Open Source Windows Chat Software

BeeBEEP is a secure (encryption based on Rijndael Algorithm, AES) peer to peer office messenger. You can talk and send files with all your colleagues inside a local area network such of an office, home or internet cafe without a server. BeeBEEP works also with VPNs. This serverless application is indispensable in all those places where privacy and security an essential requirement. For more info visit: https://www.beebeep.net

DC++ is an open source Windows client for the Direct Connect file sharing network. The DC network is a decentralized network, made up of individual servers (hubs) that users join to share files with other members on that hub. Each hub is individually run by a fellow user of the DC network, and may have certain themes to the content on the hub. Hub owners set up rules to regulate their hub as they see fit.

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.

Psi is cross-platform powerful XMPP client designed for experienced users. There are builds available for MS Windows, GNU/Linux and macOS.

Psi is a cross-platform powerful XMPP client designed for experienced users. Psi+ is a development branch of Psi XMPP client. Previously is was a sort of fork but now just consider it as a space for nightly builds.

EiskaltDC++ is a cross-platform program that uses the Direct Connect and ADC protocols. It is compatible with DC++, FlylinkDC++, LinuxDC++ and other DC clients. EiskaltDC++ also interoperates with all common DC hub software.

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.

phpFreeChat is a free, simple to install, fast and customizable chat that uses by default files for message and nickname storage. It uses AJAX to smoothly refresh and display the chat zone and the nickname zone.

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.

Jimm is an ICQ clone for mobile devices, such as celluluar phones. It is written in Java 2 Micro Edition (MIDP) and uses protocol version 8. Jimm is not affiliated with or endorsed by ICQ, Inc.

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

QChat is a simple crossplatform LAN chat. It is written using Qt4 so you can compile it on any platform supported by Qt. NOTE: you need Qt 4.3 to compile and run it.

Friendly Java IRC client, runnable either as web applet or desktop application. It is based on Eteria IRC client, with many improvements.

Deep Matrix is a Java chat-client and server system that turns 3D VRML/X3D worlds in to multi-user enviroments. The current version "Deep MatrixIP9" works on Windows, Mac, and Linux OS systems.

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.