pgvector

pgvector is an extension that adds vector storage and similarity search to PostgreSQL. It is not a separate database server and not a standalone product: it is installed into an existing PostgreSQL database, which must already be running, so embeddings can be stored and queried alongside ordinary relational data. It is developed by the pgvector open-source project and is licensed under the PostgreSQL License, an open-source licence. The GitHub repository was created in 2021. The latest release is v0.8.7, published on 1 October 2026, and the version number shows the extension is still on a 0.x line. It is free to use, and there is no commercial edition. It is run as a self-managed PostgreSQL extension, and whether a particular managed PostgreSQL service offers it has not been checked here, so anyone who relies on a managed service should confirm availability with their provider before planning around it. pgvector suits teams that already use PostgreSQL and want vector search without adding a second database to operate. Because it depends on PostgreSQL, it should be listed and evaluated as an extension of that database rather than as an independent engine.