Modes Overview

Modes in IRC modify the behavior of users and channels. They are set with the MODE command using + to add and - to remove.

Types of Modes

Type	Applies to	Examples
User Modes	Individual users globally	`+i`, `+o`, `+r`, `+x`
Channel Modes	Channels themselves	`+m`, `+t`, `+k`, `+i`
Channel List Modes	Channels with a list of masks	`+b`, `+e`, `+I`
Channel User Modes	Users within a specific channel	`+o`, `+v`

Quick Reference

User Modes

Mode	Name	User settable	Server set	Op only
`+B`	Bot	✅
`+g`	Caller ID	✅
`+H`	Hide Operator	✅		✅
`+i`	Invisible	✅
`+o`	IRC Operator		✅ (via OPER)
`+r`	Registered		✅ (NickServ/SASL)
`+R`	Registered Only	✅
`+s`	Server Notices	✅		✅
`+w`	Wallops	✅
`+x`	Cloaked	✅
`+Z`	Secure		✅ (TLS conn.)

Channel Modes

Mode	Name	Has argument
`+C`	No CTCP
`+c`	No Colors
`+d`	Delay Message	✅ (seconds)
`+i`	Invite Only
`+j`	Join Throttle	✅ (joins:seconds)
`+k`	Key	✅ (password)
`+l`	Limit	✅ (count)
`+m`	Moderated
`+M`	Registered Only Speak
`+n`	No External Messages
`+O`	Oper Only
`+p`	Private
`+r`	Registered
`+R`	Registered Only Join
`+s`	Secret
`+t`	Topic Lock
`+T`	No NOTICEs
`+u`	Auditorium
`+z`	Secure Only

Channel List Modes

Mode	Name	Description
`+b`	Ban	Prevents matching users from joining
`+e`	Ban Exception	Overrides +b for matching users
`+I`	Invite Exception	Allows matching users to bypass +i

Channel User Modes

Mode	Symbol	Description
`+o`	`@`	Channel operator
`+v`	`+`	Voice

Setting Modes

# User modes
MODE yournick +ix       # Set invisible and cloaked
MODE yournick -i        # Remove invisible

# Channel modes (requires channel op)
MODE #channel +mtn      # Set moderated, topic-lock, no external
MODE #channel +k secret # Set channel key
MODE #channel -m        # Remove moderated

# Channel user modes
MODE #channel +o Alice  # Give Alice channel op
MODE #channel +v Bob    # Give Bob voice
MODE #channel -o Alice  # Remove Alice's op

# List modes
MODE #channel +b *!*@bad.host.com    # Add ban
MODE #channel -b *!*@bad.host.com    # Remove ban
MODE #channel +b                     # List bans

Mode Interaction Notes

+b and +e: If a user matches both a ban (+b) and a ban exception (+e), the exception wins and they can join
+i and +I: If a channel is invite-only (+i) and a user matches an invite exception (+I), they can join without an explicit invite
+z and +Z: Channel mode +z (secure only) checks that the user has +Z (connected via TLS)
+R and +r: Channel mode +R (registered only join) requires the user has +r (registered/identified)
+O: Only IRC operators can set this mode; only IRC operators can join the channel
Removing +o from yourself removes operator-only modes +H and +s automatically