Learn Japanese · 日本語の旅

Most apps teach one thing. Kotori teaches them all together.

Flashcards, grammar, reading, listening, sentence mining. Kotori unites them into one adaptive system, where every lesson sharpens the next.

Invite-only private beta

日read

聞listen

語recall

書write

One connected system

Your progress should not live in five disconnected apps.

A word you missed in review can become a reading passage tomorrow. A grammar point you unlocked can show up in listening. Every activity feeds one shared model of what you know.

Flashcards app

knows your vocab

Grammar site

knows your rules

Reading tool

knows your texts

Kotori

knows all of it, at once

How it works

One adaptive journey, replanned every day.

Sit down, study what matters most right now, and let the loop close itself.

1Assess

It learns your map

Every answer updates a shared estimate for words, kanji, and grammar, so your progress becomes a living model instead of a pile of due cards.

2Plan

It plans the day

Kotori mixes overdue review, the next unlock, and the right exercise format for your current mastery band.

3Weave

It connects the dots

What you mine from reading can seed review. A shaky grammar point can resurface inside listening. Nothing learned in one place is wasted.

Everything in one place

Six ways to practice. One brain behind them.

Each mode works on its own and writes back to the same adaptive model the moment you finish.

Smart Review 復習

Spaced repetition schedules each item by your real recall strength, then lets weak memories surface before they fade.

feeds every other mode

Reading 読解

Graded passages bring vocabulary and grammar back in context, with support close at hand when a sentence gets sticky.

surfaces words you know

JLPT Prep 試験

Practice realistic sections from N5 upward and see which sub-skills still stand between you and a stronger score.

targets your weak bands

Grammar 文法

Short explanations and guided examples unlock when they are useful, then keep appearing where they belong.

unlocks new practice

Sentence Mining 採集

Turn useful sentences into study material, so the Japanese you actually care about becomes part of the curriculum.

seeds tomorrow's reviews

Practice Drills 練習

Listening, pairs, particles, pronunciation, radicals, and speed drills sharpen one skill without splitting your data.

logs back to your map

The science

Built on memory research, not vibes.

Two well-studied ideas do the heavy lifting: spaced repetition to fight forgetting, and a per-item mastery model to choose how, not just when, you practice.

Spaced repetition beats the forgetting curve

Reviewing an item right as recall starts to fade resets the curve flatter each time. Kotori times every review to that moment.

Mastery-aware, not one-size-fits-all

Low confidence gets gentle multiple-choice; high confidence earns harder recall and variety. The format adapts as you do.

One signal, every surface

Because review, reading, grammar, and mining all write to the same model, a mistake anywhere updates everywhere.

Forgetting curvewith vs. without review

Studying with KotoriNo review

Learning

Multiple choice

Familiar

Typed recall

Mastered

Mixed & speed

Meet Kotori

A study companion, not a guilt machine.

"I'll sit with you, cheer the small wins, and never shame you for a missed day."

Kotori keeps the desk calm: no weaponized streaks, no noisy pressure, just the next small step when you are ready.

Invite-only · Private beta

Ready to make every lesson count twice?

Kotori is opening slowly to keep the experience excellent. Join the waitlist, or jump the line with an invite code from a friend in the beta.

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