Momiji is built on the work of people who publish Japanese language data for everyone to use. This page lists the data Momiji uses and the licences it is used under.
Momiji's dictionary, the words in its flashcards, anime word lists and sentence decks, and the offline dictionary in the Momiji browser extension come from the JMdict dictionary files. Kanji readings, meanings, stroke counts, school grades and frequency ranks come from the KANJIDIC2 files. These files are the property of the Electronic Dictionary Research and Development Group, and are used in conformance with the Group's licence, the Creative Commons Attribution-ShareAlike 4.0 licence.
Momiji reorganizes this data for its database and for the browser extension. Those adapted versions, including the dictionary files packaged in the extension, are shared under the same licence.
The stroke order diagrams in the kanji and kana drawing practice come from KanjiVG, copyright Ulrich Apel, used under the Creative Commons Attribution-ShareAlike 3.0 licence.
The anime word lists and the anime frequency ranks shown in the dictionary and the browser extension are Momiji's own, counted from the subtitles of the series in Momiji's anime library.
JLPT levels on words are estimates. The Japan Foundation and Japan Educational Exchanges and Services, which run the JLPT, don't publish official word lists for the current test.
Sentence decks use OpenAI's models to pick which dictionary word is meant when a word could be several, and to translate sentences when you ask. See the privacy policy for what is sent.
If you publish data Momiji uses and something here is wrong or missing, please let us know.