XForms is a GUI toolkit based on Xlib for the X Window System.

It also includes the fdesign tool as a graphical user interface builder.

Distributed under the GNU Lesser General Public License,[1] XForms is free software.

XForms was based on the Forms Library by Mark Overmars, converted from IRIS GL (a precursor to OpenGL that also included calls to create windows and manage events) to X11.

A similar conversion was used to make the first versions of FLTK, so all these toolkits are distantly related.