Mozilla Firefox Portable 155.0.0.0 for Windows

Mozilla Firefox Portable 155.0.0.0 is a version of the Firefox browser for Windows packaged to run from a folder or USB stick without installation. Download Mozilla Firefox Portable if you want to carry your browser, bookmarks and extensions between computers or use Firefox on a PC where you cannot install software.

Quick facts

• Version: 155.0.0.0
• Packaged by: John T. Haller (PortableApps.com)
• Browser developer: Mozilla
• Platform: Windows
• Licence: free, based on open-source Firefox (Mozilla Public License 2.0)
• Size: about 181.00 MB according to catalogue data

How the portable edition works

A normal Firefox installation writes its program files to Program Files and keeps your profile, with bookmarks, passwords, history and extensions, inside the Windows user folder. The portable package, maintained by John T. Haller as part of the PortableApps.com project, puts both the browser and the profile into one folder and starts Firefox through a small launcher that points it there. The result can live on a USB stick, an external drive or a cloud-synced folder: plug it into another Windows PC, start it, and you get your own browser with your own settings, leaving little behind on the host machine. It is the same Firefox engine Mozilla releases, first released in 2002, with the same add-ons and privacy features; the difference is only in packaging. This version follows its own numbering on the portable side, while Mozilla's current stable line is newer, so check for updates regularly.

How to set it up

1. Get the package from PortableApps.com, the publisher of the portable edition; regular Firefox is available on mozilla.org.
2. Run the self-extracting file and choose a folder or your USB drive as the destination.
3. Start FirefoxPortable.exe from that folder.
4. Sign in to a Mozilla account if you want to sync with other Firefox copies.
5. Update it from the portable menu or the PortableApps.com platform, not the normal Firefox installer.

Requirements

Mozilla's system requirements for this generation of Firefox list Windows 10 or later, a 1 gigahertz (GHz) or faster processor, 1GB of RAM for the 32-bit version or 2GB of RAM for the 64-bit version, and 500MB of hard drive space. A fast USB drive makes a big difference to start-up time.

Safety

A browser profile on a USB stick contains saved passwords and cookies; if you lose the stick, you lose them to whoever finds it. Set a Primary Password in Firefox settings, and avoid running your portable browser on public computers you do not trust, because a compromised host can still read what you type. Release notes for Firefox itself are on firefox.com.

Price

Free, like Firefox.

Pros and cons

• Pro: no installation, runs from any folder or drive.
• Pro: bookmarks and extensions travel with you.
• Pro: same engine and add-ons as regular Firefox.
• Con: slower start from cheap USB sticks.
• Con: updates are handled separately from Mozilla's installer.
• Con: risk of losing a stick with saved passwords.

Alternatives

For a regular installation, Firefox ESR offers long-term support and Firefox Developer Edition targets web developers. Other browsers on our site include Waterfox, Pale Moon, Mullvad Browser and Microsoft Edge.