Element vs Mattermost

Comparing two open source alternatives to Discord and Slack . Use the comparison below to decide which one fits your needs.

Element

AGPL-3.0

Open-source Matrix client for secure, decentralized messaging, voice, and video — runs on your own server.

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Mattermost

Mattermost is an open source platform for secure collaboration across the entire software development lifecycle..

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Side-by-side comparison

	Element	Mattermost
License	AGPL-3.0	—
Self-hostable	Yes	No
GitHub Stars	13,398	38,878
Forks	2,735	8,927
Open Issues	3,833	967
Last Commit	Aug 21, 2026	Aug 22, 2026
First Released	Jul 22, 2015	Jun 15, 2015
Categories	Team Chat & Messaging Tools	Team Chat & Messaging Tools
Tags	#chat #messaging #privacy #self hosted #voice chat	—

GitHub stars over time

Element

Mattermost38,878

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