Add-ons
Over deze add-on
Adds a Translate button to the message header. One click translates the subject and body of the message you are reading into your language, right in place; click again to show the original. Select part of a message and pick Translate selection from the right-click menu to translate only that part.
In the compose window, a Translate reply button translates what you wrote into the language of the message you are answering, or any language you pick. Quoted text and your signature are left alone, formatting and links stay in place, and Ctrl+Z undoes it.
Bring your own API key for one of these providers:
Privacy
How it works
Shortcuts: Ctrl+Shift+X translates the message, Ctrl+Shift+E opens Translate reply.
Setup: open the add-on's Preferences, pick a provider, paste the key (plus region for Microsoft, folder ID for Yandex), and choose your target language.
Open source (MPL-2.0): GitHub
In the compose window, a Translate reply button translates what you wrote into the language of the message you are answering, or any language you pick. Quoted text and your signature are left alone, formatting and links stay in place, and Ctrl+Z undoes it.
Bring your own API key for one of these providers:
- DeepL - free tier: 500 000 characters/month
- Microsoft Translator - free tier: 2 000 000 characters/month
- Google Cloud Translation - 500 000 characters/month free with billing enabled
- Yandex Translate - trial grant
Privacy
- Message text is sent to the provider you chose only when you click Translate.
- Your API key is stored locally in Thunderbird and sent only to that provider.
- No other servers, no telemetry, no account.
How it works
- Translates only the text; formatting, links, images, and attachments are left untouched.
- Detects the source language automatically; if the message is already in your language, it says so instead of calling the provider.
- Quoted replies and signatures are skipped by default; a setting includes them.
- Translating a large message asks first; the threshold is adjustable in the settings.
- A running translation is cancelled by clicking the button again.
- The 200 most recent translations are cached locally, so reopening a message costs nothing.
- With DeepL, the settings show how much of this month's quota is used.
Shortcuts: Ctrl+Shift+X translates the message, Ctrl+Shift+E opens Translate reply.
Setup: open the add-on's Preferences, pick a provider, paste the key (plus region for Microsoft, folder ID for Yandex), and choose your target language.
Open source (MPL-2.0): GitHub
