Weaviate

The AI native, open-source vector database for storing data objects and vector embeddings. Bring AI-native applications to life with less hallucination, data leakage, and vendor lock-in. The core is open-source and free for self-hosting. Weaviate Cloud offers paid tiers for managed hosting, auto-scaling, and enterprise features. It natively combines vector similarity with BM25 keyword search, tunable via an alpha parameter. You can bring your own embeddings or use integrated modules for automatic vectorization with models from OpenAI, Cohere, Hugging Face, etc. Official clients exist for Python, TypeScript/JavaScript, Go, and more, plus GraphQL and REST APIs. It handles billions of vectors in production with auto-scaling in the cloud and proven case studies at large companies. Weaviate offers native hybrid search and open-source flexibility, while Pinecone focuses on fully managed, serverless pure vector search.