Rocket.Chat is an open-source communications platform for secure team messaging, channels, DMs, voice/video, integrations, and customer omnichannel support.

46k stars13.8k forkslast commit Actively maintained
Enterprise communication platform from Meta providing team chat, Groups, news feed-style posts and knowledge sharing, plus one-to-one and group video calls, live video, integrations, single sign-on and administrative controls for organizations.
Rocket.Chat is an open-source communications platform for secure team messaging, channels, DMs, voice/video, integrations, and customer omnichannel support.

46k stars13.8k forkslast commit Actively maintained
Open-source, self-hosted messaging platform for secure team collaboration with real-time chat, audio calls, screen sharing, and integrations.

38.9k stars8.9k forkslast commit Actively maintained
Open-source team chat server with topic-based threading for focused, asynchronous, and real-time communication in distributed teams.

25.8k stars10.1k forksApache-2.0last commit Actively maintained
Element is a Matrix client for secure team messaging and collaboration, offering end-to-end encrypted chats and calls with interoperability across the Matrix network.

13.4k stars2.7k forksAGPL-3.0last commit Actively maintained
Spacebar is an open source, self-hostable Discord-compatible communication platform with text chat, voice, and video, designed to work with existing clients and bots.

6.7k stars222 forksAGPL-3.0last commit Actively maintained
Synapse is a Matrix homeserver implementation for running federated, secure real-time chat and collaboration on your own infrastructure.

4.6k stars587 forksAGPL-3.0last commit Actively maintained
Tailchat is an open source team chat and collaboration platform with a strong plugin system, bot integrations, multi-group workspaces, and RBAC permissions.

3.6k stars397 forksApache-2.0last commit Actively maintained
Converse.js is an open-source, client-side web XMPP/Jabber chat app that can run standalone or be embedded into sites, with group chat and OMEMO encryption.

3.3k stars832 forksMPL-2.0last commit Actively maintained
Stoat is an open-source, self-hostable chat platform for communities and teams, offering text channels, permissions, moderation tools, and a web app.

3.3k stars383 forkslast commit Actively maintained
Stoat (formerly Revolt) is an open-source chat platform for communities and teams with channels, direct messages, roles/permissions, moderation tools, and bot support.

2.6k stars296 forksAGPL-3.0last commit Actively maintained
Self-hosted Nextcloud Talk combines chat, video calls and webinars into one secure collaboration app.

2.2k stars574 forksAGPL-3.0last commit Actively maintained
Movim is a federated social platform and web-based XMPP client for blogging, chat, communities, and real-time messaging with a responsive cross‑platform interface.

2k stars281 forksAGPL-3.0last commit Actively maintained
Self-hosted, lightweight federated messenger with end-to-end encrypted threads and optional WebRTC audio/video calling across independently hosted nodes.

1.5k stars96 forksApache-2.0last commit Actively maintained
Tracim is an open-source collaboration suite offering threaded conversations, file sharing with versioning, collaborative pages, tasks and workspace organization.

275 stars40 forkslast commit Actively maintained
SAMA is a Node.js-based open-source chat server using uWebSockets.js, MongoDB and Redis, providing WebSocket/HTTP APIs, E2EE, clustering, and web/mobile clients.

158 stars15 forksGPL-3.0last commit Actively maintained
Continuwuity is a fast, lightweight Matrix homeserver written in Rust, focused on stability, performance, and improved Matrix specification compliance for federation.

Activity unknown
WikiSuite is an integrated open source suite combining wiki/groupware, chat and conferencing, webmail, search, and infrastructure management for organizations.

Activity unknown
Prosody IM is a modern, resource-efficient XMPP (Jabber) server written in Lua, designed to be easy to configure and extend for private messaging and federation.

Activity unknown
Libervia is a modular XMPP-based communication suite offering chat, microblogging, file sharing, and other social features across web, desktop, and CLI interfaces.

Activity unknown
Every option on this page is open source and free to run on your own hardware, so you own the data and there is no subscription to cancel. 15 of 19 shipped a commit in the last six months. Licences in this list: Apache-2.0, AGPL-3.0, MPL-2.0, GPL-3.0. In exchange you take on hosting, backups and updates yourself.
Browse everything in Team Chat & Messaging.