HTTP 200 OK vs 431 Request Header Fields Too Large
HTTP 200 (OK) is a 2xx Success response, while 431 (Request Header Fields Too Large) is a 4xx Client Error response. 200 indicates that the request succeeded. The meaning depends on the HTTP method: GET returns the resource, POST reports the action result, HEAD returns headers only. In contrast, 431 means that the server refuses to process the request because an individual header field or all headers collectively are too large.
Description
The request succeeded. The meaning depends on the HTTP method: GET returns the resource, POST reports the action result, HEAD returns headers only.
When You See It
The most common HTTP response — indicates the request was processed successfully.
How to Fix
No fix needed. The request succeeded as expected.
Description
The server refuses to process the request because an individual header field or all headers collectively are too large.
When You See It
When cookies accumulate to an excessive size, or a single header (like Authorization) is too long.
How to Fix
Reduce header sizes. Clear excessive cookies. Use shorter tokens.
Key Differences
200 is a 2xx Success response, while 431 is a 4xx Client Error response.
HTTP 200: The request succeeded. The meaning depends on the HTTP method: GET returns the resource, POST reports the action result, HEAD returns headers only.
HTTP 431: The server refuses to process the request because an individual header field or all headers collectively are too large.
You encounter 200 when the most common HTTP response — indicates the request was processed successfully.
You encounter 431 when when cookies accumulate to an excessive size, or a single header (like Authorization) is too long.
When to Use Which
For 200 (OK): No fix needed. The request succeeded as expected. For 431 (Request Header Fields Too Large): Reduce header sizes. Clear excessive cookies. Use shorter tokens.