Last Updated on February 17, 2026
The Mozilla Firefox web browser is a popular alternative to the built in Microsoft Edge web browser that comes with Windows. It has some unique features that other browsers don’t offer, including enhanced tracking protection and extensive customization options. Carrying your personal browser configuration on a portable drive allows you to work securely across multiple computers without leaving private data behind.
Firefox Portable Edition is a portable version of the Firefox web browser packaged as a portable application so you can take your bookmarks, extensions and saved passwords with you on a flash drive or other device. This setup keeps your browsing profile completely isolated from the host operating system. Public computers or shared work machines will not retain your session history once you disconnect your drive
1. Download and Extract the Installation Package
To install Firefox Portable, just download the portable package installer and then double click it. Select the target location on your portable drive where you wish to install the browser and click OK. A FirefoxPortable directory will be created there and all the necessary application files will be installed onto your removable media.
2. Launch the Portable Browser
To start Firefox Portable, double click the FirefoxPortable.exe file where you installed it on your portable drive. The program launches directly from the drive without writing temporary runtime files to the host system. Then, use it just like you would a local copy of Firefox.
3. Locate Your Local Firefox Profile Directory
If you’re using a local copy of Firefox, you may wish to just copy your local Firefox settings right into Firefox Portable. Your local Firefox profile on modern Windows systems is stored in C:\Users\username\AppData\Roaming\Mozilla\Firefox\Profiles\ or accessible by typing %APPDATA%\Mozilla\Firefox\Profiles\ directly into the File Explorer address bar. Open that directory to locate your active default profile folder.
4. Copy Your Profile Settings to the USB Drive
Run Firefox Portable once so it generates its default data folders, then close the browser completely. Copy the contents of your local profile folder, excluding cache directories, directly into the FirefoxPortable\Data\profile directory on your flash drive. Then delete the file FirefoxPortableSettings.ini within the FirefoxPortable\Data\settings directory if there is one so the browser accepts your imported settings.
5. Address Antivirus False Positive Alerts
Some security software programs like Avast or Windows Defender may occasionally flag the portable application launcher as a potential threat. This is due to generic heuristics detection in security products that misidentify NSIS based application launchers as trojans. The portable package is safe to run as long as you download it directly from a verified source.
Click here to download Mozilla Firefox Portable Edition.
