1xx Informational
100
Continue — Server received headers, client should proceed.
101
Switching Protocols — Server is switching protocols per Upgrade header.
2xx Success
200
OK — Request succeeded. Standard success response.
201
Created — Resource successfully created (POST).
204
No Content — Success, no body returned (DELETE).
206
Partial Content — Partial resource returned (range request).
3xx Redirection
301
Moved Permanently — Resource permanently moved to new URL.
302
Found — Resource temporarily moved (temp redirect).
304
Not Modified — Cached version is still valid.
307
Temporary Redirect — Temporary redirect preserving method.
308
Permanent Redirect — Permanent redirect preserving method.
4xx Client Error
400
Bad Request — Malformed request syntax or invalid data.
401
Unauthorized — Authentication required.
403
Forbidden — Server understood request but refuses it.
404
Not Found — Resource does not exist.
405
Method Not Allowed — HTTP method not supported for this endpoint.
408
Request Timeout — Server timed out waiting for request.
409
Conflict — Request conflicts with current state.
410
Gone — Resource permanently removed.
413
Payload Too Large — Request body exceeds server limit.
429
Too Many Requests — Rate limit exceeded.
5xx Server Error
500
Internal Server Error — Generic server failure.
502
Bad Gateway — Upstream server returned invalid response.
503
Service Unavailable — Server temporarily overloaded or in maintenance.
504
Gateway Timeout — Upstream server did not respond in time.