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

browser.i18n.getUILanguage()

None.

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

let uiLanguage = browser.i18n.getUILanguage();
console.log(uiLanguage);
// e.g. "fr"

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

This page was last modified on ⁨Jul 17, 2025⁩ by MDN contributors.