Front desk · HTTP Status Codes
4×× Client Error
411 Length Required
· filed 2026-07-18 · click a code to copy
HTTP 411 Length Required is a client error-class status code defined in RFC9110. A Content-Length header is required and was not provided.
Client-error responses signal that the problem is on the requesting side: the request is malformed, unauthorized, or aimed at something that isn't there. On the wire, the response begins with the status line HTTP/1.1 411 Length Required.