🚦 HTTP Status Code Lookup
Enter one or more HTTP status codes to see their names, meanings and class (2xx success, 4xx client error, and so on).
3 codes looked up
How the http status code lookup works
HTTP responses carry a three-digit status code whose first digit sets the class: 1xx informational, 2xx success, 3xx redirection, 4xx client error and 5xx server error. The tool pulls any three-digit codes out of what you type, so you can paste "what does 502 mean" or a list like "301 404 500", and returns each code's standard name, a plain-English description, and its class.
Covers the common standard codes from the IANA registry (RFC 9110 and related). A valid but unlisted code still gets labelled by its class. Some codes are used loosely in the wild, 401 really means "unauthenticated", and many APIs return 422 for validation errors, so also check the specific API's documentation.
Frequently asked questions
What does HTTP 404 mean?
404 Not Found means the server could not find the requested resource, usually a broken or mistyped URL, or a page that has been moved or deleted. It is a client-side (4xx) error.
What is the difference between 301 and 302?
301 Moved Permanently says the resource has a new permanent URL (and passes SEO value), while 302 Found is a temporary redirect, keep using the original URL for future requests. Use 301 for permanent moves.
What does a 500 error mean?
500 Internal Server Error is a generic server-side failure: something went wrong on the server that it cannot describe more specifically. It is not a problem with your request format, check server logs.
What do the status code classes mean?
The first digit sets the class: 1xx informational, 2xx success (200 OK, 201 Created), 3xx redirection (301, 304), 4xx client errors (400, 401, 403, 404), and 5xx server errors (500, 502, 503).
What is the difference between 401 and 403?
401 Unauthorized means you are not authenticated (no or invalid credentials), while 403 Forbidden means you are authenticated but not allowed to access the resource. 401 is "who are you?"; 403 is "you can't".
What does 204 No Content mean?
204 is a success code that says the request worked but there is deliberately no body to return, common after a DELETE or a form submission that needs no response payload. It differs from 200, which succeeds and does return a body.
When should an API return 429?
429 Too Many Requests signals rate limiting: the client has sent too many requests in a given window. A well-behaved API pairs it with a Retry-After header telling you how long to wait before trying again.
What is a 304 used for?
304 Not Modified is a caching response: the resource hasn’t changed since the version the client already holds, so the server sends no body and the client reuses its cached copy. It saves bandwidth and is triggered by conditional headers like If-None-Match.
What is the difference between 502 and 504?
Both are gateway/proxy errors. 502 Bad Gateway means the proxy reached the upstream server but got an invalid or broken response; 504 Gateway Timeout means the upstream server did not respond in time at all. 502 is "bad answer", 504 is "no answer".
What does 201 Created mean?
201 is a success code returned when a request has created a new resource, typically after a POST. The response usually includes a Location header pointing to the URL of the thing just created, which is what distinguishes it from a plain 200 OK.