Approximate Nearest Neighbor Search Python Packages

lancedb

Developer-friendly OSS embedded retrieval library for multimodal AI. Search More; Manage Less.

pynndescent

A Python nearest neighbor descent for approximate nearest neighbors

annoy

Approximate Nearest Neighbors in C++/Python optimized for memory usage and loading/saving to disk

usearch

Fast Open-Source Search & Clustering engine × for Vectors & Arbitrary Objects × in C++, C, Python, JavaScript, Rust, Java, Objective-C, Swift, C#, GoLang, and Wolfram 🔍

libpecos

PECOS - Prediction for Enormous and Correlated Spaces

lynsedb

Embedded-first vector database that grows into a self-hosted service and lightweight cluster.

annoy-mm

Approximate Nearest Neighbors in C++/Python optimized for memory usage and loading/saving to disk

pgml

Postgres with GPUs for ML/AI apps.

scann-core

ScaNN vector similarity search as a standalone library: fast approximate nearest-neighbor search for C++, Python and Rust, no TensorFlow needed. AVX2/AVX-512 and Arm Neon/SVE kernels, free-threaded Python, optional PyTorch and TensorFlow integration. Not an official Google product.

ngt

Nearest Neighbor Search with Neighborhood Graph and Tree for High-dimensional Data

tiledb-vector-search

Cloud-native vector similarity search and storage with efficient, serverless scale-out

usearch-iscc

Fast Open-Source Search & Clustering engine × for Vectors & Arbitrary Objects × in C++, C, Python, JavaScript, Rust, Java, Objective-C, Swift, C#, GoLang, and Wolfram 🔍

annlite

⚡ A fast embedded library for approximate nearest neighbor search

lotf

[CVPR25] LotusFilter: Fast Diverse Nearest Neighbor Search

aster-vec

Embedded on-device vector database for AI agent memory and local RAG — disk-based HNSW in an LSM-tree, C++/Python, optimized for low memory footprint

lancedb-compat

Developer-friendly OSS embedded retrieval library for multimodal AI. Search More; Manage Less.

nilvec

A lightweight library for nearest neighbor search in Rust.

superkmeans

⚡ Super fast clustering for high-dimensional vectors on CPUs (x86, ARM) and GPUs — for Python and C++. Faster clustering of vector embeddings than FAISS

hannoy

Production-ready KV-backed HNSW implementation in Rust using LMDB

lorann

[NeurIPS'24] Approximate Nearest Neighbor search using reduced-rank regression, with extremely fast queries, tiny memory usage, and rapid indexing on modern vector embeddings.

instant-distance

Fast approximate nearest neighbor searching in Rust, based on HNSW index

citrusdb

(distributed) vector database

nanopq

Pure python implementation of product quantization for nearest neighbor search

kiez

🏘️ Hubness reduced nearest neighbor search for entity alignment with knowledge graph embeddings