4×× Client Error

414 Request-URI Too Long

The server is refusing to service the request because the request-target¹ is longer than the server is willing to interpret.

This rare condition is only likely to occur when a client has improperly converted a POST request to a GET request with long query information, when the client has descended into a "black hole" of redirection (e.g., a redirected URI prefix that points to a suffix of itself) or when the server is under attack by a client attempting to exploit potential security holes.

A 414 response is cacheable by default; i.e., unless otherwise indicated by the method definition or explicit cache controls ².

• ¹ Content Negotiation RFC7230 Section 5.3
• ² Calculating Heuristic Freshness RFC7234 Section 4.2.2]3
• Source: RFC7231 Section 6.5.12

414 Code References

.NET HTTP Status Enum HttpStatusCode.RequestUriTooLong

Rust HTTP Status Constant http::StatusCode::URI_TOO_LONG

Rails HTTP Status Symbol :request_uri_too_long

Go HTTP Status Constant http.StatusRequestURITooLong

Symfony HTTP Status Constant Response::HTTP_REQUEST_URI_TOO_LONG

Python2 HTTP Status Constant httplib.REQUEST_URI_TOO_LONG

Python3+ HTTP Status Constant http.client.REQUEST_URI_TOO_LONG

Python3.5+ HTTP Status Constant http.HTTPStatus.REQUEST_URI_TOO_LONG