Change Language on Mozilla Firefox


If you want to change Firefox language you must first download it because if want to change it directly it will have no effect. Currently this is only working way to change Mozilla Firefox Language if you don’t want to uninstall and then install again Firefox.



Downloading and installing Mozilla Language Pack:

So, go here and download your language by clicking “Install Language Pack”

mozilla language

Click on “Add to Firefox” Button:

firefox button

And then click on Install Now button as you can see:


Then restart your Firefox!

How to Change Firefox Language:

1. Go to Top Left Corner >> Firefox >> Options >> Options:

firefox menu


Go on Tab Content and then click on Choose… .



Click on Installed language then move it up on first position.

installed language in firefox

That is not all, if you press ok and restart your Firefox the language will be the same,  you have to follow the next steps to complete changing.


Go to address Bar, insert this about:config then and hit enter.

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 In the search filed of new  windows insert this code general.useragent.locale and press enter.

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Double click ongeneral.useragent.locale:



And now you see and insert box that you have to modify value from [ ] of language that you’ve installed:

mozilla firefox language change


If you don’t want to reinstall Mozilla Firefox this is only working way to change language on Mozilla Firefox.

Please comment and let me know if it worked normal.

5 Comments on "Change Language on Mozilla Firefox"

  1. nilesh says:

    not work in my case

    have latest firefox 25

  2. Vyti says:

    It worked, thanks.

  3. michael h says:

    doesn’t work for me- still crap ghetto Russian. Problem is w Russian Windows, its all pirate, never has Eng menus and lunatics don’t believe in AV here, so everything is infected. I installed FF ion this comp- dopes must have removed and installed Russian version.

  4. Manuil says:


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