Open-source alternatives to Glean

1 free, open-source alternative with 28.2K total GitHub stars.

Updated July 2026Stats synced from GitHub

Glean is a proprietary enterprise AI search platform that indexes 100+ workplace apps to power search, a conversational assistant, and autonomous agents. Pricing isn't published; buyers commonly report a per-user base license plus a separate AI add-on fee, with realistic total cost of ownership for a mid-sized deployment running into the hundreds of thousands of dollars a year once infrastructure and support fees are included.

FastGPT offers a self-hostable path to the same underlying capability — a knowledge base with retrieval-augmented search — without Glean's enterprise sales process or consumption-based credit system.

FAQ

Is there a free, open-source alternative to Glean?

Yes. FastGPT is open source (Apache-2.0) and free to self-host, without Glean's per-user licensing and FlexCredit add-ons.

What's the best open-source alternative to Glean?

FastGPT is the closest open-source match for building a searchable, RAG-powered knowledge layer, though matching Glean's 100+ prebuilt enterprise connectors will take more integration work on your end.

What are the top open-source alternatives to Glean?

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