How the Furigana Generator works

How to use it

1. Paste Japanese text (up to 10,000 characters).
2. Choose which kanji get furigana.
3. Check the underlined words and tap any wrong reading to fix it.
4. Print on A4, or copy as ruby HTML, Aozora style, brackets or hiragana.

The first time, the tool downloads a dictionary of about 13 MB. After that it works offline.

Is this furigana generator free?

Yes. It is free and needs no sign-up.

Kanji a Japanese child learns by grade

Can it convert kanji to furigana by school grade?

Yes. In “Show furigana for”, choose from “Kanji above Grade 1” to “Kanji above Grade 6 (elementary)”, or “Kanji outside the Jōyō list only”.

Japanese elementary schools teach 1,026 kanji in a fixed order (the official grade list). “Kanji above Grade 3” means furigana on every word that contains at least one kanji taught in Grade 4 or later. The whole word gets furigana, not just that kanji.

Jōyō kanji (2,136) are what Japanese adults are expected to read. “Outside the Jōyō list only” adds furigana to rare kanji only.

Names and words not in the dictionary get no furigana. City and prefecture names use the official readings.

Accuracy and the dotted underline

A dotted underline means the tool is not sure: one-kanji words, words the dictionary split apart, and words with two common readings (such as 行って and 開けて).

We compared the tool with human-made furigana in seven children’s stories on Aozora Bunko (1,604 readings, measured on 2026-09-24). Readings without an underline matched 96.9% of the time (826 of 852). Underlined readings matched 81.9% (484 of 591); 41% of the compared readings were underlined.

FAQ

Why is there no JLPT filter?

The JLPT has not published official kanji lists since its 2010 revision, so any N5–N1 list is unofficial. We use the official Japanese school grade list and the Jōyō list instead.

Is my text sent anywhere?

No. The analysis runs inside your browser. The only download is the dictionary file from this site, and it contains none of your text.

How do I fix a wrong reading?

Tap the word in the preview and type the reading in hiragana. The correction is saved on your device and used for your next texts.

Notes and your data

• Your text, settings and corrections are saved only in this browser (localStorage, keys furigana_*) and never sent anywhere.
• Readings come from a dictionary and can be wrong. Check them before you share a printout.
• Romaji uses Hepburn with long-vowel marks (tōkyō).

Feedback box (in Japanese; you can write in English). We read every message but do not reply.

Site-wide about and disclaimer and privacy policy.

Changelog

• 2026-09-24 Published
• 2026-11-05 Questions added