Open Source Chat Software
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Chat Software
View 455 business solutionsBrowse free open source Chat software and projects 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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BeeBEEP (Free Office Messenger)
You can message and share files inside your intranet without a server.
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 -
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Fluxer
A free and open source instant messaging and VoIP platform
Fluxer is a free and open-source instant messaging and VoIP platform designed to provide communities, friend groups, and teams with a self-hostable communication alternative. The project combines real-time chat, voice calling, and community features into a unified system that can be deployed independently rather than relying on centralized proprietary services. It is built with a modern TypeScript stack and focuses on delivering a clean user experience alongside flexible infrastructure options for developers who want control over their communication environment. Fluxer supports typical messaging workflows while also aiming to provide extensibility for plugins and future integrations. Because it is open source, users can inspect, modify, and host their own instance, aligning with privacy-focused and decentralized communication trends. -
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DC++
A Windows client for the Direct Connect networks
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. -
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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. -
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ArmCord
ArmCord is a custom client designed to enhance your Discord experience
ArmCord is a custom client designed to enhance your Discord experience while keeping everything lightweight. ArmCord is built as a standalone client and doesn't rely on the original Discord client in any way. Enjoy Vencord, Shelter and their many features, or have a more vanilla experience, it's your choice! ArmCord natively supports theming of the entire app, you can easily import BetterDiscord themes and manage them. ArmCord automatically blocks all of Discord's trackers; even without any client mods, you can feel safe and secure! Unlike other clients, ArmCord supports rich presence (game activity) out of the box thanks to arRPC. ArmCord has experimental mobile support for phones running Linux such as the PinePhone. While this is still far from an ideal solution, we're slowly trying to improve it. ArmCord is using a newer build of Electron than the stock Discord app. This means you can have a much more stable and secure experience, along with slightly better performance. -
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AyuGram Desktop
Desktop Telegram client with good customization and Ghost mode.
AyuGram Desktop is a powerful, open-source Telegram desktop client designed for users who want deeper control, privacy, and customization. Built as a fork of Telegram Desktop, it extends the core experience with advanced features while staying fast and familiar. AyuGram focuses heavily on privacy tools like ghost mode and anti-recall to give users more control over their messaging behavior. The app offers extensive UI and font customization, allowing users to tailor the interface to their personal style. It also includes convenience features such as built-in translation, enhanced media previews, and streamer-friendly options. Available across Windows, macOS, and Linux, AyuGram Desktop is ideal for power users who want a more flexible Telegram experience. -
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Telegram Desktop
Telegram Desktop messaging app
Telegram Desktop is the official C++/Qt-based cross-platform client for Telegram, implementing the full Telegram API and MTProto protocol for secure messaging, voice/video calls, file sharing, and chat features. It provides message sync across devices, supports themes, stickers, bots, and is actively maintained. -
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Mattermost Desktop
Mattermost Desktop application for Windows, Mac and Linux
Mattermost Desktop is a native desktop application for Mattermost, a workplace messaging alternative to Slack. Mattermost Desktop is developed using Electron and runs on Windows, Mac and Linux. -
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DiscordBotClient
A patched version of discord, with bot login support
A patched version of Discord, with bot login support. Discord Bot Client allows you to use your bot, just like any other user account, except for Friends and Groups. -
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Psi+
Psi+ Project — development branch of Psi XMPP client
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. -
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Psi
Psi IM — Qt-based XMPP client
Psi is cross-platform powerful XMPP client designed for experienced users. There are builds available for MS Windows, GNU/Linux and macOS. -
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gSOAP Toolkit
Development toolkit for Web Services and XML data bindings for C & C++
The gSOAP toolkit is an extensive suite of portable C and C++ software to develop XML Web services with powerful type-safe XML data bindings. Easy-to-use code-generator tools allow you to directly integrate XML data in C and C++. Serializes native application data in XML. Includes WSDL/XSD schema binding and auto-coding tools, stub/skeleton compiler, Web server integration with Apache module and IIS extension, high-performance XML processing with schema validation, fast MIME/MTOM streaming, SOAP and REST Web API development, WS-* protocols (WS-Security, WS-Policy, WS-ReliableMessaging, etc), XML-RPC and JSON. Licensed under GPLv2. Visit the developer center with guides, tutorials, and examples at www.genivia.com/dev.html The documentation of the toolkit, libraries, plugins and more is available at www.genivia.com/docs.html Commercial-use licenses and expert technical support services are available at competitive pricing levels, please visit www.genivia.com/products.html -
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Abaddon
An alternative Discord client with voice support made with C++ and GTK
Alternative Discord client made in C++ with GTK. Abaddon tries its best (though is not perfect) to make Discord think it's a legitimate web client. Some of the things done to do this include: using a browser user agent, sending the same IDENTIFY message that the official web client does, using API v9 endpoints in all cases, and not using endpoints the web client does not normally use. There are still a few smaller inconsistencies, however. For example the web client sends lots of telemetry via the /science endpoint (uBlock origin stops this) as well as in the headers of all requests. Discord likes disabling accounts/forcing them to reset their passwords if they think the user is a spam bot or potentially had their account compromised. While the official client still often gets users caught in the spam filter, third party clients tend to upset the spam filter more often. If you get caught by it, you can usually appeal it and get it restored. -
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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. -
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FetLife for Android
The FetLife App on Android
This is the FetLife open source application made for Android. FetLife is the app for Kinksters who want to chat with fellow Kinksters, find out where the nearest FetLife events are happening, view other members’ profiles, and many other kinky things. With FetLife on Android, it’s easier than ever to access all the things you love about FetLife. Get notified on your Android phone so you stay on top of conversations and discussions, and discover the latest events on the app’s map. Want to be discreet? No problem, as the FetLife app comes with discreet mode so you can use the app freely without worries. -
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Miranda IM
A smaller, faster, and easier IM client
Miranda IM is an open source, multi-protocol instant messaging client designed to be very light on system resources, extremely fast and customizable. A powerful plugin-based architecture make Miranda IM one of the most flexible clients on the planet. -
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Tox
A New Kind of Instant Messaging
Tox is a peer to peer (serverless) instant messenger that focuses on security and privacy. In today's world where digital surveillance is rampant, Tox offers users a communication software alternative that's free from prying eyes and ears, and is, quite literally free and without advertising. Tox comes with all the great features you'd expect from an instant messenger application, including voice calls, video calls, file sharing and screen sharing. Everything done on Tox is encrypted using open-source libraries so you can be assured of completely private conversations. It also has no central servers that can be raided, shut down, or forced to turn over data. There are no corporate interests, no hidden agendas-- just simple, secure and easy to use messaging. -
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Ares Galaxy
A free peer-to-peer (P2P) BitTorrent file sharing client
Ares Galaxy is a free, open source BitTorrent and chat program that uses its own decentralized supernode/leaf network. Ares Galaxy has a simple, quick access interface with a built in audio/video viewer. Ares allows you to share any digital file including images, audio, video, software, documents, etc. You may now easily publish your files through the Ares’ peer-to-peer (P2P) network. As a member of the virtual community, you can search and download just about any file shared by other users. The latest versions also support the BitTorrent protocol and Shoutcast radio stations. -
19
Signal Desktop
Private messenger for Windows, Mac, and Linux
Say "hello" to a different messaging experience. An unexpected focus on privacy, combined with all of the features you expect. State-of-the-art end-to-end encryption (powered by the open source Signal Protocol) keeps your conversations secure. We can't read your messages or listen to your calls, and no one else can either. Privacy isn’t an optional mode, it’s just the way that Signal works. Every message, every call, every time. Share text, voice messages, photos, videos, GIFs and files for free. Signal uses your phone's data connection so you can avoid SMS and MMS fees. Make crystal-clear voice and video calls to people who live across town, or across the ocean, with no long-distance charges. Add a new layer of expression to your conversations with encrypted stickers. You can also create and share your own sticker packs. Group chats make it easy to stay connected to your family, friends, and coworkers. -
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Mumble
Low-latency, high quality voice chat for gamers
Mumble is an open source, low-latency, high quality voice chat software primarily intended for use while gaming. It includes game linking, so voice from other players comes from the direction of their characters, and has echo cancellation so the sound from your loudspeakers won't be audible to other players. -
21
ApexDC++
The pinnacle of file-sharing and chat - an innovative DC client!
ApexDC™ is an innovative Direct Connect client based on the DC++ and StrongDC++ projects. Direct Connect provides a rare blend of seamless file sharing and community based chat and messaging between users. ApexDC features plugins and scripting through Lua and much more. Both operators and users alike should find it a pleasant experience. Note: as of May 28th 2016 ApexDC is now primarily distributed as two separate installers one targetting 32bit and the other 64bit operating systems. Additionally XP compatible binaries are now only offered as a separate download from the files section. -
22
Dorion
Tiny alternative Discord client with a smaller footprint and support
Dorion is an alternative Discord client aimed and lower-spec or storage-sensitive PCs that supports themes, plugins, and more! Built with Rust on top of the Tauri library, Dorion uses your systems integrated Webview implementation. This means Dorion has a tiny installation size (~10mb) and works portably on Windows 11 and newer versions of Windows 10. Don't worry, you can still use it on Windows 7 too! -
23
Caprine
Elegant Facebook Messenger desktop app
Caprine is an unofficial and privacy-focused Facebook Messenger app with many useful features. Caprine is feature complete. However, we welcome contributions for improvements and bug fixes. Dark theme, Vibrant theme, privacy-focused, keyboard shortcuts, menu bar mode, work chat support, code blocks, touch bar support, and custom styles. macOS 10.10+, Linux, and Windows 7+ are supported (64-bit only). For taskbar notification badges to work on Windows 10, you'll need to enable them in Taskbar Settings. Convert your messenger to a dark theme. Ability to toggle last seen/typing indicators. Interface adapts to smaller sizes. In-house notifications to keep you up to date. Caprine is a third-party app and is not affiliated with Facebook. You can toggle dark mode in the View menu or with Command d / Control d. -
24
Signal iOS
A private messenger for iOS
Signal is a free, open source, messaging app for simple private communication with friends. Say "hello" to a different way of chatting: Signal is all about privacy, but with all the features you expect from a chat app. State-of-the-art end-to-end encryption (backed by Signal's open source protocol) keeps your chats safe. Neither we can read your messages or listen to your calls, nor anyone else. Privacy is not an optional mode, it is how Signal works. In all your messages, all your calls, forever. Send and receive messages, voice memos, photos, videos, GIFs and files for free. Signal uses your phone's data connection so no SMS or MMS charges are incurred. Make crystal clear calls and video calls to people who live across town or across the ocean with no long distance charges. Add a new layer of expression to your chats with encrypted trading cards. You can also create and share your own sticker packs. -
25
SimpleX
The first messaging platform operating without user identifiers
Other apps have user IDs: Signal, Matrix, Session, Briar, Jami, Cwtch, etc. SimpleX does not, not even random numbers. This radically improves your privacy. The video shows how you connect to your friend via their 1-time QR-code, in person or via a video link. You can also connect by sharing an invitation link. Temporary anonymous pairwise identifiers SimpleX uses temporary anonymous pairwise addresses and credentials for each user contact or group member. It allows to deliver messages without user profile identifiers, providing better meta-data privacy than alternatives. Many communication platforms are vulnerable to MITM attacks by servers or network providers. To prevent it SimpleX apps pass one-time keys out-of-band when you share an address as a link or a QR code. Double-ratchet protocol. OTR messaging with perfect forward secrecy and break-in recovery. NaCL cryptobox in each queue to prevent traffic correlation between message queues if TLS is compromised.
