411
Length Required
4xx Client error
Class
RFC 9110 §15.5.12
Defined in
What does HTTP 411 mean?
The server requires a Content-Length header. Some servers refuse request bodies sent with chunked transfer encoding or without a length — common with old proxies and certain upload endpoints.
4xx Client error: The request has a problem the client can fix: wrong URL, missing credentials, bad data or too many requests.
How to fix 411 Length Required
- Send
Content-Lengthwith the request body.
411 and SEO
Not relevant for crawling.
Example response
HTTP/1.1 411 Length RequiredRelated status codes
- 400 Bad Request — The server cannot process the request because it is malformed.
- 413 Content Too Large — The request body is larger than the server allows.
Check which status code a URL returns with the HTTP header checker.
All HTTP status codesSearch the full list of status codes from 100 to 599 with their meanings and SEO impact.
Open the full list Frequently asked questions
What does status code 411 mean?
411 Length Required: The server requires a
Content-Length header.How do I fix a 411 error?
Send
Content-Length with the request body.Does 411 affect SEO?
Not relevant for crawling.