I'm looking for a HTML or ASCII character which is a triangle pointing up or down so that I can use it as a toggle switch.
I found ↑ (
Unicode arrows heads:
For ▲ and ▼ use
▼ respectively if you cannot include Unicode characters directly (use UTF-8!).
Note that the font support for the smaller versions is not as good. Better to use the large versions in smaller font.
More Unicode arrows are at:
Lastly, these arrows are not ASCII, including ↑ and ↓: they are Unicode.