# Best open source team chat apps > The best open source team chat app is Rocket.Chat, with 46,213 GitHub stars, the MIT license and a Docker image; Novu and Mattermost are strong alternatives. This page also breaks the picks down by team size and use: Rocket.Chat leads for startups, small business and enterprise. The overall ranking weighs GitHub stars, commits in the last year, Docker images, open-source licenses and recent commits across the 38 apps in the team chat category of the appsgit catalog. ## Key facts | Fact | Value | |---|---| | Question | What is the best open source team chat app? | | Picks | 20 | | Top pick | Rocket.Chat (46,213 stars) | | Data as of | Oct 7, 2026 | | Canonical URL | https://appsgit.com/best/open-source-team-chat | ## Top picks 10 of the 38 apps in the team chat category, ranked on GitHub stars, commits in the last year, Docker images, open-source licenses and recent commits. - [Rocket.Chat](https://appsgit.com/apps/rocket-chat) (46,213 stars, MIT, TypeScript, Docker): Rocket.Chat has 46,213 GitHub stars, uses the MIT license, ships a Docker image and had 2,155 commits in the last year; it replaces Slack and Discord. - [Novu](https://appsgit.com/apps/novu) (40,118 stars, MIT, TypeScript, Docker): Novu has 40,118 GitHub stars, uses the MIT license, ships a Docker image and had 2,234 commits in the last year; it replaces Twilio SendGrid. - [Mattermost](https://appsgit.com/apps/mattermost) (39,271 stars, AGPL-3.0, TypeScript, Docker): Mattermost has 39,271 GitHub stars, uses the AGPL-3.0 license, ships a Docker image and had 1,913 commits in the last year; it replaces Slack. - [Chatwoot](https://appsgit.com/apps/chatwoot) (37,569 stars, MIT, Ruby, Docker): Chatwoot has 37,569 GitHub stars, uses the MIT license, ships a Docker image and had 1,379 commits in the last year; it replaces Zendesk and Intercom. - [ntfy](https://appsgit.com/apps/ntfy) (34,644 stars, Apache-2.0, Go, Docker): ntfy has 34,644 GitHub stars, uses the Apache-2.0 license, ships a Docker image and had 832 commits in the last year. - [OpenWA](https://appsgit.com/apps/openwa) (15,071 stars, MIT, TypeScript, Docker): OpenWA has 15,071 GitHub stars, uses the MIT license, ships a Docker image and had 3,139 commits in the last year. - [Zulip](https://appsgit.com/apps/zulip) (25,998 stars, Apache-2.0, Python): Zulip has 25,998 GitHub stars, uses the Apache-2.0 license and had 4,853 commits in the last year; it replaces Slack and Discord. - [Apprise](https://appsgit.com/apps/apprise) (17,531 stars, BSD-2-Clause, Python, Docker): Apprise has 17,531 GitHub stars, uses the BSD-2-Clause license, ships a Docker image and had 231 commits in the last year. - [Fluxer](https://appsgit.com/apps/fluxer) (10,488 stars, AGPL-3.0, TypeScript, Docker): Fluxer has 10,488 GitHub stars, uses the AGPL-3.0 license, ships a Docker image and had 1,394 commits in the last year; it replaces Discord. - [Gotify](https://appsgit.com/apps/gotify) (16,036 stars, MIT, Go, Docker): Gotify has 16,036 GitHub stars, uses the MIT license, ships a Docker image and had 247 commits in the last year. ## Best for startups Ranked for startups on GitHub stars, commits in the last year, Docker images, open-source licenses, project websites and recent commits. - [Rocket.Chat](https://appsgit.com/apps/rocket-chat) (46,213 stars, MIT, TypeScript, Docker): Rocket.Chat has 46,213 GitHub stars, uses the MIT license, ships a Docker image and had 2,155 commits in the last year; it replaces Slack and Discord. For startups it also scores on a Docker image, a permissive license (MIT), a project website and a commit in the last 90 days. - [Novu](https://appsgit.com/apps/novu) (40,118 stars, MIT, TypeScript, Docker): Novu has 40,118 GitHub stars, uses the MIT license, ships a Docker image and had 2,234 commits in the last year; it replaces Twilio SendGrid. For startups it also scores on a Docker image, a permissive license (MIT), a project website and a commit in the last 90 days. - [Chatwoot](https://appsgit.com/apps/chatwoot) (37,569 stars, MIT, Ruby, Docker): Chatwoot has 37,569 GitHub stars, uses the MIT license, ships a Docker image and had 1,379 commits in the last year; it replaces Zendesk and Intercom. For startups it also scores on a Docker image, a permissive license (MIT), a project website and a commit in the last 90 days. - [ntfy](https://appsgit.com/apps/ntfy) (34,644 stars, Apache-2.0, Go, Docker): ntfy has 34,644 GitHub stars, uses the Apache-2.0 license, ships a Docker image and had 832 commits in the last year. For startups it also scores on a Docker image, a permissive license (Apache-2.0), a project website and a commit in the last 90 days. - [Mattermost](https://appsgit.com/apps/mattermost) (39,271 stars, AGPL-3.0, TypeScript, Docker): Mattermost has 39,271 GitHub stars, uses the AGPL-3.0 license, ships a Docker image and had 1,913 commits in the last year; it replaces Slack. For startups it also scores on a Docker image, an open-source license, a project website and a commit in the last 90 days. ## Best for small business and enterprise Ranked for small business and enterprise (the same order for each) on GitHub stars, commits in the last year, open-source licenses and recent commits. - [Rocket.Chat](https://appsgit.com/apps/rocket-chat) (46,213 stars, MIT, TypeScript, Docker): Rocket.Chat has 46,213 GitHub stars, uses the MIT license, ships a Docker image and had 2,155 commits in the last year; it replaces Slack and Discord. For small business it also scores on a Docker image, an open-source license, a project website and a commit in the last 90 days. - [Novu](https://appsgit.com/apps/novu) (40,118 stars, MIT, TypeScript, Docker): Novu has 40,118 GitHub stars, uses the MIT license, ships a Docker image and had 2,234 commits in the last year; it replaces Twilio SendGrid. For small business it also scores on a Docker image, an open-source license, a project website and a commit in the last 90 days. - [Mattermost](https://appsgit.com/apps/mattermost) (39,271 stars, AGPL-3.0, TypeScript, Docker): Mattermost has 39,271 GitHub stars, uses the AGPL-3.0 license, ships a Docker image and had 1,913 commits in the last year; it replaces Slack. For small business it also scores on a Docker image, an open-source license, a project website and a commit in the last 90 days. - [Chatwoot](https://appsgit.com/apps/chatwoot) (37,569 stars, MIT, Ruby, Docker): Chatwoot has 37,569 GitHub stars, uses the MIT license, ships a Docker image and had 1,379 commits in the last year; it replaces Zendesk and Intercom. For small business it also scores on a Docker image, an open-source license, a project website and a commit in the last 90 days. - [ntfy](https://appsgit.com/apps/ntfy) (34,644 stars, Apache-2.0, Go, Docker): ntfy has 34,644 GitHub stars, uses the Apache-2.0 license, ships a Docker image and had 832 commits in the last year. For small business it also scores on a Docker image, an open-source license, a project website and a commit in the last 90 days. ## How this list was made - Candidates: the 38 apps in the team chat category. Archived projects and projects with no commit in the last two years are left out. - Base score: GitHub stars on a log scale plus commits in the last 12 months (log scale, capped at 1,000). - Bonus points for a published Docker image, an OSI-approved open-source license and a commit in the last 90 days. - Each "Best for" section re-ranks the same apps with that audience's profile (for example startups add points for permissive licenses, project websites and recent commits; small business for Docker images and deploy guides). - Source-available apps can rank, but they are labelled and never described as open source. ## FAQ ### Is Rocket.Chat free? Yes. Rocket.Chat is open-source software released under the MIT license, so you can self-host it at no cost. You only pay for the server it runs on, and some projects also offer an optional paid cloud plan. ### Which open source team chat app is best for a startup? Rocket.Chat ranks first for startups, with 46,213 GitHub stars, the MIT license and a Docker image; Novu and Chatwoot follow. The startups ranking adds points for Docker images, permissive licenses, project websites and recent commits on top of stars and activity. ### Which open source team chat app is best for a small business? Rocket.Chat ranks first for small business, with 46,213 GitHub stars, the MIT license and a Docker image; Novu and Mattermost follow. The small business ranking adds points for Docker images, open-source licenses, project websites, recent commits and deploy guides on top of stars and activity. ### Can I self-host these team chat apps with Docker? Yes, 9 of the 10 picks. Rocket.Chat, Novu and Mattermost publish Docker images, so you can run them on a VPS or home server with Docker Compose. The others install from their own packages or source; follow each project's install guide. ### Are all of these team chat apps open source? All 10 apps on this list are open source. You can self-host and modify each one under its license. ## Related questions - [What is the best open source budgeting app?](https://appsgit.com/best/open-source-budgeting-software) - [What is the best open source CMS?](https://appsgit.com/best/open-source-cms) - [What is the best open source file sharing app?](https://appsgit.com/best/open-source-file-sharing) - [What is the best open source analytics tool?](https://appsgit.com/best/open-source-analytics) - [What is the best open source developer tool?](https://appsgit.com/best/open-source-developer-tools) - [What is the best open source time tracking tool?](https://appsgit.com/best/open-source-time-tracking) - [What is the best open source workflow automation tool?](https://appsgit.com/best/open-source-workflow-automation) - [What is the best open source SSO and identity provider?](https://appsgit.com/best/open-source-identity-providers) ## See also - [All team chat apps](https://appsgit.com/categories/team-chat) - [All utilities apps](https://appsgit.com/categories/utilities) - [All finance & budgeting apps](https://appsgit.com/categories/finance-budgeting) - [Open-source alternatives to Slack](https://appsgit.com/alternatives/slack) - [Open-source alternatives to Discord](https://appsgit.com/alternatives/discord) - [Open-source alternatives to Twilio SendGrid](https://appsgit.com/alternatives/sendgrid) - [Open-source alternatives to Zendesk](https://appsgit.com/alternatives/zendesk) - [Open-source alternatives to Intercom](https://appsgit.com/alternatives/intercom) - [Open-source alternatives to Freshdesk](https://appsgit.com/alternatives/freshdesk) - [Mattermost vs Rocket.Chat](https://appsgit.com/compare/mattermost-vs-rocket-chat) - [Rocket.Chat vs Zulip](https://appsgit.com/compare/rocket-chat-vs-zulip) - [Mattermost vs Zulip](https://appsgit.com/compare/mattermost-vs-zulip) - [Chatwoot vs Zammad](https://appsgit.com/compare/chatwoot-vs-zammad) --- Canonical page: https://appsgit.com/best/open-source-team-chat Source: appsgit (https://appsgit.com), the app store for github. Data from the GitHub API, refreshed nightly. Machine access: JSON API https://appsgit.com/api/v1/apps (OpenAPI: https://appsgit.com/openapi.json), MCP server https://mcp.appsgit.com/mcp, full index https://appsgit.com/llms-full.txt.