How do I translate selected text in Firefox?

Sonic Translate translates selected text with a keyboard shortcut: select, press Ctrl+E, and the translation appears in a popup next to your selection. The Firefox build (Firefox 109+) exists, but its Mozilla Add-ons listing is not live yet — today you can use Sonic Translate in Chrome. Firefox's built-in translator only offers selected-text translation through the right-click menu.

How does the shortcut work in Firefox?

Once the listing is live, the flow is identical to Chrome's:

1. Select the text you want to translate on any webpage.
2. Press Ctrl+E. A popup opens next to your selection with the original text, the translation, speaker buttons for both, a copy button, and a short dictionary preview.
3. Press Shift+E instead if you want the full side panel with definitions, synonyms, and your translation history.
4. Press Escape to close the popup or panel.

The defaults are the same on Windows, macOS, and Linux, and you can change the shortcut to any two-key combination in Options. Sonic Translate covers 109 languages and is powered by Google Translate — see the feature page for details.

Doesn't Firefox already translate selected text?

Yes, but only with the mouse. Firefox's built-in translation can translate a selection through the right-click menu; there is no keyboard shortcut for it, and users have been asking for one on Mozilla Connect. Sonic Translate adds that missing shortcut.

The reverse is also true: Sonic Translate only translates text you select. For full-page translation, Firefox's built-in translator is the right tool.

Where do I get Sonic Translate for Firefox?

The Firefox listing is coming to Mozilla Add-ons — it is not live yet. The extension is built for Firefox 109 and later, and once the listing goes live the Ctrl+E flow above will work exactly as it does in Chrome today. You can already use Sonic Translate in Chrome from the Chrome Web Store — see translating selected text in Chrome.

Where won't the shortcut work?

Browser-internal pages block all extensions, so the shortcut can't respond on Firefox's about: pages (settings, new tab) or the built-in PDF viewer. On regular webpages, select the text and press Ctrl+E.