A private translator: your text never leaves your device
Contracts, medical letters, private messages, work you haven't published yet. Kalila translates them on your own device, so there is no server that receives the text, keeps it or learns from it.
Why most online translators can't be private
A translator that runs in the cloud has to receive your text to translate it: the words travel to the company's servers, are processed there, and the translation comes back. What happens to the text after that — whether it is logged, kept, read by reviewers or used to improve their systems — is decided by that company's privacy policy, and policies change. A good policy is a promise. A translator that never sends the text needs no promise.
How Kalila keeps it private
- The translation runs on your device. On kalila.app/translate and in the browser extension, an open-source translation engine (Mozilla's Bergamot) runs inside your browser. The Mac app uses Apple's on-device translation.
- Only fixed files are downloaded. The first time you use a language, its language file downloads once — the same file for everyone. Nothing about you or your text goes with the request.
- No account, no tracking. No sign-up, no history on a server, no ads. Your text lives in the tab or in the app on your computer, and nowhere else.
- Free, without limits. The translation runs on your device, so it costs us nothing, and there is no daily quota.
Kalila and a cloud translator, side by side
| Kalila | A cloud translator | |
|---|---|---|
| Where the text is translated | On your device | On the company's servers |
| Your text sent over the internet | Never | Every time you translate |
| Account | None | Often required for more text or documents |
| Works without the internet | Yes, after a one-time language download | Usually not on a computer |
| Languages | 58 online and in the extension, 26 in the Mac app | Often 100 or more |
| Documents and photos | Text and web pages | Often PDF, Word and photos too |
Where a cloud translator is better — honestly
Large cloud models are trained on more data and run on big servers. On some language pairs, on long and nuanced text and on rare languages they can translate better than a model small enough to run on your computer. They also translate whole documents and photos, and cover more languages. If your text is not private, use whatever translates it best. When it is private, Kalila is the translator that never sees it.
Don't trust us — check it
- Open kalila.app/translate and translate a sentence once, so the languages download.
- Look at “Requests from this page” under the translator: it lists every request the page makes, live. None of them carries your text.
- Turn off Wi-Fi and translate again. It still works, because the translation happens on your device.
- For a second opinion, open your browser's developer tools, choose the Network tab, and watch what the page sends while you type.
Questions
Is Kalila really free?
Yes. The online translator, the browser extension and the Mac app are free, with no account and no limits on how much you translate.
Does Kalila keep my text?
No. On the website the text lives only in the open tab; close it and it is gone. In the Mac app and the extension, your history and phrasebook stay on your computer, and you can clear them at any time.
Can I use it for confidential documents?
Yes — that is what it is made for. Copy the text into the translator: it is translated on your device and not sent anywhere. Kalila translates text and web pages; it does not open PDF or Word files yet.
How good is the translation?
Good for everyday text in the common languages. On some pairs and on long, nuanced text a large cloud model can do better. Try your own text — it takes a few seconds.
Does it work on my phone?
Yes, kalila.app/translate works in a current browser on a phone, tablet or computer. The browser extension is for Chrome, Edge, Brave and other Chromium browsers on a computer, and the Mac app needs macOS 26.4 or later.