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Pyyan / Compare / Atlas Vector Search vs pgvector vs Milvus

Atlas Vector Search vs pgvector vs Milvus

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Vector Databases · verified 13 Aug 2026

×Atlas Vector SearchMongoDBcurrent
×pgvectorPostgreSQLcurrent
×MilvusZillizcurrent
2 slots left
SpecificationAtlas Vector SearchpgvectorMilvus
SummaryVectors beside the documents they came from.Vectors inside the database you already run.Built for billions of vectors.
IndexHNSWHNSW, IVFFlatHNSW, IVF, DiskANN, GPU
Hybrid searchYesYes, with SQLYes
HostingManagedSelf-host or any managed PostgresSelf-host and managed
LicenceProprietaryPostgreSQLApache 2.0
p50 latency~20ms~15ms~10ms
CategoryVector DatabasesVector DatabasesVector Databases
OfficialMongoDB ↗PostgreSQL ↗Zilliz ↗

Highlighted rows are where these differ.

Atlas Vector Search

  • No second datastore to keep in sync
  • Same argument as pgvector, different database

Best for teams already on MongoDB.

Full spec sheet →

pgvector

  • One database for vectors, rows and joins
  • The honest default: reach for something else only when this stops working

Best for almost everyone, until scale says otherwise.

Full spec sheet →

Milvus

  • Distributed architecture with GPU index support
  • Heavier to operate than the alternatives

Best for very large corpora.

Full spec sheet →