How to Completely Remove Firefox from Your Computer

Most uninstalls leave traces behind — leftover folders, cached data, saved profiles, and registry entries that quietly persist after you think Firefox is gone. If you're troubleshooting a broken installation, switching browsers for good, or doing a clean reinstall, knowing how to fully remove Firefox matters.

Here's what a complete removal actually involves, and why the standard uninstall often isn't enough.

Why a Standard Uninstall Leaves Firefox Behind

When you uninstall Firefox through your operating system's default method — Control Panel on Windows, dragging to Trash on macOS — the core application files are removed, but Firefox deliberately preserves your user profile. This includes:

• Bookmarks, passwords, and history
• Extensions and themes
• Cookies and cached website data
• Preference files and configuration settings

Mozilla does this intentionally so your data survives a reinstall. But if your goal is a completely clean slate, those leftover files need to be found and deleted manually.

How to Completely Remove Firefox on Windows 🖥️

Step 1: Run the Standard Uninstaller

Go to Settings → Apps → Installed Apps, find Mozilla Firefox, and select Uninstall. Follow the prompts. This removes the core application but not your profile data.

Step 2: Delete the Remaining Profile Folder

After uninstalling, navigate to this folder and delete it entirely:

C:Users[YourUsername]AppDataRoamingMozillaFirefox 

The AppData folder is hidden by default. To access it, open File Explorer, click View, and enable Hidden items — or type %AppData% directly into the address bar and press Enter.

Also check:

C:Users[YourUsername]AppDataLocalMozillaFirefox 

Delete both folders if they exist.

Step 3: Clean Up Registry Entries (Advanced)

Residual registry entries are harmless for most users but worth removing for a truly clean system. Open the Registry Editor by pressing Win + R, typing regedit, and pressing Enter.

Search for and delete any remaining entries under:

• HKEY_CURRENT_USERSoftwareMozilla
• HKEY_LOCAL_MACHINESoftwareMozilla

Only do this if you're comfortable editing the registry. Incorrect changes to the registry can cause system issues. Back up the registry before making any edits.

Optional: Use a Third-Party Uninstaller

Tools like Revo Uninstaller or Geek Uninstaller automate the leftover-file and registry cleanup process. They scan for remnants after the standard uninstall and let you remove them in one step. This is a practical option for users who don't want to manually hunt through AppData folders or the registry.

How to Completely Remove Firefox on macOS 🍎

Step 1: Quit Firefox and Move It to Trash

Make sure Firefox isn't running, then drag the Firefox application from your Applications folder to the Trash. Empty the Trash.

Step 2: Remove the Profile and Support Files

The app deletion alone leaves behind profile data. Manually delete these folders:

To reach the Library folder, open Finder, hold Option, click Go in the menu bar, and select Library. It's hidden by default.

Delete each of these locations if they exist.

How to Completely Remove Firefox on Linux

On Debian/Ubuntu-based systems installed via the package manager:

sudo apt remove firefox sudo apt purge firefox 

The purge command removes configuration files that remove alone leaves behind.

For profile data stored in your home directory:

rm -rf ~/.mozilla/firefox 

If Firefox was installed as a Snap package:

sudo snap remove firefox 

Snap installations store data separately — check ~/snap/firefox and remove that directory as well if it persists after removal.

What Gets Left Behind If You Skip These Steps

For most users, leftover profile data is harmless if Firefox is gone for good. The risk is primarily storage use and the fact that a fresh Firefox reinstall will pick up the old profile automatically — which defeats the purpose of a clean reinstall.

The Variable That Changes Everything

How thorough you need to be depends entirely on why you're removing Firefox. A user doing a clean reinstall to fix a corrupted profile needs to remove the profile folder but probably doesn't need to touch the registry. A system administrator wiping a shared machine needs full removal including all user profiles across accounts. Someone switching browsers permanently may not care about leftover files if storage isn't a concern.

The steps above cover the complete removal path — but which steps actually matter for your situation depends on your OS, your reason for uninstalling, and how clean you need the system to be.