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	2,828	26,027
Forks	134	10,378
Open Issues	223	2,048
Last Commit	Oct 10, 2026	Oct 9, 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

Zulip26,027

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