1xx: Informational
Request received, continuing process.

100: Continue
101: Switching Protocols


2xx: Success
The action was successfully received, understood, and accepted.

200: OK
201: Created
202: Accepted
203: Non-Authoritative Information
204: No Content
205: Reset Content
206: Partial Content
207: Multi-Status
For use with XML-based responses when a number of actions could have been requested – details of the separate statuses are given in the message body. See WebDAV for associated specifications.


3xx: Redirection
The client must take additional action to complete the request.

300: Multiple Choices
301: Moved Permanently
302: Moved Temporarily (HTTP/1.0)
302: Found (HTTP/1.1)
see 302 Google Jacking
303: See Other (HTTP/1.1)
304: Not Modified
305: Use Proxy
Many HTTP clients (such as Mozilla and Internet Explorer) don't correctly handle responses with this status code.
306: (No longer used, but reserved. Was used for 'Switch Proxy'.)
307: Temporary Redirect


4xx: Client Error
The request contains bad syntax or cannot be fulfilled.

400: Bad Request
401: Unauthorized
Similar to 403/Forbidden, but specifically for use when authentication is possible but has failed or not yet been provided. See basic authentication scheme and digest access authentication.
402: Payment Required
The original intention was that this code might be used as part of some form of digital cash/micropayment scheme, but that has never eventuated, and thus this code has never been used.
403: Forbidden
404: Not Found
405: Method Not Allowed
406: Not Acceptable
407: Proxy Authentication Required
408: Request Timeout
409: Conflict
410: Gone
411: Length Required
412: Precondition Failed
413: Request Entity Too Large
414: Request-URI Too Long
415: Unsupported Media Type
416: Requested Range Not Satisfiable
417: Expectation Failed
449: Retry With
A Microsoft extension: The request should be retried after doing the appropriate action.


5xx: Server Error
The server failed to fulfill an apparently valid request.

500: Internal Server Error
501: Not Implemented
502: Bad Gateway
503: Service Unavailable
504: Gateway Timeout
505: HTTP Version Not Supported
509: Bandwidth Limit Exceeded
This status code, while used by many servers, is not an official HTTP status code.