For each request a client sends to the server, the web server returns a 3 digit HTTP status code indicating the server's response. Eg:
HTTP/1.1 404 Not Found
Here is the list of codes that the server sends and a brief description of the code.
The status response codes are grouped as :
100 - 199 : Informational Status Codes
Provides information to the Client that the server is starting to fulfill the request.
- 100 Continue : Server says "Ready to receive the rest of the request"
- 101 Switching Protocols : "Ready to switch the protocol specified by the client, in an Upgrade Request"
200 - 299 : Client Request Successful
Status codes that indicates the client's request was successfully accepted.
- 200 OK : Successfully processed request and response is attached
- 201 Created : Created the new URI specified by the Location Header.
- 202 Accepted : Accepted for processing
- 203 Non Authoritative Info : Indicates the META information originated from another server.
- 204 No Content : Request complete, but no new information.
- 205 Reset Content : Client should reset the current document.
- 206 Partial Content : Used for GET requests for getting a part of the document. The server sends a Content-Range header to indicate the Data-Segment.
300 - 399 : Request Redirected
- 300 Multiple Choices : Requested resource contains multiple documents
- 301 Moved Permanently : The requested document has been moved from the current location, a new location is send in the Location Header
- 302 Moved Temporarily : Requested document has been temporarily moved to location specified by the location header.
- 303 See Other : The requested resource is found in a different location indicated by the Location Header.
- 304 Not Modified : Server uses this code in response to the If Modified Since Request. This indicates the document has not been modified.
- 305 Use Proxy : Client should use a proxy specified by the location header.
- 307 Temporary Redirect : Requested resource is temporarily redirected to a different location specified by the Location Header.
400 - 499 : Client Request Incomplete
Indicates the client request is incomplete and needs more information to complete the request.
- 400 Bad Request : Syntax error in the client request
- 401 Unauthorized : Request requires authentication, server sends a WWW-Authenticate Header to indicate the authentication type.
- 402 Payment Required : Reserved for Future
- 403 Forbidden : Access to request is forbidden
- 404 Not Found : Requested document is not found.(My Favorite)
- 405 Method Not Allowed : Requested method is not acceptable
- 406 Not Acceptable : Requested resource is not available in a format the client cannot accept.
- 407 Proxy Authentication Required : Unauthorized access request to a proxy server. Server sends a Proxy Authenticate header.
- 408 Request Time Out : The request timed out, client can reissue the request
- 409 Conflict : The client requests conflict with each other.
- 410 Gone : The requested resource has permanently been gone from the server
- 411 Length Required : Content-Length must be required
- 412 Precondition Failed : This is in response to one or more IF ... Headers send by the client, indicating one or more conditions specified is FALSE.
- 413 Request Entity too large : The request body is too large, server refuses to process it
- 414 Request-URI too Long : The server refuses to process the request because the URI is too large.
- 415 Unsupported Media Type : Content body is unsupported by the server.
- 416 Requested Range Not Satisfiable : Request range out of bounds.
- 417 Expectation Failed : Server failed to meet the requirements of the Expect Header Request.
500 - 599 : Server Errors
Returned when the server encounters errors.
- 500 Internal Server Error : Server config. setting or an external program has caused an error
- 501 Not Implemented : Server does not have the functionality to fulfill request
- 502 Bad Gateway : The Server encountered an invalid response from an upstream server or proxy
- 503 Service Unavailable : Service is temporarily unavailable.
- 504 Gateway Time-Out : Gateway / Proxy timed out
- 505 HTTP Version Not Supported : HTTP version used by the client is not supported
Rest of the codes are reserved for Future