Firefox
Free, open-source web browser from the non-profit Mozilla
- Version
- 159.0
- Released
- October 27, 2026
- Size
- 90 MB (Windows installer)
- License
- MPL-2.0 · Open source
About Firefox
Firefox is the free, open-source browser from Mozilla, the non-profit that has been building for an open web since 2003. It runs Mozilla's own Gecko engine, which makes it the only major browser on Windows, macOS and Linux that is not built on Google's Chromium. Real competition in browser engines keeps the web healthier for everyone.
Privacy is the headline feature, and it works out of the box. Enhanced Tracking Protection blocks ad trackers, cryptominers and fingerprinters by default. Total Cookie Protection keeps every site's cookies in their own jar, so advertisers cannot follow you from site to site. Firefox even translates pages locally on your device instead of sending the text to a cloud service.
The daily-driver features are all here. Sync carries your tabs, bookmarks, passwords and history across Windows, macOS, Linux, Android and iOS. On desktop and Android, the extension catalog is huge, including full content blockers like uBlock Origin. Picture-in-Picture pops video into a floating window, reader mode strips pages down to clean text, and tab groups plus vertical tabs keep heavy sessions organized.
Version 159.0 (October 27, 2026) moves saved passwords into the sidebar by default and introduces Smart Window, which can watch a page for changes such as price drops or restocks and send you a desktop notification when something moves.
Two decades in, the project is still maintained by the Mozilla Foundation with help from a global community of contributors. The code is public under the MPL 2.0 license, anyone can audit it, and the browser funds itself mainly through search deals rather than your data. On Linux, Firefox is also available from most distribution repositories, Flathub and Snap, and organizations can pick the ESR channel for about a year of security fixes without feature changes.
Honest verdict: if you want a browser that answers to a non-profit rather than an advertising company, Firefox is the obvious choice. A few sites are still tuned for Chromium first, so an occasional page misbehaves, but for everyday browsing, streaming and work it keeps up with everything else. Completely free, and no account is needed just to browse.
Image credits: Firefox 157.0 on Linux and Private Browsing in Firefox 157.0 by Exploraz, CC BY-SA 4.0 and MPL 2.0 respectively.
Key Features
Enhanced Tracking Protection
Blocks ad trackers, cryptominers and fingerprinters by default, no setup needed.
Total Cookie Protection
Keeps every site's cookies in their own jar, so trackers cannot follow you across the web.
Sync across devices
Tabs, bookmarks, passwords and history follow you between desktop and mobile with a free Mozilla account.
Extensions and themes
On Windows, macOS, Linux and Android, a large add-on catalog includes full content blockers like uBlock Origin, plus themes to restyle the browser.
Pros & Cons
Pros
- Syncs across Windows, macOS, Linux, Android and iOS
- Completely free and open source, backed by a non-profit
- The only major desktop browser not based on Chromium
- Strong tracking protection enabled by default
Cons
- Sync and some extras require a free Mozilla account
- Some sites are still optimized for Chromium first
- Smaller extension catalog than Chrome
Frequently Asked Questions
Is Firefox really free?
Yes. Firefox is completely free and open source under the MPL 2.0 license. It is developed by Mozilla, a non-profit foundation, with no paid tiers or locked features.
Is Firefox based on Chrome?
No. Firefox runs on Gecko, Mozilla's own engine, independent from Chromium, the Google-led project that powers Chrome, Edge and most other browsers.
Does Firefox sync between phone and computer?
Yes. With a free Mozilla account, bookmarks, passwords, open tabs and history sync across Windows, macOS, Linux, Android and iOS. Browsing without an account works fine too.