OpenSearch
7.1/10OpenSearch is an open-source, Apache 2.0 search and analytics suite with vector search, ML connectors and AI agent APIs, used to build semantic search, RAG and observability applications.
Data last updated November 2026 · Our methodology
Overview
OpenSearch is an open-source search and analytics suite. It is made up of the OpenSearch engine, OpenSearch Dashboards for visualization, and Data Prepper for ingesting data. AWS started it in 2021 as a fork of Elasticsearch 7.10.2 and Kibana 7.10.2. Since September 2024 it has been governed by the OpenSearch Software Foundation under the Linux Foundation. In the AI area, it offers k-NN vector search and hybrid search. Its ML Commons plugin connects to external LLM and embedding models. Agentic search and agent memory APIs became generally available in version 3.3 in October 2025. Later releases added MCP client support, persistent conversation memory for agents, context management, an experimental AG-UI protocol for connecting agents to chat front ends, and an LLM-as-judge tool for testing search relevance. It suits developers, platform teams and enterprises that want a self-hosted or cloud-portable base for retrieval-augmented generation, semantic search or log analytics without vendor licence fees. There is no software price, because everything, including the security plugin, is free under Apache 2.0. Costs come from infrastructure, staff time, or a managed service such as Amazon OpenSearch Service, which connects to services like S3, Kinesis, Lambda and CloudWatch. Its main limitation is operational effort. Large clusters often need manual tuning of caches, merges and thread pools. Plugin stability can vary between versions, and Dashboards is less polished than current Kibana. It is a building block for engineers, not a ready-made AI app for business users.
Our Rating
AI Software7.1/10
Hosting & Infrastructure7.1/10
Who OpenSearch is best for
Best software for DevelopersGood fit
It is an open-source engine with REST APIs and ML Commons connectors, aimed at engineers building search and RAG applications.
Foundation governance, RBAC, audit logging, SAML and OIDC, and self-hosting all suit large organisations with platform teams.
It is widely used for log analytics and observability, covering traces, metrics and logs.
Less suited
Running and tuning clusters takes engineering skill that most small businesses do not have.
Pros & Cons
Pros
- The Apache 2.0 licence and Linux Foundation governance remove vendor licence fees and lock-in.
- Security features such as RBAC, audit logging, SAML and OIDC are free, whereas Elastic puts some of these behind paid licences.
- AI features are moving quickly: agentic search went GA in 3.3, and agent memory, MCP support and LLM-as-judge relevance testing came in later 3.x releases.
- It runs on Kubernetes, Docker, bare metal or the managed Amazon OpenSearch Service, using the same codebase.
Cons
- Large or multi-tenant clusters often need manual tuning of caches, merges and thread pools.
- Dashboards is a Kibana 7.10 fork and is described as less polished than current Kibana.
- Plugin features such as k-NN and anomaly detection can vary in stability between versions.
- Some benchmarks and Elasticsearch users report performance and feature gaps against current Elasticsearch.
Key Features
OpenSearch Pricing
Open source (self-managed)
- Vector, hybrid and agentic search
- Engine, Dashboards and Data Prepper
- Security plugin included at no cost
- You pay only for your own infrastructure
- Apache 2.0 licence with no feature gating
Frequently Asked Questions
Yes. It is licensed under Apache 2.0 with no feature gating. You pay only for infrastructure, or for a managed service if you choose one.
The OpenSearch Software Foundation under the Linux Foundation, since September 2024. AWS, SAP and Uber were premier launch members.
Yes. ML Commons provides connectors to external models. Agentic search and agent memory APIs became generally available in version 3.3, and 3.5 added persistent conversation memory and context management.
The security plugin supports Basic Auth, LDAP, SAML and OpenID Connect, along with role-based and fine-grained access control and audit logging.
Yes. Amazon OpenSearch Service is the main managed option. You can also self-host on Kubernetes, Docker or bare metal.
It stays close to Elasticsearch APIs up to version 7.10, but newer Elasticsearch features and some auth and response formats differ.
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Ranked near OpenSearch in AI Software
See OpenSearch in the listOpenSearch is #47 in AI Software by our score.
