Duolingo

Duolingo builds a learning app for languages, math, music and chess, offering free learning alongside Super Duolingo and Duolingo Max subscriptions. Super removes advertising; Max includes AI features such as Roleplay and Explain My Answer. Its AI-powered Video Call lets learners practice conversation with the character Lily and is also available to most new Super subscribers. The Duolingo English Test provides an online English proficiency exam, accepted by more than 6,100 institutions at the end of 2025.

Founded in 2011 by Carnegie Mellon engineers Luis von Ahn and Severin Hacker, Duolingo remains led by von Ahn as CEO. Its engineering research connects learning science with personalization: half-life regression models vocabulary forgetting from practice histories to help select words for review. Birdbrain, introduced in 2020, estimates learner knowledge and exercise difficulty, helping assemble lessons suited to each learner. These contributions address both what to practice and how challenging that practice should be.

Duolingo’s freemium business combines subscriptions with advertising, test purchases and in-app purchases. The company reported an average of 58.7 million daily active users in Q2 2026 and 12.7 million paid subscribers at quarter-end. In 2026, it acquired London animation and motion-design studio Animade, expanding its Design Studio’s capacity for product storytelling, character animation and interactive experiences.