Japanese audio and video to text

Standard Japanese and regional speech

Standard Japanese, as heard in news and most business meetings, is the easiest input. Strong regional speech such as Kansai-ben, Tohoku or Kyushu dialects is harder, and the model tends to write it in a more standard form or to miss words. Casual speech with fillers like えーと and あのー may keep or drop them unpredictably.

Kanji, kana and punctuation

Japanese mixes kanji, hiragana and katakana, and has no spaces between words. Many words sound identical, so the model may pick the wrong kanji, for example in 橋 and 箸. Names of people and companies can carry unusual readings. The text uses 。 and 、, and line-by-line editing is the quickest way to fix them.

What speakers of Japanese use it for

Meeting minutes (議事録) for work, recorded university lectures, interviews and research recordings, podcasts, and captions for YouTube or streaming clips. Because there are no word boundaries, a text transcript is also easier to search than a recording when you need to find where a name or a number was said.

Which model works best for Japanese

Japanese is one of the languages Whisper-family models have seen the most speech in, so the small model can give a reasonable first draft from clear audio. That is not a promise of accuracy: it still slips on names, numbers, jargon and overlapping or noisy speech, so proof-read anything you will publish or rely on.

On tryscriptorium.com the no-account preview and regular accounts run the small model (the larger medium and large-v3 models run when you self-host Scriptorium).

Japanese is among the languages Whisper saw a lot of, so clean single-speaker audio works well even on the small model. Overlapping speakers, fast business jargon and names are the weak spots. For long recordings with many specialised terms, self-hosting with large-v3 improves the kanji choices.

Subtitles and captions in Japanese

Japanese subtitles read best at about 13 to 20 characters per line, with breaks at phrase or particle boundaries so a word is not split. Many subtitle styles leave out the final 。 or replace it with a space, which a find and replace on the exported SRT can handle. UTF-8 SRT and VTT files show kanji and kana correctly in VLC and YouTube.

The uploader is set to Japanese

The upload box on this page transcribes as Japanese, so the recogniser does not have to guess the language from the first seconds. If the recording is in another language or switches languages, use Audio to text, which detects the language automatically. Automatic transcription is a draft and no accuracy figure is promised: check names, numbers and anything you will rely on.