IRC Definition Files

These files note interesting and useful information about IRC software. They are designed for IRC software developers, not regular IRC users.

A number of these files are based on the original lists from and are being updated and corrected to account for new software and versions.

The source code for this site is available on GitHub, under ircdocs/irc-defs. Pull requests to correct or update these lists are welcomed.
You can also talk to us at #ircdocs on Libera.Chat.

Numerics and Modes


Channel Modes

Server Modes

User Modes


Channel Member Prefixes

Channel Type Prefixes

ISUPPORT, Caps and Tags


Client Capabilities

Message Tags


Client-to-Client Protocol (CTCP) Messages

Extended Bans

Server Notice Masks

STATS Characters

self-message support

Formatting Characters