Best Open Source Chat Software 2025

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Browse free open source Chat software and projects for Windows and Mac below. Use the toggles on the left to filter open source Chat software by OS, license, language, programming language, and project status.

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1

Pidgin IM

A universal instant messaging (IM) program

See https://pidgin.im/about/ for more information. Pidgin is an instant messaging program which lets you log in to accounts on multiple chat networks simultaneously. It runs on Windows, Linux, and other UNIX operating systems. Pidgin is compatible with the following chat networks out of the box: AIM, ICQ, Google Talk, Jabber/XMPP, MSN Messenger, Yahoo!, Bonjour, Gadu-Gadu, IRC, MXit, Novell GroupWise Messenger, Lotus Sametime, SILC, SIMPLE, MySpaceIM, and Zephyr. It is written in C and makes heavy use of GLib and GTK+. Finch is a command line instant messaging program. It also lets you log in to accounts on multiple chat network simultaneously, and it is compatible with the same chat networks as Pidgin. It is written in C and makes heavy use of GLib and ncurses.

Downloads: 5,530 This Week

Last Update: 2025-09-30
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2

LAN Messenger

An intranet chat application that does not require a server.

LAN Messenger is a p2p chat application for intranet communication and does not require a server. A variety of handy features are supported including notifications, personal and group messaging with encryption, file transfer and message logging.

47 Reviews

Downloads: 331 This Week

Last Update: 2012-07-29
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3

phpMyChat

Standalone chat system developed in php, mysql and javascript

phpMyChat-Plus is an easy-to-install, easy-to-use multi-room PHP/DB chat. It is currently available for MySQLi, MariaDB, PostgreSQL, and ODBC. It supports IRC-like commands, moderators, is available in 24 languages and fully compatible with php7.

32 Reviews

Downloads: 26 This Week

Last Update: 2025-02-11
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4

Mibew Messenger 3

Mibew Messenger is an open-source live support application allowing visitors of your site to chat with your operators.

Downloads: 115 This Week

Last Update: 2023-05-30
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5

Mibew Messenger 1.x

"Mibew Messenger" - is unique software allowing visitors of your site to chat with your operators. This repo should be treated as an obsolete. For modern version of Mibew Messenger see https://sourceforge.net/projects/mibew/

21 Reviews

Downloads: 5 This Week

Last Update: 2017-08-31
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6

AJAX Chat - Open Source Web Chat

Fully customizable web chat created using AJAX.

MOVED: This project has moved to https://github.com/Frug/AJAX-Chat AJAX Chat is a fully customizable web chat implemented in JavaScript, PHP and MySQL which integrates nicely with common forum systems like phpBB, MyBB, PunBB, SMF and vBulletin. A Flash and Ruby based socket connection can be used to boost performance.

44 Reviews

Downloads: 3 This Week

Last Update: 2024-05-13
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7

Funpidgin

A fork of pidgin which aims to provide minor features that have not been addressed by the pidgin development team (including manual textbox resizing). See funpidgin.sf.net for details.

2 Reviews

Downloads: 0 This Week

Last Update: 2017-11-16
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8

MiYeok

A IRC bot program written in java.

Downloads: 0 This Week

Last Update: 2013-02-27
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9

URmIS

Downloads: 0 This Week

Last Update: 2020-11-19
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10

grochat

GroChat is a light weight web based chat software coded with PHP which doesn't need a database to work. It was developed to offer a light weight solution to people who want to install a web based chat software without having to install / customize a dat

Downloads: 0 This Week

Last Update: 2013-03-26
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11

jateon

JaTeOn is a Java Nateon Messenger clone.

Downloads: 0 This Week

Last Update: 2013-04-01
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