OpenSearch is an open-source (ASL 2.0) search and analytics suite used to build solutions for search, data observability, data ingestion, Security Information and Event Management (SIEM), vector databases, and more.
It's built for scalability and delivers powerful full-text search across both structured and unstructured data. Over time, OpenSearch has matured into a standalone platform with its own distinct features and capabilities.
Amazon Web Services (AWS) leads the OpenSearch initiative. The project is community-driven, with new features and innovations constantly being proposed and developed to keep pace with evolving search needs.
OpenSearch is often used for a variety of use-cases, including Log Analytics, Security Analytics, Vector Search and more.
OpenSearch Use Cases
E-Commerce Search
Online retailers use OpenSearch to power product search engines, delivering relevant results and a better shopping experience.
Enterprise Search
Large organizations build internal search engines on OpenSearch to enable fast document and knowledge retrieval across their databases.
Vector Search
OpenSearch doubles as a vector database, letting you combine traditional search, analytics, and vector search in a single system. Its vector capabilities can accelerate AI development by serving as a knowledge repository for semantic search, multimodal search, and similar applications.
Analytics and Machine Learning
OpenSearch Dashboards -- the visualization and analytics platform bundled with the project -- supports event analytics, trace analytics, and machine learning features like anomaly detection and data clustering.
Observability
OpenSearch Dashboards lets you build observability applications, schedule and distribute reports, and monitor system logs and events in real time to ensure IT health and security.
Security
OpenSearch fits naturally into SIEM solutions for investigating, detecting, analyzing, and responding to security risks that threaten enterprise operations.
What Is Amazon OpenSearch Service?
Amazon OpenSearch Service is a managed service that handles the setup, operation, and scaling of OpenSearch clusters on AWS.
An OpenSearch Service domain maps to an OpenSearch cluster -- it holds your settings, instance types, instance counts, and storage configuration. The service supports both OpenSearch and legacy Elasticsearch OSS (up to version 7.10, the last open-source release). You pick the engine when you create a domain.
Behind the scenes, it provisions all the resources your cluster needs and launches it. Failed nodes get detected and replaced automatically, cutting out the overhead of managing infrastructure yourself. Need to scale? A single API call or a few clicks in the console.
Amazon OpenSearch Service ties into CloudWatch for domain metrics and alerting, and into CloudTrail for auditing configuration API calls. Data from S3, Kinesis, and DynamoDB can be streamed directly into the service.
How Is OpenSearch Different From Elasticsearch?
OpenSearch 1.0 forked from Elasticsearch 7.10.2 with full feature parity. The two have been diverging since.
For bread-and-butter use cases -- text search, log analytics, dashboards -- the practical difference is negligible. Both get the job done.
Elasticsearch has the edge in integration breadth thanks to extensive client library support, and its active development team tends to ship bug fixes faster.
OpenSearch tends to be cheaper to run, particularly when you need advanced capabilities like a full SIEM. The equivalent features on the Elastic Stack are more mature, but that sophistication comes at a premium.
Want a deeper comparison? Read this up-to-date breakdown of OpenSearch vs. Elasticsearch.