Creative GenerationReplaces Human LaborVerified
Reviewed and published by trentmaziarz, March 21, 2026. Discovered and drafted by our automated research pipeline.
Duolingo uses generative AI to write lesson exercises, dialogues, and entire language courses. Human experts set the rules — the target language, skill level, and grammar topic — and the AI produces the content for human review. In April 2025, Duolingo launched 148 new courses built primarily this way, roughly doubling its total course offerings in about one year.
Details
Disclosed in a June 2023 blog post, Duolingo's system has Learning Designers write a structured prompt — specifying language, Common European Framework of Reference (CEFR) proficiency level, grammar focus, and lesson theme — and a generative AI model then produces batches of exercises that humans review and edit before publication. CEO Luis von Ahn stated in 2025 that content creation is now "close to 100%" AI-generated. The April 2025 course launch was significant: the first 100 Duolingo courses took 12 years to build manually, while 148 new courses were created in approximately one year using AI. In February 2026, Duolingo also replaced its flagship Spanish and French courses with new AI-generated versions.
Products affected
Duolingo
Sources & Evidence
Company Disclosure
Other practices by Duolingo
Customer SvcDuolingo uses an AI chatbot (powered by a company called Decagon) to handle the majority of customer support requests for the Duolingo English Test. The AI fully resolves about 80% of chat inquiries without any human involvement, answering questions about test registration, scores, and institutional acceptance.Data AnalysisDuolingo uses a machine learning model to decide, in real time, whether to show each individual user an advertisement, a subscription offer, or neither — predicting which choice is most likely to generate revenue from that specific person at that moment. The system was credited with generating tens of millions of dollars in additional annual revenue.Data AnalysisDuolingo uses a machine learning algorithm to decide which push notification to send each user, at what time, and how often — optimizing for the messages most likely to get a lapsed learner back into the app. The system was published as research in 2020 and was shown to increase the number of daily active users by 0.5% and improve retention of new users by 2%.
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