Limits

This page explains various limits imposed by mIRC, however this may not be a complete list. The length is measured in bytes (equivalent to ASCII characters, includes spaces.)

Credit for this information goes to Saturn unless otherwise specified.

You can find the original limits page here.

mIRC

Name	Length	When exceeded	Description
Global limits
Line Length Limit (LLL)	949	Truncated or error	To be precise: 949 for evaluation results, 950 for command lines (excluding command prefixes.)
Variables (local or global)	949	Unset	This limit includes the variable's name. Example: using "%a" as a name loses 3 bytes (2 for the name and 1 for a space.) This means that for every extra character in the variable name, the maximum length of the value is also reduced. Note: the /set command further reduces the length limit to 946 due to the 4 characters used by "set ". (LLL) [Credit: Daveoh]
IRC server specific
Incoming lines	601	Truncated	Excludes CR/LF.
Outgoing lines	LLL	Truncated
Joined channel names	90	Parted immediately	Includes channel prefix.
Channel keys	90	Truncated
Addresses	90	Truncated	The part of the full address after the "!"; only with JOIN/QUIT messages, addresses from WHO replies are not truncated.
Nicknames	50	Truncated
Server passwords	50	Truncated	As associated with server entries
CTCPs
Incoming PING argument	24	No reply sent	First character must be a digit; leading spaces ignored.
Sockets
Socket name	90	Error
Send buffer	16384	Error	mIRC's own buffers, not WinSock's.
Receive buffer	4096	Receipt stalls	mIRC's own buffers, not WinSock's.
Socket mark	LLL		Not 512 as the helpfile says.
Hashtables
Hashtable name	90	Truncated
Hashtable size	10000	Error	In number of buckets
GUI
Editbox	LLL-1	Sent	Editbox is cleared afterwards, similar to pressing Enter.
Dialogs
Dialog name	90	Truncated
Files
Line of text	998	Split	Excluding CR/LF. Applies to all file-related commands/identifiers. [Credit: qwerty]