---
title: Middleware
description: Learn how to use Middleware to run code before a request is completed.
url: "https://nextjs.org/docs/15/pages/api-reference/file-conventions/middleware"
version: 15.5.15
lastUpdated: 2025-06-10
prerequisites:
  - "API Reference: /docs/15/pages/api-reference"
  - "File-system conventions: /docs/15/pages/api-reference/file-conventions"
---


---

For an index of all available documentation, see [/docs/15/llms.txt](/docs/15/llms.txt)