Question 1

What does HTTP 411 Length Required mean?

Accepted Answer

The server refuses to accept the request without a defined Content-Length header. The client should include the content length when sending a request body.

Question 2

What causes an HTTP 411 Length Required error?

Accepted Answer

POST/PUT request missing Content-Length header. Chunked transfer encoding not supported by server. Proxy stripping the Content-Length header.

Question 3

How do I fix HTTP 411 Length Required?

Accepted Answer

Add a Content-Length header to your request Ensure your HTTP client sets Content-Length automatically Check if proxies are modifying request headers

Question 4

Is HTTP 411 a client error or server error?

Accepted Answer

411 is a Client Error response (4xx). The error is on the client side — the request contains bad syntax, refers to a missing resource, or lacks proper authentication. The server cannot or will not process the request.

Question 5

When does a server return HTTP 411?

Accepted Answer

A server returns HTTP 411 Length Required when: post/put request missing content-length header. This code belongs to the Client Error category (4xx).

HTTP 411 Length Required— What It Means, Causes & How to Fix It

Common Causes

How to Fix

Example

Related Client Error Codes

Commonly Referenced Status Codes

Related Tools