An Ondoku3 (Ondoku-san) alternative without character limits
Ondoku3, known in Japan as 音読さん (Ondoku-san), is a popular online text to speech site: type or paste text, pick a voice, listen and download an MP3. You can try it without an account, free registration gives up to 5,000 characters, and in October 2026 paid plans started at ¥980 a month before tax for 200,000 characters. Commercial use is allowed, with a visible credit on the free plan.
This guide compares Ondoku3 with SuperClonica honestly: when the site is the easier choice, and when an offline engine without character limits suits you better.
What Ondoku3 does well
It is quick, runs in the browser, speaks many languages, reads text from images, and has tips for dictionaries and intonation, which matters a lot for Japanese readings of kanji. For a short MP3 now, with no installation, it is hard to beat.
Where the limits are
Characters are counted per month, so long texts, books or daily videos run into the plan. Free commercial use needs a credit where listeners can see it, and some uses, such as broadcast, podcast distribution, selling materials or work for others, need its Business plan.
No character limit offline
The SuperClonica engine runs the Supertonic 3 model on your own computer, on an ordinary processor, in 31 languages including Japanese. There is no monthly quota: voice a whole book with one command, and the text never leaves your machine. Install it with python -m pip install superclonica-cpu and run superclonica --text-file book.txt --voice F2 --lang ja --output book.mp3.
Anime and character voices
Every catalog voice reads every supported language, so about 190 voices, from narrators to anime and game characters, can read your Japanese text. Each is a small file bought once; the ten stock voices are free and may be used commercially. Any voice page reads a line of 30 to 100 characters free, with no account.
Which to choose
Choose Ondoku3 for a quick MP3 in the browser, image reading or a language SuperClonica lacks. Choose SuperClonica to voice long texts offline with no limit, to use character voices, or to build voices into an app with its API, which has a free tier of 3 minutes a day.