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  2. Add-ons
  3. Browser extensions
  4. JavaScript APIs
  5. i18n
  6. i18n.getUILanguage()

i18n.getUILanguage()

Gets the UI language of the browser. This is different from i18n.getAcceptLanguages which returns the preferred user languages.

See the Internationalization page for a guide on using this function.

Syntax

js
browser.i18n.getUILanguage()

Parameters

None.

Return value

string. The browser UI language code as an i18n.LanguageCode.

Examples

js
let uiLanguage = browser.i18n.getUILanguage();
console.log(uiLanguage);

// e.g. "fr"

Browser compatibility

Chrome
Edge
Firefox
Opera
Safari
Firefox for Android
Safari on iOS
getUILanguage
Chrome – Full support
Chrome 35 (Release date: 2014-05-20)
footnote Full support
Edge – Full support
Edge 14 (Release date: 2016-08-02)
footnote Full support
Firefox – Full support
Firefox 47 (Release date: 2016-06-07)
footnote
footnote Firefox 55 and earlier returns a language tag that's separated with the underscore character instead of hyphen, see bug 1374552.
Opera – Full support
Opera 22 (Release date: 2014-06-03)
footnote Full support
Safari – Full support
Safari 14 (Release date: 2020-09-16)
footnote Full support
Firefox for Android – Full support
Firefox for Android 48 (Release date: 2016-08-02)
footnote Full support
Safari on iOS – Full support
Safari on iOS 15 (Release date: 2021-09-20)
footnote Full support

Tip: you can click/tap on a cell for more information.

Full support
See implementation notes.

Note: This API is based on Chromium's chrome.i18n API. This documentation is derived from i18n.json in the Chromium code.

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