At One Place

HTTP 414 — URI Too Long

HTTP 414
URI Too Long
The URL is longer than the server is prepared to parse.

What 414 actually means

Servers cap how long a request line can be — typically around 8 KB — and this URL exceeded it. The usual culprit is a GET request carrying data that should have been in a POST body: a search form with hundreds of parameters, a redirect loop appending to the query string each time round, or an oversized token stuffed into the URL. It is occasionally a symptom of an attempted buffer-overflow probe rather than an honest mistake.

Common causes

  • A GET request with an enormous query string, often from a form using GET instead of POST
  • A redirect loop appending parameters on every hop
  • Session data or a long token passed in the URL
  • Deeply nested filter or array parameters generated by a front-end framework
  • A malicious request probing for buffer handling bugs

If you're just trying to view the page

  1. Shorten the URL, or navigate to the page through the site's own links instead of a hand-edited address
  2. Reduce the number of filters or selections if you are on a search or report page
  3. If it happened after clicking a link, the link is malformed — tell the site owner

If it's your site

  1. Change the form method from GET to POST when it can carry a lot of data
  2. Raise `large_client_header_buffers` in Nginx or `LimitRequestLine` in Apache if a legitimate use case needs it, but treat that as a last resort
  3. Look for redirect loops that append to the query string; they grow the URL until this fires
  4. Never put session tokens in URLs — they leak through referrers, logs and browser history as well as causing this

Reference

Status code
414
Reason phrase
URI Too Long
Category
4xx — Client Error
Cacheable by default
Yes
Defined in
RFC 9110 §15.5.15

Common questions

What does HTTP 414 mean?
The URL is longer than the server is prepared to parse. Servers cap how long a request line can be — typically around 8 KB — and this URL exceeded it. The usual culprit is a GET request carrying data that should have been in a POST body: a search form with hundreds of parameters, a redirect loop appending to the query string each time round, or an oversized token stuffed into the URL.
How do I fix a 414 error?
Shorten the URL, or navigate to the page through the site's own links instead of a hand-edited address
Is 414 a client error or a server error?
414 is in the 4xx range, which means client error. The request itself was the problem, so retrying it unchanged will usually return the same code.

Related pages

Sources

  1. Hypertext Transfer Protocol (HTTP) Status Code Registry — IANA
  2. RFC 9110: HTTP Semantics — IETF

How these figures are compiled and checked