Firefox - How to change language settings?

August 2016

Firefox - How to change language settings?

If for some reason you want to change the Firefox language (without re-installing the web browser):

Method 1

  • In the address bar of Firefox, type 'about: config' then press "enter" to access the options of Firefox.
  • In the search bar just below, enter the following string: general.useragent.locale
  • Right-click it and click on "Modify", then enter "en-US" to set it to English.
  • Here's a list of the different language codes:
  • Confirm with OK and restart your browser.

Method 2

See also :

This document entitled « Firefox - How to change language settings? » from CCM ( is made available under the Creative Commons license. You can copy, modify copies of this page, under the conditions stipulated by the license, as this note appears clearly.