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OpenSearch

by OpenSearch Software Foundation (Linux Foundation) · Database · also known as OpenSearch Dashboards

Apache-2.0 search and analytics suite forked from Elasticsearch and Kibana, governed by the OpenSearch Software Foundation

Apache-2.0 licenseOpen sourceFreeSelf-hostedCloudSelf-hostable
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Checked Nov 2, 2026

Overview

OpenSearch is a search and analytics suite consisting of the OpenSearch engine and OpenSearch Dashboards. It began in 2021 as a fork of Elasticsearch 7.10 and Kibana after Elastic's license change, was led by Amazon, and since 2024 is governed by the OpenSearch Software Foundation under the Linux Foundation. The entire project is Apache 2.0, including features that are commercial in the Elastic Stack such as security, alerting, anomaly detection and the k-NN vector search plugin, which supports HNSW indexes through Lucene, Faiss or NMSLIB and neural search pipelines that embed text on ingest.

Amazon OpenSearch Service is the main managed offering; other vendors and self-hosting via Docker, Helm or packages are common. Because the APIs descend from Elasticsearch 7.x, many clients and tools still work, but divergence grows with each release, so compatibility must be checked per feature. Operational characteristics (JVM, shards, heap) match its ancestor.

Capabilities

  • Full-text search and aggregations on a Lucene core
  • k-NN vector search with HNSW (Lucene, Faiss, NMSLIB engines)
  • Neural search and hybrid query pipelines
  • Security, alerting and anomaly detection plugins under Apache 2.0
  • OpenSearch Dashboards for visualization
  • Clients for Java, Python, JavaScript, Go, .NET, PHP, Ruby and Rust

Typical workflows

  1. Log analytics with Dashboards
  2. Vector and hybrid search for RAG with the k-NN plugin
  3. Drop-in alternative where Apache 2.0 licensing is required

Strengths

  • Fully Apache 2.0 including security features
  • Foundation governance
  • Managed service on AWS

Limitations

  • APIs diverge from Elasticsearch over time
  • Same JVM sizing and cluster operations burden
  • Smaller ecosystem of third-party integrations than Elastic

Prerequisites

  • JVM-based server, Docker or Kubernetes, or Amazon OpenSearch Service

Who it is for

  • Platform teams needing permissively licensed search
  • AWS users

Alternatives & comparison

  • ClickHouse

    Open-source columnar OLAP database server for fast aggregations over billions of rows, with MergeTree storage, SQL and a managed ClickHouse Cloud

    Open sourceOpen source
  • Elasticsearch

    Distributed search and analytics engine on Apache Lucene with full-text, aggregations, vector search and ES|QL; triple-licensed AGPL, SSPL and Elastic License

    MixedOpen source
  • Meilisearch

    Rust search engine for application search-as-you-type with typo tolerance, faceting and hybrid semantic search; MIT core plus BSL enterprise parts

    MixedOpen source
  • Qdrant

    Open-source vector search engine written in Rust with filterable HNSW indexes, sparse and multi-vector support, REST/gRPC APIs and a managed cloud

    Open sourceOpen source
  • Typesense

    GPL-licensed in-memory search engine in C++ offering typo-tolerant instant search, faceting, vector and hybrid search, with Typesense Cloud hosting

    Open sourceOpen source
Compare OpenSearch with its alternatives →

Sources & verification

Primary sources consulted for this record. Claims are tied to the fields each source supports; the automated link checker re-verifies every URL on a schedule.

  • License
    OpenSearch LICENSE.txt (Apache 2.0)

    https://github.com/opensearch-project/OpenSearch/blob/main/LICENSE.txt

    Supports: license_spdx, source_model

    checked Nov 1, 2026
  • Official documentation
    OpenSearch Documentation

    https://docs.opensearch.org/latest

    Supports: capabilities, languages

    checked Nov 1, 2026
  • Official site
    OpenSearch

    https://opensearch.org/

    Supports: name, summary, vendor

    checked Nov 1, 2026
  • Repository
    opensearch-project/OpenSearch

    https://github.com/opensearch-project/OpenSearch

    Supports: repo_url

    checked Nov 1, 2026
Confidence
High
Reviewed
Nov 1, 2026
Links
Broken · Nov 2, 2026

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