Translate text
Translate between English and nine other languages with a model that runs in your browser.
- Runs in your browser — your text is never sent anywhere
- No sign-up, no quotas, free to use as often as you like
How it works
Every mainstream translation service sends your text to a server, which is worth thinking about when the text is a contract clause, a medical letter, a legal notice or an internal message. This runs the translation model on your own machine instead.
It is slow the first time
Each language pair is its own model of roughly 105 to 130 MB, downloaded once and then cached by your browser. English to Spanish and Spanish to English are separate downloads. Translation itself takes a few seconds per paragraph on your own processor.
How good is it
These are the Helsinki-NLP open translation models. On plain prose — emails, documentation, articles — they are genuinely useful and often very close to the commercial services. They are weaker on idiom, humour, proper nouns and technical vocabulary, and they translate sentence by sentence, so they cannot use context from earlier in the text to resolve an ambiguity.
When not to rely on it
Anything legal, medical or safety-critical needs a human translator, and that is true of every machine translation including the paid ones. Use this to understand something or to draft, not to publish something binding.
Why these languages
Each pair costs a separate model download, so the list covers the most widely used ones rather than everything. The models are published under permissive licences (Apache 2.0, and CC BY 4.0 for a few pairs) that allow commercial use, which is what makes them usable on a free site at all — several better-known multilingual models are licensed for non-commercial use only.
Translate text — questions
Is my text sent anywhere?
No. The model is downloaded to your browser and the translation happens on your device.
Why is the first translation slow?
The model for that language pair is about 105 to 130 MB and is fetched once, then cached.
How accurate is it?
Good on plain prose, weaker on idiom, names and technical terms. Never rely on machine translation for legal or medical text.
Why only these languages?
Each pair is a separate download. The list covers the most widely used ones with a licence that permits use here. Every pair translates to or from English.