Hangouts
Free
Hangouts is an instant messaging software developed by Google.
Jitsi
Open Source
Jitsi (formerly SIP Communicator) is a free and open source multiplatform voice (VoIP), videoconferencing and instant messaging application.
Samepage
Freemium
Wire
Free
Wire is a cross-platform, encrypted instant messaging client created by Wire Swiss. It is available for iOS, Android, Linux, Windows, macOS and Web browser cl…
Rocket.Chat
Open Source
Rocket.Chat free open source chat solution.
Matrix.org
Open Source
Matrix is an open protocol for real-time communication. It is designed to allow users with accounts at one communications service provider to communicate with…
Priority Matrix
Commercial
Priority Matrix is a time management software application that is supported on a number of platforms, including Microsoft Windows, Mac OS X, Android, and iOS.…
Grape
Commercial
Grape is an REST-like API framework for Ruby. It's designed to run on Rack or complement existing web application frameworks such as Rails and Sinatra by prov…
Zulip
Open Source
Zulip is a chat and collaborative software.
Wickr
Free
Wickr is an instant messenger application.
Hubgets
Commercial
Hubgets provides chat, voice and video turning team communication.
Discord
Free
Discord is a freeware proprietary VoIP application designed for gaming communities.
Glip
Freemium
Glip is fully searchable, real-time group chat; video chat, task management, file sharing app.
Mattermost
Open Source
Mattermost is an open source, private cloud Slack-alternative, Workplace messaging for web, PCs and phones. MIT-licensed.
Ora
Commercial
Ora is a real-time all-in-one workspace for teams.
eXo Platform
Commercial
eXo Platform is an open source, standard-based, Enterprise Social Collaboration Platform.
TribeScale
Free
TribeScale is an All-in-One platform to coordinate your team around what really matters - communication, goals, decisions, tasks and results.
Flock
Freemium
Flock is a communication app for teams. Packed with tons of productivity features, Flock drives efficiency and boosts speed of execution.
Fleep
Freemium
Fleep enables communication within and across organizations, be it your team chats, project communication or 1:1 conversations.
Dialog Messenger
Free Personal
Dialog Messenger is a handy and feature-rich enterprise multi-device messenger available for server or cloud.
Gitter
Freemium
Gitter is an open source instant messaging and chat room system for developers and users of GitHub repositories.
Compare Slack with alternatives
Compare Priority Matrix and Slack and decide which is most suitable for you.
Compare Dialog Messenger and Slack and decide which is most suitable for you.