GNU IceCat

GNU IceCat
GNU IceCat
	GNU IceCat new-tab page
Developers	GNUzilla team, GNU Project
Stable release	140.4.0 / 14 October 2025
Engine	Gecko;
Operating system	Linux; Windows; macOS; Android;
Type	Web browser
License	MPL-2.0 (source files from Mozilla Firefox browser); GPL-3.0-or-later (Scripts to convert Firefox into IceCat);
Website	www.gnu.org/software/gnuzilla/
Repository	git.savannah.gnu.org/cgit/gnuzilla.git ;

GNU IceCat, formerly known as GNU IceWeasel, is a completely free version of the Mozilla Firefox web browser distributed by the GNU Project. Its official releases were compatible with Linux, Windows, Android and macOS. Currently, official releases of IceCat are being distributed only through GNU Guix.

IceCat is released as a part of GNUzilla, GNU's rebranding of a code base that used to be the Mozilla Application Suite. As an internet suite, GNUzilla also includes a mail and newsgroup program, and an HTML composer.

Mozilla produces free and open-source software, but the binaries include trademarked artwork. The GNU Project attempts to keep IceCat in synchronization with upstream development of Firefox ESR (long-term support versions) while removing all trademarked artwork and non-free add-ons. It also maintains a large list of free software plugins. In addition, it includes several security and privacy features not found in the mainline Firefox browser.