414 URI Too Long

What is HTTP 414?

This status code, previously known as 'Request-URI Too Long', indicates that the server is refusing to service the request because the target URI is longer than what the server is configured to handle. This is uncommon but can happen when a client converts a POST to a GET with long query parameters, when redirect loops append parameters with each cycle, or when attackers craft excessively long URLs.

Defined in RFC 9110

Common Causes

• Extremely long query strings from form data that should have been sent as POST instead of GET
• Redirect loops that keep appending query parameters with each redirect
• Client-side code generating URLs with excessive or improperly encoded data
• Malicious attempts to exploit the server with abnormally long URLs

How to Fix

• Use POST requests instead of GET when sending large amounts of data
• Check for and fix redirect loops that accumulate query parameters
• Shorten or encode URL parameters, or move complex data to the request body
• Configure the server's maximum URI length if the current limit is too restrictive for legitimate use