Mastermind Japanese Is the Adaptive Mind for Studying Japanese
Mastermind learns what you know, concept by concept, and that model sharpens the more you study — so each session can focus on what is most useful for you to learn next. The current focus is JLPT N5 with various study modes and content, with more coming as Mastermind matures.
Mastermind Japanese is an app built by Jason Kobayashi in Tokyo.
What Makes Mastermind Japanese Different
Concept-Level Tracking
Each study item is connected to specific concepts. Your answers update concept XP, so weak or uncertain areas can come back at a useful time.
Study at the Right Level
Mastermind uses the Mind Map to decide whether to review, reinforce, or introduce a nearby concept, keeping each session close to what you're ready to learn next.
Short Session Friendly
Short sessions still count. Each answer helps Mastermind decide what to review, repair, or stretch next.
How It Works
Start Learning Right Away
Answer a few questions. Mastermind estimates your current concept XP.
The Right Next Step
Mastermind chooses what comes next based on what you know and what you're ready to learn, so you don't have to decide.
Track Readiness Across the Concepts You've Learned
See your concept progress over time and keep momentum toward practical Japanese fluency.
Beta Access
Join the Beta
Try the current beta build with full access to current JLPT N5 content.
- Adaptive study engine
- Full access to current JLPT N5 content
- Session progress tracking
Study Stack
Mastermind uses recognition, listening, sentence building, context, and progress tracking so you study the same concepts in more than one way.
What You Train With
The current beta mixes several live study surfaces so you meet the same ideas from different directions.
Sentence Recognition
Adaptive multiple-choice questions check whether you understand the Japanese sentence in context.
Kanji Writing
For supported kanji, draw the character by hand, check recognition locally, and build a lifetime correct count.
Listening
Some cards play the audio first, so you listen and recall before seeing the written Japanese.
Sentence Building
Arrange Japanese pieces into the right order to build a sentence.
Vocabulary Check
A focused vocabulary check reinforces a word's reading, meaning, and example usage when it needs more direct attention.
Concept Map Feedback
Per-concept XP tracking and the Mind Map show what is opening up, what is weak, and where to study next.
Product Facts
- Mastermind Japanese is a Japanese learning web app built by Jason Kobayashi in Tokyo.
- The Mind Map organizes Japanese into connected concepts, then adapts study based on your progress with each one.
- The first live version covers JLPT N5 in full, with a complete 521-concept Mind Map and a growing library of curated study content.
- Study includes adaptive sessions, listening, speaking, sentence building, kanji writing, verb study, and vocabulary checks.
- The current beta is free and open now.
© 2026 Jason Kobayashi