Chatto vs Zulip

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

Chatto

AGPL-3.0

A self-hosted chat application for teams and communities with video calls, voice calls, and screen sharing.

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Zulip

Apache-2.0

Open-source team chat with a unique topic-based threading model that makes it easy to follow multiple conversations.

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Side-by-side comparison

	Chatto	Zulip
License	AGPL-3.0	Apache-2.0
Self-hostable	Yes	Yes
GitHub Stars	2,822	25,999
Forks	133	10,356
Open Issues	219	2,044
Last Commit	Oct 6, 2026	Oct 6, 2026
First Released	Apr 8, 2026	Sep 25, 2015
Categories	Team Chat & Messaging Tools	Team Chat & Messaging Tools
Tags	#chat #collaboration #self hosted #privacy	#chat #messaging #collaboration

GitHub stars over time

Chatto

Zulip25,999

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