head to head · open source
Rocket.Chat vs Mattermost
Rocket.Chat has 46,361 GitHub stars, 14,076 forks, 4,023 open issues and last shipped yesterday. Mattermost has 39,510 stars, 9,087 forks, 1,012 open issues and last shipped yesterday. Rocket.Chat leads on adoption by 17% (46,361 vs 39,510 stars). Rocket.Chat is written in TypeScript under a custom or non-standard licence; Mattermost is written in TypeScript under a custom or non-standard licence. Rocket.Chat has attracted 30% as many forks as stars, Mattermost 23%. Mattermost was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 2 topic tags (collaboration, hacktoberfest), so they are genuine substitutes rather than adjacent tools.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| Rocket.Chat | Mattermost | |
|---|---|---|
| GitHub stars | ★ 46K | ★ 40K |
| License | Custom / other | Custom / other |
| Written in | TypeScript | TypeScript |
| Last push | 2026-11-02 | 2026-11-02 |
| Forks | ⑂ 14K | ⑂ 9.1K |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick Rocket.Chat if
- You weight community size — 46K stars and counting
- You want the Custom / other license terms
- Your stack matches TypeScript
- You value the larger contributor base for long-term maintenance
pick Mattermost if
- You want the Mattermost feature set and don't need the biggest community
- You prefer the Custom / other license terms
- Your stack matches TypeScript
- You evaluated both and Mattermost fits your workflow better
About Rocket.Chat
The ultimate secure open source solution for team communications Rocket.Chat is an open source, secure, fully customizable communications platform developed in TypeScript for organizations with high standards of data protection. We are the ultimate solution for team communications, enabling real time conversations between colleagues, with other companies, and with your customers or citizens, regardless of how they connect with you. The result is an increase in productivity and user satisfaction rates. Every day, tens of millions of users in over 150 countries and in organizations such as Deutsche Bahn, The US…
read the full Rocket.Chat overview →
About Mattermost
Mattermost is an open core, self hosted collaboration platform that offers chat, workflow automation, voice calling, screen sharing, and AI integration. This repo is the primary source for core development on the Mattermost platform; it's written in Go and React, runs as a single Linux binary, and relies on PostgreSQL. A new compiled version is released under an MIT license every month on the 16th. Deploy Mattermost on premises, or try it for free in the cloud. Learn more about the following use cases with Mattermost: DevSecOps Incident Resolution IT Service Desk Other useful resources: Download and Install…
read the full Mattermost overview →
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Frequently asked questions
Is Rocket.Chat or Mattermost more popular?
Rocket.Chat has 46,361 GitHub stars and Mattermost has 39,510. Rocket.Chat has the larger community by that measure.
Are Rocket.Chat and Mattermost free?
Neither Rocket.Chat nor Mattermost declares a licence in this registry, so check each project's own repository before relying on either for a commercial use. Both are free to self-host.
What is the difference between Rocket.Chat and Mattermost?
Rocket.Chat is written in TypeScript and Mattermost in TypeScript. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, Rocket.Chat or Mattermost?
Choose Rocket.Chat if you want the larger community (46,361 stars) or its Custom / other licence terms. Choose Mattermost if its feature set, stack or Custom / other licence fits better. Both are self-hostable.