Blog · 2026-10-30
A Private Translation Extension
A private translation extension for Chrome, Firefox and Edge - with the free engines or your own key, no OpenImmersive server in between; no analytics in the extension; a self-hosted LibreTranslate option; and optional local masking of emails, phone numbers and API keys.
Most browser translators send the page you are reading to their own servers first. A private translation extension should do the opposite: send text only to the engine you choose, keep your keys in your browser, and let you hide personal details before anything leaves your computer. OpenImmersive Translator (openimmersive.ai) is a free, open-source private translation extension built that way, for Chrome, Firefox and Edge.
What makes it a private translation extension
- No server of ours in between. With the free engines or your own key, each request goes from your browser straight to the engine you picked. No OpenImmersive server sits in between. The Standard and Premium AI tiers are the exception: they run through our server and need an account.
- No analytics in the extension. The extension has no analytics, ads or tracking code, and the source code (AGPL-3.0) is on GitHub for anyone to check.
- Your keys stay local. API keys you add are kept in the browser's local storage and are only sent to their own provider.
Choose where your text goes
| Option | Where the text is sent |
|---|---|
| Free Google, Microsoft or MyMemory engine | That engine only, no account |
| Your own DeepL, OpenAI or DeepSeek key | That provider only, billed to you |
| LibreTranslate | The instance URL you enter, for example one you host yourself |
For the strictest setup, run LibreTranslate on your own machine or server, choose LibreTranslate in the settings and enter its address. Your text then never reaches a third-party translation service at all.
Mask personal data before it is sent
Turn on sensitive-data masking (beta, off by default) in the settings. Before a paragraph goes to any engine, the extension finds emails, phone numbers, bank card numbers, national ID numbers and API keys (sk-..., ghp_..., AKIA...) in your browser, swaps them for placeholders, and puts the originals back when the translation returns. The masked values are never sent. Card numbers must pass a Luhn check, so ordinary figures and years are left alone.
How to set it up
- Install OpenImmersive Translator from the Chrome Web Store, Firefox Add-ons or Edge Add-ons.
- In the settings, pick your engine: a free one, your own key, or your LibreTranslate address.
- Turn on sensitive-data masking if you translate emails, tickets or internal pages.
- Open a page and press
Alt+T. The translation appears under each paragraph, with the original kept.
The one exception
The optional Standard and Premium AI tiers are different: they send text to openimmersive.ai, need an account and use credits. If you want a fully private translation extension, simply do not choose them; nothing else in the extension connects to openimmersive.ai.
FAQ
Does it translate completely offline? Only if your LibreTranslate instance runs on your own computer. Otherwise the text goes to the engine you chose.
Is the private translation extension free? Yes. The extension, the free engines and LibreTranslate cost nothing; with your own key you pay that provider directly.
Can I read the code? Yes, it is open source under AGPL-3.0.
How does it compare with Immersive Translate? See the open-source Immersive Translate alternative page for a feature-by-feature comparison, including where Immersive Translate is the better fit.