Comparison of IRC clients explained

The following tables compare general and technical information between a number of notable IRC client programs which have been discussed in independent, reliable prior published sources.

General

Basic general information about the notableclients: creator/company, license, etc. Clients listed on a light purple background are no longer in active development.

Client	Primary developers	Distribution model	Software license	User interface	Programming language
	Adium	Thijs Alkemade	Free software		GUI	Objective-C and C
	AmIRC	Oliver Wagner, Nicolas Sallin, Costel Mincea	Free software		GUI	?
	Bersirc^[1]	Jamie Frater, Nicholas Copeland	Free software		GUI	C (Delphi originally)
	BitchX	Colten Edwards	Free software		TUI, GUI	C
	ChatZilla	James Ross, Robert Ginda, Samuel Sieb, Gijs Kruitbosch	Free software		GUI	JavaScript, XUL
	Colloquy	Timothy Hatcher, Kiji Roshi	Free software		GUI	Objective-C
	ERC	Alexander L. Belikoff, Sergey Berezin	Free software		TUI, GUI	Emacs Lisp
	HexChat^[2]	Berke Viktor	Free software		TUI, GUI	C
	Instantbird	Florian Quèze	Free software		GUI	C++, JavaScript, CSS, XUL
	ircII	Michael Sandrof	Free software		TUI	C
	Ircle	Onno Tijdgat	Commercial, 30-day trial		GUI	C
	Irssi	Timo Sirainen	Free software		TUI	C
	KVIrc	Szymon Stefanek	Free software		GUI	C++
	Konversation	KDE	Free software		GUI	C++
	LeafChat^[3]	Samuel Marshall	Free software		GUI	Java
		Conceited Software	Commercial, 15-day trial		GUI	Objective-C
	Mibbit	Jimmy Moore	Textual Adbar		Web	JavaScript frontend, Java backend
	mIRC	Khaled Mardam-Bey	Shareware, 30-day trial^[4]		GUI	C/C++^[5]
	Nettalk	Nicolas Kruse	Free software		GUI	Visual Basic
	Pidgin		Free software		GUI	C
	PIRCH	Northwest Computer Services	Shareware		GUI	Delphi
	PJIRC	Philippe Detournay	Free software		GUI	Java
	Quassel	Manuel Nickschas, Marcus Eggenberger, Alexander von Renteln	Free software		TUI, GUI	C++
	rcirc	Ryan Yeske	Free software		TUI	Emacs Lisp
	Smuxi	Mirco Bauer	Free software		GUI, TUI, server	C#
	Snak	Kent Sorensen	Commercial		GUI	?
	Thunderbird	Mozilla Foundation	Free software		GUI	C, C++, JavaScript
	Visual IRC	Jesse McGrew	Free software		GUI	Delphi
	WeeChat	Sebastien Helleu	Free software		TUI, GUI	C
	XiRCON	Mark Hanson	Freeware		GUI	Borland C++, scripted with Tcl
Client	Primary developers	Distribution model	Software license	User interface	Programming language

Release

A brief overview of the release history.

	First public release		First stable release		Latest stable release
Client	Date	Version	Date	Version	Latest stable release
	AmIRC	1995
	Bersirc	1999
	BitchX	1996
	ChatZilla	2001
	Colloquy	2005
		2007
		1999?
	HexChat	2009-10-04	r249	2009-10-09	2.86.0
	ircII	1989	2.0.0	1989	2.0.0
	Ircle	1995
	Irssi	1999
	KVIrc	1998	0.6.0	1999-12-21	1.0.0
	Konversation	2002
	LeafChat	?	1.0
	Linkinus	2007
	Mibbit	2008				web application, no version
	mIRC	1995
	Nettalk	2004
	PIRCH	1995
	PJIRC	2002
	Quassel	2008-08-27	0.3.0
	rcirc	?	?
	Smuxi	2008-07-29	0.6	2010-09-03	0.8
	Snak	1997
	Visual IRC	1995
	WeeChat	2003
Client	Date	Version	Date	Version	Latest stable release
Client	First public release		First stable release		Latest stable release

Operating system support

The operating systems on which the clients can run natively (without emulation).

Client	Windows 7, Vista	XP, 2000	NT 4.0	NT 3.x	Me, 98	95	3.1x	ReactOS	macOS (Intel/PPC)	OS 9	OS 8	System 7 (PPC/68k)	BeOS, Haiku	OS/2, eCS, ArcaOS	AmigaOS (68k)	AmigaOS 4, MorphOS (PPC)	DOS
	AmIRC
	Bersirc
	BitchX
	ChatZilla
	Colloquy
class="table-rh"	ERC		^[6]											^[7]	^[8]			^[9]
class="table-rh"	HexChat		(2.9.5)
class="table-rh"	ircII
class="table-rh"	Ircle									^[10]
class="table-rh"	Irssi
class="table-rh"	Konversation
class="table-rh"	KVIrc								^[11]						^[12]
class="table-rh"	LeafChat
class="table-rh"	Linkinus
class="table-rh"	Mibbit
class="table-rh"	mIRC
class="table-rh"	Nettalk
class="table-rh"	PIRCH
class="table-rh"	PJIRC
class="table-rh"	Quassel
class="table-rh"	rcirc
class="table-rh"	Smuxi
class="table-rh"	Snak
class="table-rh"	Visual IRC
class="table-rh"	WeeChat
Client	Windows 7, Vista	XP, 2000	NT 4.0	NT 3.x	Me, 98	95	3.1x	ReactOS	OS X (Intel/PPC)	OS 9	OS 8	System 7 (PPC/68k)	BeOS, Haiku	OS/2, eCS	AmigaOS (68k)	AmigaOS 4, MorphOS (PPC)	DOS

Unix and Unix-like operating systems:

Unix (BSD): 386BSD, BSD/OS, FreeBSD, NetBSD, OpenBSD, SunOS, ULTRIX
Unix (System V): AIX, A/UX, HP-UX, IRIX, SCO OpenServer, Solaris, UnixWare
Unix-like: Linux, NeXTSTEP, OpenVMS, OSF/1, QNX, Tru64 UNIX

Client	386BSD	BSD/OS (BSD/386, BSDI)	FreeBSD, NetBSD, OpenBSD	SunOS	ULTRIX	AIX	A/UX	HP-UX	IRIX	SCO OpenServer	Solaris	UnixWare	Linux	NeXTSTEP	OpenVMS	OSF/1	QNX	Tru64 UNIX
	Bersirc
	BitchX
	ChatZilla
	Colloquy
	ERC
	HexChat
	ircII
	Ircle
	Irssi
	Konversation
	KVIrc
	LeafChat
	Linkinus
	Mibbit
	mIRC
	Nettalk
	PIRCH
	PJIRC
	Quassel
	rcirc
	Smuxi
	Snak
	Visual IRC
	WeeChat
Client	386BSD	BSD/OS (BSD/386, BSDI)	FreeBSD, NetBSD, OpenBSD	SunOS	ULTRIX	AIX	A/UX	HP-UX	IRIX	SCO OpenServer	Solaris	UnixWare	Linux	NeXTSTEP	OpenVMS	OSF/1	QNX	Tru64 UNIX

Protocol support

What IRC related protocols and standards are supported by each client.

Client	IPv6	SSL	TLS	DANE	OCSP	CRL	SASL	OTR
	Bersirc
	BitchX
	ChatZilla
	Colloquy								^[13]
	ERC
	HexChat
	ircII
	Ircle
	Irssi								^[14]
	Konversation
	KVIrc
	Linkinus
	Mibbit
	mIRC
	Nettalk
	PIRCH
	PJIRC
	Quassel								^[15]
	rcirc
	Smuxi								^[16]
	Snak
	Visual IRC
	WeeChat								^[17] ^[18]
Client	IPv6	SSL	TLS	DANE	OCSP	CRL	SASL	OTR

Direct Client-to-Client (DCC) support

The Direct Client-to-Client Protocol (DCC) has been the primary method of establishing connections directly between IRC clients for a long time now. Once established, DCC connections bypass the IRC network and servers, allowing for all sorts of data to be transferred between clients including files and direct chat sessions.

Client	CHAT	SEND	RESUME	TSEND	SEND T	XMIT	Passive DCC	Server	RDCC	REVERSE	RSEND	Reverse / Firewall DCC	File servers (FSERVs)	XDCC	VOICE	Whiteboard
	Bersirc
	BitchX
	ChatZilla			^[19]
	Colloquy
	ERC
	HexChat
	ircII
	Ircle
	Irssi
	Konversation
	KVIrc
	Linkinus
	Mibbit
	mIRC
	Nettalk
	PIRCH
	PJIRC
	Quassel
	rcirc
	Smuxi
	Snak
	Visual IRC
	WeeChat
Client	CHAT	SEND	RESUME	TSEND	SEND T	XMIT	Passive DCC	Server	RDCC	REVERSE	RSEND	Reverse / Firewall DCC	File servers (FSERVs)	XDCC	VOICE	Whiteboard

IRCv3 support

This software is compliant natively; other software may be compliant with extensions.^[20] ^[21]

Clients	CAP	CAP 302	Cap-notify	Account-notify	account-tag	Away-notify	batch	Bot Mode	chghost	echo-message	extended-join	Invite-notify	labeled-response	message-tags	Monitor	msgid	multi-prefix	SASL v3.1	SASL v3.2	server-time	setname	sts	userhost-in-names	UTF8ONLY	WHOX	+typing	draft/chathistory	WebIRC	draft/account-registration	draft/extended-monitor	draft/multiline	+draft/react	+draft/reply
																												?	?	?	?	?	?
																												?	?
					2.16							2.16									2.16			2.16				?	?	?	?	?	?
		Git	Git	Git		Git			Git		Git	Git		Git							Git							?	?	?	?	?	?
				Git		Git			Git		Git						Git			Git			Git					?	?	?	?	?	?
		v20.11.80+	v21.03.80+						v21.03.80+										v21.04.0+									?	?	?	?	?	?
																								?			?
		72.0+	72.0+							73.0+									72.0+	60.0+								?	?	?	?	?	?
					0.14+					0.14+ (opt in)		0.14+		0.14+						0.14+	0.14+							?	?	?	?	?	?
		2.2+							2.2+			2.2+		3.3+					3.3+		3.3+					3.3+		?	?	?	?	?	?
													7.62+								7.62+							?	?	?	?	?	?

IRCv3 SASL mechanisms

IRC SASL authentication primarily uses the same mechanisms as SASL in other protocols. Most commonly:

PLAIN as defined by RFC 4616
EXTERNAL as defined by RFC 4422
SCRAM-SHA-256 as defined by RFC 7677

Client	EXTERNAL	PLAIN	SCRAM-SHA-256

Colloquy
HexChat
Irssi
KVIrc
Konversation
Mozilla Thunderbird
WeeChat			3.2+
catgirl
mIRC			7.68+
pydle(lib.)
senpai
zIRC(lib.)

Features

Information on what features each of the clients support.

Client	Multi-server	UTF-8	Proxy server	irc:// URI scheme	Automatic updates	Scripting language
	Bersirc
	BitchX						Enhanced IrcII script
	ChatZilla						JavaScript
	Colloquy						AppleScript, Cocoa, F-Script, JavaScript, Python
	ERC				^[22]		Emacs Lisp
	HexChat						Perl, Python, Tcl, Lua, JavaScript, C, C++, and via D-Bus.
	ircII						IrcII script
	Ircle						AppleScript
	Irssi						Perl
	Konversation						Shell script, Ruby, Python, Perl, Java, C++, C#, JavaScript
	KVIrc						KVS (custom), Perl, Python, C++
	LeafChat						Java
	Linkinus						AppleScript, Cocoa
	Mibbit
	mIRC						mIRC script
	Nettalk			SOCKS			VBScript, custom
	PIRCH
	PJIRC						Partial, JavaScript
	Quassel
	rcirc						Emacs Lisp
	Smuxi						(language agnostic)
	Snak						AppleScript, IrcII script
	Visual IRC						Versus
	WeeChat						C, Perl, Python, Ruby, Lua, Tcl, Scheme (Guile)
Client		Multi-server	UTF-8	Proxy server	irc:// URI scheme	Automatic updates	Scripting language

Notes and References

http://bersirc.org/index.php/about/ Bersirc IRC Client - about Bersirc
Web site: HexChat website.
Web site: Download leafChat Free . Mac.softpedia.com . 2010-01-21 . 2012-11-18.
Web site: mIRC: Register mIRC. 2009-07-14.
Web site: mIRC: Personal FAQ . 2011-04-09.
Web site: Which versions of Windows are supported? . 19 March 2023.
Web site: Emacs 29 has been ported to the Haiku operating system. . 19 March 2023.
Web site: Emacs | eCSoft/2 . The Complete OS/2 Software Encyclopedia .
Web site: EmacsForDOS .
Requires OS X v10.4.3 or later
https://www.reactos.org/wiki/Connect_to_the_ReactOS_IRC_Channels Connect to the ReactOS IRC Channels
http://www.kvirc.net/?id=news&story=2012.07.03.03.15.1.story&dir=latest 2012-07-03: 4.2.0 Released!
Web site: Ticket 3915 requesting OTR support. 2017-03-17. 2019-10-01. https://web.archive.org/web/20191001025612/http://colloquy.info/project/ticket/3915. dead.
Web site: Irssi 1.2.0 OTR Migration Path. 2020-06-22.
Web site: Issue 1418 requesting OTR support.
Web site: Issue 651 requesting OTR support.
Web site: Cypherpunks - OTR-Enabled Software. 2014-03-16.
Web site: GitHub - weechat-otr - WeeChat script for Off-the-Record messaging. GitHub. 2014-03-16.
Web site: Mozilla ChatZilla: Bugzilla Bug 285630: chatzilla does not support resume for dcc downloads. 2009-02-20. 2009-07-14.
Web site: Clients - IRCv3 .
Web site: Libraries - IRCv3 .
Web site: irc .