Mozilla Firefox v157.0.1

About Mozilla Firefox

Quick answer: Mozilla Firefox is open-source software for Windows and macOS. Newest recorded version: 157.0.1. Downloads link to the official publisher.

Firefox is a web browser made by the Mozilla Foundation's subsidiary, Mozilla Corporation. It runs on Gecko, Mozilla's own rendering engine, so it is one of the few mainstream browsers that does not use Chromium or WebKit. Version 1.0 appeared in 2004, and the source code is published under the Mozilla Public License 2.0. Enhanced Tracking Protection is switched on by default and blocks known cross-site trackers, social-media trackers, cryptominers and fingerprinting scripts, with a stricter mode you can choose. A Firefox account is optional and is only needed for Sync, which carries bookmarks, passwords, history and open tabs between devices. The built-in PDF viewer, Reader View, picture-in-picture video and tab groups need no extensions, and add-ons come from addons.mozilla.org. Mozilla ships Firefox in several channels: the regular Release build, Extended Support Release (ESR) for organisations that need slower change, plus Beta, Developer Edition and Nightly for testers. Recent versions need Windows 10 or later, or macOS 10.15 or later, according to Mozilla's system-requirements page. Firefox also runs on Linux, but this site lists the Windows and macOS builds. The installer you download from mozilla.org is a small stub that fetches the rest, and an offline installer is available on the same site if you need to install on a machine without a connection. During setup you can import bookmarks and passwords from your current browser. Updates arrive automatically, and organisations that need slower change can choose the Extended Support Release instead. If you mainly want the closest match to Chrome's behaviour, a Chromium-based browser such as Brave will feel more familiar.

Key features

• ✓Gecko rendering engine, independent of Chromium and WebKit
• ✓Enhanced Tracking Protection on by default, with a stricter mode
• ✓Optional Firefox account for syncing bookmarks, passwords, history and tabs
• ✓Built-in PDF viewer, Reader View and picture-in-picture video
• ✓Container tabs (Multi-Account Containers add-on) to separate logins
• ✓Release, ESR, Beta, Developer Edition and Nightly channels
• ✓Add-on catalogue at addons.mozilla.org
• ✓Enterprise policies for managed deployments

Our review

Firefox is a good fit if you want a mainstream browser with strong default privacy settings and an engine that is not controlled by Google. It is the wrong choice if your daily work depends on web apps built mainly for Chrome, since some of them can behave differently or lose features in Firefox. Firefox also won’t suit you if you rely on Chrome-only extensions, because some of them have no Firefox equivalent, so check the Firefox add-on catalogue before switching. Telemetry is on by default and can be switched off in Settings under Privacy & Security. Make sure you download it from mozilla.org rather than a search ad.

Updated 12 Oct 2026 · Last reviewed 12 Oct 2026 · How our reviews work

Frequently asked questions about Mozilla Firefox