Credits

KanjiVG

Stroke shapes and stroke order of the kanji and kana. The strokes redistributed by Kotojutsu remain under the same licence.

© Ulrich Apel and contributors. Creative Commons Attribution-ShareAlike 3.0 (CC BY-SA 3.0). Project website

JMdict

Flashcard dictionary: written forms, readings, French and English meanings, word frequency. Kotojutsu's dictionary, derived from it, remains under the same licence.

© Electronic Dictionary Research and Development Group. Creative Commons Attribution-ShareAlike 4.0 (CC BY-SA 4.0). Project website

KANJIDIC2

JLPT N4 to N1 kanji decks: meanings, readings, stroke count and frequency of each kanji.

© Electronic Dictionary Research and Development Group. Creative Commons Attribution-ShareAlike 4.0 (CC BY-SA 4.0). Project website

Jonathan Waller's JLPT lists

Split of kanji and words by JLPT level (N5 to N1). There is no official list: these lists, also used by Jisho, are the reference.

© Jonathan Waller; matched to JMdict by Stephen Kraus (yomitan-jlpt-vocab). Creative Commons Attribution (CC BY). Project website

French Wiktionary

French meanings of the Japanese words in the flashcard dictionary.

© the French Wiktionary contributors, extracted by kaikki.org (wiktextract, Tatu Ylonen). Creative Commons Attribution-ShareAlike 4.0 (CC BY-SA 4.0). Project website

Dela Gothic One, Zen Kaku Gothic New, Klee One

Typefaces, served directly by the site.

© artakana (Dela Gothic One), Yoshimichi Ohira (Zen Kaku Gothic New), Fontworks (Klee One). SIL Open Font License 1.1. Project website

gpt-oss-120b

Language model behind Densha, the AI assistant of the lessons and grammar.

OpenAI, run by Groq. Apache License 2.0. Project website

SpeechGen

Audio of the single kana (あ, か, ア…), in every voice.

SpeechGen.io. Commercial licence included in all plans. Project website

VOICEVOX

Japanese voices "Female" and "Male", chosen in the settings.

VOICEVOX:No.7 (No.7製作委員会), VOICEVOX:玄野武宏 (ViRVOX Project). Each voice's terms of use, which require this credit. Project website

WanaKana

Romaji-to-kana conversion while typing.

© the WanaKana contributors. MIT License. Project website

Review algorithm

FSRS (Free Spaced Repetition Scheduler), reimplemented for Kotojutsu with the default parameters published by the open-spaced-repetition project (MIT licence).