JMM’s notes on the

Compose Key

You can see a pretty big list at


See the XCOMM Characters from "Mathematical Operators" section of the compose key list.

8 8 Infinity
: - ÷ Division sign
x x × Multiplication sign
- _ MINUS SIGN, not to be confused with “-” (HYPHEN-MINUS).
Note: This doesn’t yet work for me. This works differently depending where it’s input. Like, it works in the Firefox address bar for me (on 2023-12-11) but not in Emacs.

I can’t find ways to enter:


Some fractions are just entered with the numerator and denominator. For example, “¼” is entered using Compose 1 4. I can’t find a way to easily input a “FRACTION SLASH” (i.e. “⁄”) though.

- - . En dash
- - - Em dash
space space “ ” No-break space (non-breaking space).


Emacs has a compose key input method (called “compose”). Pretty handy along with activate-transient-input-method (C-x \) for entering accents.

Where are compose sequences defined?