Ctrl-A: Character Info

Shows information about the character at the cursor. You get the character’s Unicode value in hex and decimal, its UTF-8 encoding, and — if its value is higher than 0xFFFF — its UTF-16 encoding. If TCC is running in Take Command, character info will be displayed in the status bar. If TCC is in a standalone console window, you’ll get a popup window.

Ctrl-A is the default hotkey for this action, but you can change it with EDITKEYS /K16:key.