Slack is a messaging program designed specifically for the office, developed by Slack Technologies and now owned by Salesforce.
Zulip is an open-source team chat platform that organizes conversations around topic threads, making it easy to follow and participate in discussions. With features like threaded conversations, file sharing, and integrations with popular tools, Zulip is designed to help teams communicate more effectively.
Free tier with message history limits; paid plans from $7.25/user/month.
- Excellent search and channel organization
- Huge app ecosystem
- Reliable and fast
- Great notification controls
- Highly customizable and extensible
- Open-source and community-driven
- Threaded conversations reduce noise and increase productivity
- Wide range of integrations with popular tools
- Free plan history limit is restrictive
- Can become noisy with too many channels
- Pricing adds up for large teams
- Steep learning curve for new users
- Limited support for video conferencing
- Not suitable for very large teams or enterprises
What reviewers say
Slack Reviews
4.0 (3)Decent but has rough edges
Slack is solid overall, though it's not perfect. On the plus side, reliable and fast. That said, free plan history limit is restrictive, which held us back from rating it higher.
Solid choice
Been a daily user of Slack for a while now. Great notification controls. One minor gripe: pricing adds up for large teams, but it hasn't been a dealbreaker. Would recommend to anyone considering it.
Solid choice
Slack has quickly become part of our daily workflow. Huge app ecosystem. No major complaints so far. Would recommend to anyone considering it.
Zulip Reviews
No reviews yet.
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The Verdict
AI-generated from listing dataZulip offers a free, open‑source, thread‑focused chat ideal for small, tech‑savvy teams, while Slack provides a richer, commercial platform with broader integrations and paid scalability.
Key differences
- •Pricing model: Zulip is completely free; Slack adds cost after the limited free tier.
- •Conversation structure: Zulip uses topic threads to reduce noise; Slack relies on linear channel streams.
- •Ecosystem size: Slack has thousands of integrations and a large app directory; Zulip lists a few core integrations.
- •Support: Zulip offers community/email support only; Slack includes help‑center, email, and priority support for paid plans.
- •Enterprise readiness: Slack offers paid plans for large teams; Zulip notes it’s not suited for very large enterprises.
Pricing & value
Zulip is free; Slack’s paid plans start at $7.25 per user per month after free tier limits.
Ease of use / learning curve
Slack’s channel UI is familiar; Zulip’s threaded model has a steep learning curve for new users.
Features & depth
Slack includes audio/video huddles, workflow builder, and extensive notification controls; Zulip lacks built‑in video.
Integrations & ecosystem
Slack lists thousands of integrations via its App Directory; Zulip mentions only a few key integrations.
Collaboration
Both support file sharing, mobile apps, and basic chat; Slack adds huddles and cross‑company channels.
Scalability
Slack offers paid plans for large teams and enterprises; Zulip notes it’s not suitable for very large teams.
Support
Slack provides Help Center, email, and priority support for paid tiers; Zulip only offers email and community forum.
Choose Slack if…
Organizations needing robust integrations, paid support, and scalability for larger or cross‑company work.
Choose Zulip if…
Small, budget‑conscious, open‑source friendly teams that value threaded discussions.
Common questions
What are the ongoing costs for each platform?
Zulip is free; Slack’s free tier limits message history, and paid plans start at $7.25 per user per month.
Can I run the chat service on my own servers?
Zulip is open‑source and can be self‑hosted; Slack is a cloud‑only SaaS product.
Which tool handles large, noisy conversations better?
Zulip’s topic‑threaded model reduces noise, while Slack’s linear channels can become noisy without careful organization.