loot.tools
414

URI Too Long

4xx Client Error

The requested URL is longer than the server will interpret.

414 URI Too Long means the URL itself blew past the server's limit, commonly around 8KB. The usual culprits: query strings stuffed with data that belongs in a request body, a redirect loop that appends parameters on every pass, or a GET form serializing huge inputs into the URL.

What 414 looks like on the wire

GET /search?q=aaaaaaaa...(8,000 more characters) HTTP/1.1
Host: example.com

HTTP/1.1 414 URI Too Long

About 4xx Client Error

The request has a problem the client needs to fix, like a bad URL, missing auth, or invalid input.

How to fix 414 URI Too Long

  • Move large payloads out of the query string and into a POST body.
  • Look for a redirect loop that adds parameters on each round trip.
  • If long URLs are legitimate, raise the server's limit (large_client_header_buffers in nginx).

Tools that help with 414

URL Builder & Parser
Lay out every query parameter in one view and see which ones are bloating the URL past the limit.

Where it's defined

414 URI Too Long is defined in RFC 9110 §15.5.15. MDN's 414 reference covers browser behavior and examples.

Looking for a different one? See the full HTTP status code reference.