List of HTTP Status Codes

HTTP status codes are three-digit numbers sent by web servers to indicate the status of a requested resource or the outcome of the request.

They provide a way for the server to communicate with the client (typically a web browser) about the success, failure, or other status of the request.

Understanding HTTP status codes can be a game-changer when you’re debugging a web application or examining server behavior.

Here’s a quick breakdown, categorized by the first digit:

1xx (Informational): These codes indicate that the request was received, and the process is continuing.
2xx (Successful): The request was received, understood, and processed successfully.
3xx (Redirection): Further action is required to complete the request. Most of these status codes suggest that the client go to another URL.
4xx (Client Errors): The request was faulty or cannot be fulfilled by the server. This is usually because of an error on the client’s part.
5xx (Server Errors): The server failed to fulfill a valid request. This means there’s a problem on the server’s side.

1xx: Informational

100 Continue: The initial part of the request has been received, and the client can continue.
101 Switching Protocols: The server is switching protocols as requested by the client.
102 Processing: Request received and understood but processing not yet completed.

2xx: Success

200 OK: All is good, the request was successful.
201 Created: New resource created, often used after a POST request.
202 Accepted: Request accepted, but not yet processed.
203 Non-Authoritative Information: Info is from a third-party server.
204 No Content: The request succeeded, but there’s no content to send back.
205 Reset Content: Similar to 204, but requires the requester to reset the document view.
206 Partial Content: The partial GET request was successful.

3xx: Redirection

300 Multiple Choices: Multiple options for the resource.
301 Moved Permanently: The URL is obsolete and moved permanently to a new address.
302 Found: Temporarily moved to a new URL. This status code indicates that the URI for the desired resource has shifted on a temporary basis. It’s worth noting that the URI may undergo additional alterations later on. Hence, for subsequent requests, the client should continue using the current URI.
303 See Other: The server is telling the client to go to a different web address to find the resource they requested. They should use a GET request to retrieve it.
304 Not Modified: Resource has not been changed; used to save bandwidth.
305 Use Proxy: Must access through a proxy.
307 Temporary Redirect: Temporarily moved, but future requests should still use the original URL.

4xx: Client Errors

400 Bad Request: The server couldn’t understand the request.
401 Unauthorized: Authentication needed, or current authentication doesn’t suffice.
402 Payment Required: Self-explanatory, right?
403 Forbidden: The server understands, but it refuses to authorize the request.
404 Not Found: You know this one! Resource not found.
405 Method Not Allowed: Request method not supported by the URL.
406 Not Acceptable: Resource can’t match request headers.
407 Proxy Authentication Required: The client must authenticate with a proxy.
408 Request Timeout: The server timed out waiting for the request.
409 Conflict: Conflicting request states.
410 Gone: Resource was there but is now gone.
411 Length Required: Missing Content-Length header.
412 Precondition Failed: One or more conditions in the request header fields failed.
413 Payload Too Large: Request body too big.
414 URI Too Long: The URL is too long.
415 Unsupported Media Type: Requested format not supported.
416 Range Not Satisfiable: Cannot serve the requested byte range.
417 Expectation Failed: Can’t meet the requirements of the Expect request header.

5xx: Server Errors

500 Internal Server Error: Something’s wrong on the server’s end.
501 Not Implemented: The server doesn’t support the functionality.
502 Bad Gateway: One server got an invalid response from another.
503 Service Unavailable: The server is down or too busy to handle the request.
504 Gateway Timeout: One server did not get a timely response from another.
505 HTTP Version Not Supported: The server doesn’t support the HTTP protocol version used.
506 Variant Also Negotiates: Content negotiation for the request results in a circular reference.
507 Insufficient Storage: The server is unable to store the representation needed to complete the request.
508 Loop Detected: WebDAV request contains an infinite loop.
510 Not Extended: Further extensions are required to fulfill the request.