HTTP Status Code Guides

The knowledge combined here comes from RFCs, mailing lists, bug reports, code repositories, Q&A forums, hard-won life experiences, and personal judgments (as opposed to copying and pasting RFCs without any value add).

Success (2xx)

These status codes indicate the request was successfully understood and accepted by the server.

Redirection (3xx)

These status codes indicate the client should take an additional step to complete the request.

Client errors (4xx)

These status codes are reserved for cases when the error is caused by the client.

Server errors (5xx)

These status codes are reserved for cases when the problem originates from the server.