---
title: Query multiple indices or clusters with ES|QL
description: ES|QL allows you to query across multiple indices, clusters, and projects. Learn more in the following sections: Query multiple indices, Query across...
url: https://www.elastic.co/elastic/docs-builder/docs/3856/reference/query-languages/esql/esql-multi
products:
  - Elasticsearch
applies_to:
  - Elastic Cloud Serverless: Generally available
  - Elastic Stack: Generally available
---

# Query multiple indices or clusters with ES|QL
ES|QL allows you to query across multiple indices, clusters, and projects. Learn more in the following sections:
- [Query multiple indices](https://www.elastic.co/elastic/docs-builder/docs/3856/reference/query-languages/esql/esql-multi-index)
- [Query across clusters](https://www.elastic.co/elastic/docs-builder/docs/3856/reference/query-languages/esql/esql-cross-clusters)
- [Query across Serverless projects](https://www.elastic.co/elastic/docs-builder/docs/3856/reference/query-languages/esql/esql-cross-serverless-projects) <applies-to>Elastic Cloud Serverless: Preview</applies-to>
- [Query data in external storage using ES|QL Data Federation](https://www.elastic.co/elastic/docs-builder/docs/3856/reference/query-languages/esql/esql-data-federation) <applies-to>Elastic Stack: Preview since 9.5</applies-to> <applies-to>Elastic Cloud Serverless: Preview</applies-to>

To combine or reuse query results using subqueries, views, or `FORK`, refer to [Combine and reuse ES|QL queries](https://www.elastic.co/elastic/docs-builder/docs/3856/reference/query-languages/esql/esql-combine-reuse-queries).
<tip>
  For tips on writing efficient queries, refer to [Optimize ES|QL query performance](https://www.elastic.co/elastic/docs-builder/docs/3856/reference/query-languages/esql/esql-query-performance).
</tip>