# pgvector

Open-source vector similarity search extension for Postgres. pgvector is free, with no paid plan attached, at github.com.

## Facts

- **Pricing tier:** Free
- **Works on:** Self-hosted
- **Works in browser:** No

## Capabilities

- Open-source vector similarity search extension for Postgres
- HNSW and IVFFlat indexes with exact and approximate search
- Available on most managed Postgres hosts

## FAQ

### What is pgvector?

pgvector is listed under Vector Databases & RAG Infra, in the Code & Development category on Flocci AI Tools. Open-source vector similarity search extension for Postgres. It is free, with no paid plan attached, and it lives at github.com.

### Is pgvector free?

pgvector is listed as fully free — there is no paid tier attached to it in the catalog. That makes it one of the 397 entries on Flocci AI Tools with no upgrade path built in.

### Can I use pgvector in a browser, or is there an app?

pgvector needs to be installed or self-hosted — it doesn't run in a browser tab. It is available on self-hosting.

### What can pgvector do?

pgvector does 3 things the catalog singles out: Open-source vector similarity search extension for postgres; hnsw and ivfflat indexes with exact and approximate search; available on most managed postgres hosts.

### What is the best free alternative to pgvector?

Vespa is the closest free alternative: it sits in the same Vector Databases & RAG Infra sub-category and is free. LanceDB, Microsoft GraphRAG and Milvus also start free. The full list is on the alternatives page.

## Related

- [pgvector alternatives](https://aitools.flocci.in/alternatives/pgvector)
- [Vector Databases & RAG Infra](https://aitools.flocci.in/category/code-development/vector-databases-rag-infra)
- [Best free vector databases and RAG infrastructure](https://aitools.flocci.in/best/best-vector-databases-rag-infra)
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Source: Flocci AI Tools — https://aitools.flocci.in/tool/pgvector

Facts last verified: October 2026