Translator | Mandarin Stack

The first translation downloads an offline Bergamot model (~50 MB for 中文 → English, ~33 MB for English → 中文) plus a ~5 MB WebAssembly runtime. Models are streamed directly from Mozilla's Firefox Translations bucket — we don't host them.

After this one-time download, translation works fully offline. Cancel if you're on a metered connection.

Translator help

Direction

Pick 中文 → EN to translate Chinese into English, or EN → 中文 for the reverse. The Swap button exchanges source and translation.

First-time download

The first translation in each direction downloads the model files (~50 MB zh→en, ~33 MB en→zh) and the Bergamot WebAssembly runtime. We don't host these — they stream directly from Mozilla's Firefox Translations bucket. The browser cache + service worker keep them around so subsequent translations are instant and work offline.

Shortcuts

Cmd/Ctrl + Enter — translate immediately.
The textarea auto-translates after a short pause once the engine is ready.

Privacy

Translation runs entirely in your browser. The source text never leaves the page. Mozilla's bucket only sees the model-file GETs.

Quality

These are the same models Firefox uses for in-browser translation. Quality is solid for everyday prose, weaker on idioms, names, and very short fragments. Use the Dictionary for word-level lookups.

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