the latest available information. Before making a current assessment, locate later filings and read them alongside this starting point. No live price, valuation or GrowthIntel rating is asserted here.

Do not treat every user as a subscriber

The report distinguishes user activity from paid subscribers and describes limitations in measuring operating metrics. Its paid-subscriber definition excludes free trials and non-paying family-plan members. Record those definitions before comparing a subscriber count with an engagement measure.

Research questions: are the observations measured at period end or averaged across a period? Does a change represent new users, returning users or retention? Do definitions stay consistent between documents? A larger total on its own cannot answer these questions.

Build a bridge from activity to economics

Investigate the relationship between engagement, paid conversion, recognised revenue and spending. Do not presume that an improvement in one produces the same improvement in another. A useful evidence table separates each measure, its period and its source.

Write an alternative explanation for an apparent improvement, then locate evidence that could distinguish it from your preferred explanation. Consider what a change in pricing, product mix or acquisition spending would mean for the interpretation, without asserting that such a change occurred.

Leave a reviewable conclusion

Finish with three columns: what the document establishes, what you inferred and what remains unknown. Link the relevant pages and note later material that needs checking. A refreshed web page does not refresh a historical filing.

This worksheet is educational, not personalised advice, an earnings forecast or a recommendation to buy or sell Duolingo. GrowthIntel is not affiliated with or endorsed by the company. The account-free demo illustrates a workflow using sample data and is not the source of a current company assessment.

Primary sources

• Duolingo: 2025 Form 10-K, official filing page
• Duolingo: 2025 annual report on SEC EDGAR

Source links were reviewed on 19 October 2026. A review date does not make a historical document current. External organisations do not endorse this guide.

Try the research process

Explore GrowthIntel with illustrative sample data, or download the research-note worksheet. Neither provides a current buy recommendation.

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