What is the difference between Pumble and Zulip?

Pumble is best for Teams wanting a free Slack alternative, while Zulip is best for Open-source communities and teams wanting threaded messaging. Pumble starts at Free and Zulip starts at Free.

Is Pumble or Zulip cheaper?

Pumble starts at Free and is free. Zulip starts at Free and is free.

Is there a free alternative to Zulip?

Both Pumble and Zulip offer free tiers.

Pumble vs Zulip

Pumble is free team messaging app with unlimited message history, channels, and 1-on-1 video calls, while Zulip is open-source team chat with a unique topic-based threading model for organized conversations. Zulip is open source and can be self-hosted, giving you full control over your data. Pumble is built for teams wanting a free slack alternative, whereas Zulip targets open-source communities and teams wanting threaded messaging.

At a glance

	Pumble	Zulip
Best for	Teams wanting a free Slack alternative	Open-source communities and teams wanting threaded messaging
Starting price	Free	Free
Free tier	✓	✓
Open source	—	✓
Free tier available	✓	✓
Open source	—	✓
Channels	✓	—
Markdown	—	✓
Open Source	—	✓
Self-Hosted	—	✓
Threads	✓	—
Topic Threading	—	✓
Unlimited History	✓	—
Video Calls	✓	—

Pumble

Strengths

Unlimited message history on every plan — nothing gets lost or archived
Organizes conversations into channels so discussions stay focused and searchable
The core product is free with no paywalled essentials
Includes video calls alongside the core feature set — fewer separate tools needed

Weaknesses

May lack some advanced features
Some advanced features require upgrading to a paid plan
Fewer built-in features means you may need additional tools to cover gaps
Notification overload is a real problem as the number of channels grows

Try Pumble → Full review

Zulip

Strengths

Open source and transparent
Topic-based threading keeps conversations organized by subject, not just time
Fully open-source — you can self-host, audit the code, and avoid vendor lock-in
The core product is free with no paywalled essentials

Weaknesses

May lack some advanced features
Self-hosting is free but requires server maintenance and DevOps knowledge
Self-hosting requires Linux admin skills and ongoing server maintenance
Notification overload is a real problem as the number of channels grows

Try Zulip → Full review

The bottom line

Pricing: Both Pumble and Zulip are free, so this decision comes down to features and philosophy rather than budget.

Feature gaps: Pumble offers Channels, Threads and Unlimited History that Zulip lacks. Zulip brings Markdown, Open Source and Self-Hosted that Pumble does not have.

Team fit: Pumble is geared toward small teams teams, while Zulip is aimed at any size teams. Pick the one that matches where your team is today and where it is headed — migrating tools later is always painful.

Open source: Zulip is open source, meaning you can self-host, audit the code, and avoid vendor lock-in. Pumble is proprietary — you are trusting the vendor with your data and uptime.

Where each tool shines: Pumble's biggest strengths are: unlimited message history on every plan — nothing gets lost or archived. organizes conversations into channels so discussions stay focused and searchable. Zulip's biggest strengths are: open source and transparent. topic-based threading keeps conversations organized by subject, not just time.

Watch out for: With Pumble, users commonly note that may lack some advanced features. With Zulip, the main complaint is that may lack some advanced features.

Choose Pumble if...

Your profile matches its sweet spot: teams wanting a free slack alternative
You specifically need Channels and Threads
You care about organizes conversations into channels so discussions stay focused and searchable
Your team size fits the small teams profile Pumble is designed for

Choose Zulip if...

You need a tool built for open-source communities and teams wanting threaded messaging
You need self-hosting, data sovereignty, or the ability to audit source code
You specifically need Markdown and Open Source
You care about topic-based threading keeps conversations organized by subject, not just time
Your team size fits the any size profile Zulip is designed for