How to Change the Default Languages in Mozilla Firefox

Tell Firefox which language you prefer when viewing webpages

Updated February 21, 2020

Some websites can be rendered in several different languages, depending on their configuration and your web browser's abilities and settings. Firefox, which supports over 240 global dialects, provides the ability to specify which languages you prefer to use when viewing web content.

Before rendering text on a page, Firefox first validates whether or not it supports your preferred languages in the order that you specified them. If possible, the page's verbiage is then displayed in your preferred language. Not all web pages are available in all languages.

How to Specify Preferred Languages in Firefox

Setting and modifying Firefox's list of preferred languages can be done quickly. See the steps below:

In Firefox, select the hamburger (3 horizontal bars) at the top right corner of the menu bar.

You can also type about:preferences into the Firefox address bar.
Select Options.
In General preferences, scroll down to the Language and Appearance section.
Under Language, select your desired language under Choose the languages used to display menus, messages, and notifications from Firefox by selecting Search for more languages.
In Firefox Language Settings, the browser's current default language is shown in order of preference. To choose another language, select Select a language to add.
Scroll through the alphabetical language list and select the language of your choice. To move it into the active list, select Add.

Your new language should now be added to the list. By default, the new language displays first in order of preference. To change its order, use the Move Up and Move Down buttons accordingly. To remove a specific language from the preferred list, select it and select Remove.

When you are satisfied with your changes, select OK to return to Firefox's preferences. Once there, close the tab or enter a URL to continue your browsing session.