HTTP 200 OK vs 501 Not Implemented
HTTP 200 (OK) is a 2xx Success response, while 501 (Not Implemented) is a 5xx Server 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, 501 means that the server does not support the functionality required to fulfill the request. The server either does not recognize the request method or lacks the ability to fulfill it.
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 does not support the functionality required to fulfill the request. The server either does not recognize the request method or lacks the ability to fulfill it.
When You See It
When using an HTTP method (like PATCH) that the server doesn't support.
How to Fix
Use a different HTTP method that the server supports. Check server documentation.
Key Differences
200 is a 2xx Success response, while 501 is a 5xx Server 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 501: The server does not support the functionality required to fulfill the request. The server either does not recognize the request method or lacks the ability to fulfill it.
You encounter 200 when the most common HTTP response — indicates the request was processed successfully.
You encounter 501 when when using an HTTP method (like PATCH) that the server doesn't support.
When to Use Which
For 200 (OK): No fix needed. The request succeeded as expected. For 501 (Not Implemented): Use a different HTTP method that the server supports. Check server documentation.