Learn a language by mastering it, one step at a time

Free courses in Mandarin Chinese, Spanish, English, French, Italian, Portuguese and German. Take a placement quiz, then learn words and grammar in an order where each lesson unlocks only once you have mastered what it builds on.

Spaced review brings every word back right before you would forget it. Everything runs in your browser and progress stays on your device. No account, no ads in the way.

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Courses

How it works

  1. Placement. Five quick questions per band. Get four right and the whole band is marked as known, so you never start below your level.
  2. Skill map. Each course is a graph of small concepts: groups of words, grammar points, and for Mandarin, tones and strokes. A concept unlocks when its prerequisites are mastered.
  3. Mastery. A concept counts as mastered after a streak of correct answers at a comfortable speed. Mistakes reset the streak, not your progress.
  4. Spaced review. Each word gets its own review schedule (the FSRS algorithm). About a third of every session is review.
  5. Mastery checks. Every 50 XP you get a short check on things you mastered earlier. Miss one and it goes back into practice.

FAQ

What is mastery-based learning?

You only move on once you have shown you know something: a run of correct answers at a steady speed. New lessons unlock when the lessons they build on are mastered, and spaced review brings each word back before you forget it.

Do I need an account?

No. Progress is saved in your browser. You can export it to a file and import it on another device.

Which languages can I learn?

Mandarin Chinese (HSK 1 and 2), Spanish (2,000 words, A1 to B1), English for speakers of Spanish, Portuguese and Chinese, and starter courses in French, Italian, Portuguese and German.

Is it free?

Yes. Lessons, word pages and practice are free. The content comes from openly licensed sources and lessons written for this site.