xkeycaps is a graphical front-end to xmodmap.  It opens a window that
looks like a keyboard; moving the mouse over a key shows what KeySyms
and Modifier bits that key generates.  Clicking on a key simulates
KeyPress/KeyRelease events on the window of your choice.  It is
possible to change the KeySyms and Modifiers generated by a key
through a mouse-based interface.  This program can also write an input
file for xmodmap to recreate your changes in future sessions.  See the
man page for more details.

Written by Jamie Zawinski.

Homepage:
https://www.jwz.org/xkeycaps/
