HTTP Status Codes: A Quick Reference
Understand HTTP status codes from 1xx to 5xx, when they occur, and how to handle them in your applications.
HTTP status codes are 3-digit numbers returned by servers to indicate the result of a request. They're grouped into five classes.
2xx Success
200 OK — Standard success. 201 Created — Resource created (POST). 204 No Content — Success with no response body (DELETE).
3xx Redirection
301 Moved Permanently — URL changed forever. 302 Found — Temporary redirect. 304 Not Modified — Cache hit.
4xx Client Errors
400 Bad Request — Invalid input. 401 Unauthorized — Authentication required. 403 Forbidden — Authenticated but not authorized. 404 Not Found — Resource doesn't exist. 429 Too Many Requests — Rate limited.
5xx Server Errors
500 Internal Server Error — Generic server error. 502 Bad Gateway — Upstream server failed. 503 Service Unavailable — Server overloaded.