Zulip is an open-source team chat platform that organizes conversations into streams and topics, built for distributed teams that juggle many parallel discussions. The project is developed in the open at zulip/zulip under the Apache-2.0 license, and teams can use hosted Zulip Cloud or run the same software on their own servers.[1][2]
Quick verdict
Teams drowning in crossed chat threads get the most from Zulip: an Apache-2.0 open-source chat that files every message under a stream and topic, with a free cloud tier, self-hosting on Ubuntu, Debian, Docker, or one-click cloud images, and a Slack importer for the move. The deciding constraint is operations versus limits: self-hosting means running the server, while hosted simplicity on the free tier caps searchable history, so teams needing SAML or long retention should budget for a paid plan.[1][2][3]
Key features
Every conversation lives in a stream and a topic, so related messages stay together and catching up on one thread never means wading through unrelated chatter.[1]
Streams can be web-public, organization-wide, or private with shared history, and message threads stay visible to new subscribers, which keeps decisions discoverable.[1]
A REST API with events, outgoing webhooks, and bot framework support ships on every plan, alongside more than one hundred native integrations.[1]
Full-text search with filters and rough-draft friendly compose features, including Markdown formatting, help teams find and write messages across thousands of threads.[1]
Native apps cover web, Windows, Mac, Linux, iOS, and Android, plus a terminal client, so the same threaded conversations follow each teammate.[1]
Development happens in the public zulip/zulip repository under the Apache-2.0 license, with Python and TypeScript as its main languages.[1][2]
Who will love it
Distributed teams running many workstreams at once will feel the biggest gain, since topics let each discussion proceed without interrupting the others.[1][2]
Organizations leaving Slack for an open-source home fit well: the official importer carries history over, and the free tier keeps unlimited messages.[1][2]
IT teams that standardize login will value LDAP on every plan and SAML on paid tiers, combined with self-hosting on their own Ubuntu, Debian, or Docker infrastructure.[1][2]
Who should avoid it
Teams wanting a zero-administration chat should weigh the trade: self-hosting means running servers, updates, and backups, while the hosted free tier caps searchable history at 10,000 messages.[1][2]
Organizations that need SAML SSO or retention and compliance features must budget for Plus or Business/Enterprise tiers rather than the free offering.[1]
People who prefer a single unthreaded activity feed may find the stream-and-topic structure unfamiliar at first, since Zulip asks every message to carry a topic.[1][2]
Community and development
Inspected sample: G2 Zulip reviews page (117 verified reviews, 4.6 average) with recent 2025-2026 verified reviews read in full; no Reddit threads were inspected.
1 cited community source. Single-page G2 sample; the profile is vendor-managed with limited features. The G2 AI-generated summary was not quoted as user voice. One exact verified-reviewer quote is cited as a testimonial; no broader prevalence claim is made.
Development happens in the public zulip/zulip repository, which is not archived and carries an Apache-2.0 license, with Python and TypeScript as its main languages.[1]
The vendor states that Zulip itself runs on Zulip, and publishes essays and release announcements such as the Zulip 9.0 release notes describing current development.[1]
Alternatives and compatibility
Zulip positions itself directly against Slack: the homepage invites teams to switch with a Slack import, and the pricing page documents Slack data import, making Slack the natural hosted incumbent to compare.[1][2]
Compared with hosted chat, Zulip trades vendor-operated simplicity for control: the same codebase runs as Zulip Cloud or on team infrastructure with Docker or cloud images.[1][2]
How people experience it
Exact excerpt
Great team chat for desktop. Love the threads-within-channels UX, help keep discussions organised, feels more intuitive than Slack.
5/5 verified G2 review of Zulip praising the desktop threaded UX over Slack.
Questions worth asking
Is Zulip free to use?
Yes. The Free cloud tier includes unlimited messages, with 10,000 messages searchable and 5 GB of file storage. Paid Standard and Plus tiers raise search, storage, and retention limits.[1]
Can I self-host Zulip?
Yes. The server is Apache-2.0 licensed and the self-hosting guide documents production installation on Ubuntu or Debian, Docker images, and one-click images for DigitalOcean and Render.[1]
Can a team migrate from Slack to Zulip?
Does Zulip support SSO?
LDAP is included on every plan including Free and self-hosted. SAML SSO is available on the Plus cloud plan and self-hosted Business and Enterprise plans.[1]
Sources and editorial review
Source research. Reviewed on October 13, 2026. Written by Sanjib Sah. AI assisted; reviewed by a human editor.
We have not run or tested this product.
Inspected sample: G2 Zulip reviews page (117 verified reviews, 4.6 average) with recent 2025-2026 verified reviews read in full; no Reddit threads were inspected. Single-page G2 sample; the profile is vendor-managed with limited features. The G2 AI-generated summary was not quoted as user voice. One exact verified-reviewer quote is cited as a testimonial; no broader prevalence claim is made.
- Zulip homepage (official)
official · Observed October 13, 2026
Official homepage: organized chat for distributed teams with streams and topics, 100-plus integrations, private streams with shared history, 100% open-source with self-host or Zulip Cloud options, and a Slack team import path.
- Zulip self-hosting guide (official)
official · Observed October 13, 2026
Official self-hosting page: production installation on Ubuntu or Debian, Docker images, one-click images for DigitalOcean and Render, plus free and paid self-hosted plans.
- Zulip plans and pricing (official)
official · Observed October 13, 2026
Official pricing page: Free, Standard, and Plus cloud plans with unlimited messages and 10,000 searchable on Free; SAML on Plus; LDAP and social logins; REST API and integrations; desktop, mobile, and terminal apps; Slack data import.
- Why Zulip (official)
official · Observed October 13, 2026
Official essay on why Zulip exists: email and meetings remain essential while topic-based chat is positioned as more efficient than apps like Slack for complex processes; Zulip is used at the vendor itself.
- zulip/zulip repository (official)
official · Observed October 13, 2026
GitHub repository zulip/zulip: open-source team chat, homepage zulip.com, not archived or disabled; language statistics show Python dominant followed by TypeScript.
- zulip/zulip license (official)
official · Observed October 13, 2026
Repository LICENSE file is the Apache License 2.0 and the GitHub license API reports SPDX Apache-2.0 for zulip/zulip.
- Zulip reviews on G2 (community)
community · Observed October 13, 2026
G2 product page for Zulip showing 117 verified reviews with a 4.6 average; recent verified reviews praise topic-organized threads and open-source flexibility while noting a learning curve for newcomers and mobile app polish gaps.