Every time a browser or a program asks a web server for something, the server replies with
a three-digit status code that says what happened. The first digit sets the class, from
2xx for success to 4xx for a problem with the request and
5xx for a problem on the server. Here is the full list in plain English,
with detail pages for the codes worth knowing well.
Check a real URL →
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Or test any status code, live
This site will return any status code you ask for, from the edge. Point a client at
/status/<code> to test error handling, retries and redirects. Free to
use, no key, CORS-open. Add ?sleep=2000 to delay the response by up to
five seconds; 429 and 503 include a Retry-After header; 3xx codes include
a real Location.
$ curl -i https://computerscience.co.uk/status/418
HTTP/2 418
{"code":418,"message":"I'm a Teapot","docs":"…"}
1xx Informational
Informational: the request was received and the process is continuing.
100
Continue
The client should continue with its request.
101
Switching Protocols
The server is switching protocols as requested.
103
Early Hints
Preliminary headers sent while the response is prepared.
2xx Success
Success: the request was received, understood and accepted.
200
OK
The request succeeded. The most common status code.
201
Created
The request succeeded and a new resource was created.
202
Accepted
The request was accepted but not yet processed.
204
No Content
Success, but there is no body to return.
206
Partial Content
Part of the resource is returned, used for range requests.
3xx Redirection
Redirection: further action is needed to complete the request.