Real Compose Key on Mac OS

To get a real compose key on OS X, you need two things:

  • Bob’s excellent script to create Cocoa bindings from Compose rules
  • KeyRemap4MacBook to intercept the desired key (eg. OptRight)

I wrote a detailed article on how to set up everything together.


Based on information from the site LaC linked to I wrote a script that converts an X.org compose table to a cocoa keybindings file. Check my writeup for more information and download links.


The Cocoa text system is one way of implementing the compose key on Mac OS X. The other way is using a dedicated keyboard layout, for instance my U.S. custom keyboard layout (I haven't seen another implementation yet).

When the compose key is implemented with a keyboard layout, it will work all over the OS in any application, not just in Cocoa applications. It can be switched on and off with the UI by selecting another keyboard layout and there is a visual feedback while typing the compose combination.