Every common HTTP status code with what it means in plain English: 1xx information, 2xx success, 3xx redirects, 4xx problems with the request and 5xx problems on the server. Search by number or word.
| Code | Meaning |
|---|---|
200 | OK: It worked. |
301 | Moved Permanently: It’s at a new URL for good; links and search engines should update. |
302 | Found: It’s somewhere else for now. |
304 | Not Modified: Your cached copy is still good. |
400 | Bad Request: The request was malformed: bad JSON, a missing field. |
401 | Unauthorized: Not signed in: send credentials or a token. |
403 | Forbidden: Signed in, but not allowed. |
404 | Not Found: Nothing is at this URL. |
429 | Too Many Requests: Rate limited: slow down (Retry-After says how long). |
500 | Internal Server Error: Something broke on the server. |
502 | Bad Gateway: A proxy got a bad answer from the server behind it. |
503 | Service Unavailable: Down or overloaded for now; try later. |
401 means the server doesn’t know who you are (sign in, or send a valid token); 403 means it knows and you aren’t allowed. Many APIs mix them up, so read the response body too.
Both are permanent redirects. 301 lets browsers turn a POST into a GET; 308 keeps the method. For pages, 301 is the usual choice.
410 when it’s gone for good and won’t come back; search engines drop it a little faster. 404 otherwise.
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