Japanese that actually clicks.
Kana, radicals, kanji with etymology, vocabulary — one connected study system built for the long game.
Sun and moon together — two sources of light combining to make brightness. One of the clearest pictographic recipes in the language.
Explore kanji →What's in Kotsu
Five interconnected modules, each building on the last.
Hiragana
ひらがなThe 46 fundamental sounds of Japanese. Every word can be written here.
Katakana
カタカナThe angular twin — used for loanwords, emphasis, and foreign names.
Radicals
部首The building blocks of kanji. Learn these and kanji stop looking like noise.
Kanji N5–N3
漢字Essential kanji with etymology, readings, and example compounds.
Vocabulary
語彙Everyday words and phrases — the symbols made immediately useful.
Parts become meaning.
Every kanji is assembled from smaller pieces. Once you see the logic, you can read thousands of characters by feeling rather than memorizing.
How Kotsu works.
Course Tree
A trunk for required order, branches for nearby ideas. Follow the numbers.