Duolingo, Inc. (DUOL)

Duolingo is a technology company whose mission is to develop the best education in the world and make it universally available. It builds mobile-first, bite-sized, gamified learning products, and its flagship Duolingo App is the world's most popular way to learn languages and the top-grossing Education app on Google Play and the Apple App Store. The company was founded by Luis von Ahn and Severin Hacker, who met at Carnegie Mellon University. As of December 31, 2025, it had more than 900 employees, including more than 430 engineers.

The Duolingo App offers over 250 language courses, plus Math, Music and Chess courses integrated into the app, and is also accessible through a web browser. All course content is free and supported by ads shown at the end of lessons. Paid tiers include Super Duolingo, which is ad-free with additional features and includes a family plan for up to six subscribers, and Duolingo Max, a higher-priced premium tier with AI-powered features such as Roleplay, Explain My Answer and Video Call. The Duolingo English Test, launched in 2016, is an online, on-demand, computer-adaptive English proficiency assessment accepted by over 6,100 education programs, including 24 of the top 25 U.S. undergraduate programs by international enrollment. The company also offers Duolingo for Schools, a web-based classroom tool, and Duolingo ABC, an early literacy app for young children.

The app had more than 130 million monthly active users as of December 31, 2025, and about 9% of them were paid subscribers. About 43 million daily active users had a streak of seven days or longer. Learners span the socioeconomic spectrum worldwide. The Duolingo English Test serves students and professionals who need to demonstrate English proficiency for university admissions, work visas and job applications. The company cites HolonIQ's estimate that consumer spend on language learning, online and offline, will reach about $123 billion by 2027. Growth has been driven mainly by word-of-mouth and brand buzz, supplemented by brand marketing, owned media such as emails and push notifications, targeted paid acquisition, and localized campaigns in markets with low awareness.

Duolingo runs its products on a shared technology infrastructure built on AI, machine learning, data analytics and extensive A/B testing, using data from nearly 2 billion exercises completed daily. It also integrates external AI models, and notes that AI features require increased computing investment. It competes for learners' time and spending with other online and app-based language platforms, offline language learning, language assessment providers, literacy platforms, and math, music and chess learning products. The company relies on trademarks, copyrights, domain names, confidentiality agreements and two patent applications to protect its intellectual property. It is subject to privacy, data protection, consumer protection and child-protection regulation, among others. It is based in Pittsburgh and recruits from top computer science, design and business programs and from other technology hubs.