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Alternatives to

5 Best Open Source Alternatives to Slack (2026)

Team messaging and collaboration platform

Slack starts at $7/mo — these alternatives can save you money.

#1
LLMs-from-scratch

Build ChatGPT-like LLMs from scratch with PyTorch.

Open SourceAlternative to Slack
Website GitHub
#2
prompts.chat

Community-driven ChatGPT prompts with open source and self-hosting support.

Open SourceAlternative to Slack
Website GitHub
#3
st2

Event-driven automation for DevOps and SREs with extensive integrations and ChatOps.

Open SourceAlternative to Slack
Website GitHub
#4
Peergos

Private and secure online storage with communication and productivity tools.

Open SourceAlternative to Slack
Website
#5
OpenReader WebUI

High-quality TTS document reader for multiple file formats.

Open SourceAlternative to Slack
Website

Frequently Asked Questions

What is the best free alternative to Slack?

LLMs-from-scratch is the most popular free alternative to Slack, with strong community support.

Is there an open source version of Slack?

Yes! There are 0 open source alternatives to Slack listed above.

How much does Slack cost?

Slack starts at $7/mo. The alternatives listed above include free and more affordable options.