GTK

GTK
Original authorsSpencer Kimball, Peter Mattis
DevelopersThe GNOME Project, eXperimental Computing Facility (XCF)
Initial releaseApril 14, 1998 (1998-04-14)
Stable release
4.22.1  / 13 March 2026 (13 March 2026)
Preview release
4.19.2 / June 27, 2025 (2025-06-27)
Written inC, CSS
Operating systemLinux and Unix-like; partial support for macOS and Windows
TypeWidget toolkit
LicenseLGPLv2.1+
Websitegtk.org
Repository

GTK (formerly GIMP ToolKit and GTK+) is a free open-source widget toolkit for creating graphical user interfaces (GUIs) targeted at Linux and specifically GNOME (though with some use in other desktop environments). It is licensed under the terms of the GNU LGPL, allowing both free and proprietary software to use it.

The GTK team releases new versions on a regular basis. GTK 4 and GTK 3 are actively maintained, while GTK 2 is no longer supported. GTK 1 is independently maintained by the CinePaint project.