HTTP Response Status Code

Status codes are issued by the server in response to the client's request made to the server. It includes codes from IETF Request for Comments (RFCs).

All HTTP response status codes are divided into five classes. The first digit of the status code defines the class of response and the last two digits do not have any classification. These classes are:

1xx Informational
It means the request was received and continuing process.
2xx Successful
It means the request was successfully received and accepted.
3xx Redirection
It means further action needs to be taken to complete the request.
4xx Client Error
It means the request contains invalid syntax or cannot be completed.
5xx Server Error
It means the server failed to complete the request.

Some major HTTP status codes under each class are as follow:

1xx : Informational

Status Code	Message	Description
100	Continue	This code indicates that the initial part of the request has been received and has not yet been rejected by the server. The server intends to send the final response after the request has been fully received and acted upon.
101	Switching Protocols	This code indicates that the server switches the protocol.
102	Processing	This code indicates that the server has accepted the complete request, but has not yet completed it.

2xx : Successful

Status Code	Message	Description
200	OK	This code indicates that the request is OK.
201	Created	This code indicates that the request is complete and the new item is created.
202	Accepted	This code indicates that the request is accepted for processing but processing is not completed.
203	Non-Authoritative Information	This code indicates that the request is accepted for processing but not completed.
204	No Content	This code indicates that the server successfully processes the request but does not return any data.
205	Reset Content	This code indicates that the server successfully processed the request and asks that the requester reset its form.
206	Partial Content	This code indicates that the request is accepted for processing but not completed.

3xx : Redirection

Status Code	Message	Description
300	Multiple Choice	This code indicates that the user can select a link and go to that location.
301	Moved Permanently	This code indicates that the requested resource has been moved to a new url
302	Found	This code indicates that the requested resource has been temporarily moved to a new url
303	See Other	This code indicates that the response to the request can be found under another URL using the GET method.
304	Not Modified	This code indicates that the resource has not been modified since the version specified by the request headers If-Modified-Since or If-None-Match.
305	Use Proxy	This code indicates that the requested URL must be accessed through the proxy mentioned in the Location header.
306	Switch Proxy	This code indicates that the, it is not in use.
307	Temporary Redirect	This code indicates that the requested resource has been moved temporarily to a new URL.
308	Permanent Redirect	This code indicates that the requested resource has been moved to a new URL.

4xx : Client Error

Status Code	Message	Description
400	Bad Request	This code indicates that the server cannot process the request.
401	Unauthorized	This code indicates that the requested resource needs a username and a password.
402	Payment Required	Reserved for future use.
403	Forbidden	This code indicates that the request contained valid data and was understood by the server, but the server is refusing action due to lack of necessary permission.
404	Not Found	This code indicates that the requested resource can not be found.
405	Method Not Allowed	This code indicates that the requested method is not supported for the requested resource.
406	Not Acceptable	This code indicates that the requested resource is capable of generating only content not acceptable according to the Accept headers sent in the request.
407	Proxy Authentication Required	This code indicates that the client must first authenticate itself with the proxy.
408	Request Timeout	This code indicates that the request took longer than the server was prepared to wait.
409	Conflict	This code indicates that the request could not be completed because of a conflict.
410	Gone	This code indicates that the requested resource is no longer available.
411	Length Required	This code indicates that the "Content-Length" is not defined. The server will not accept the request without it.
412	Precondition Failed	This code indicates that the server evaluates the precondition which is given in the request and it is false.
413	Request Entity Too Large	This code indicates that the server will not accept the request, because the request entity is too large.
414	Request-URL Too Long	This code indicates that the server will not accept the request because the requested URL is too large.
415	Unsupported Media Type	This code indicates that the server will not accept the request, because the media type is not supported.
416	Requested Range Not Satisfiable	This code indicates that the client has asked for a portion of the file (byte serving), but the server cannot supply that portion.
417	Expectation Failed	This code indicates that the server cannot meet the requirements of the Expect request-header field.
421	Misdirected Request	This code indicates that the request was directed at a server which is unable to produce the response.
423	Locked	This code indicates that the server accessed a locked resource.
424	Failed Dependency	This code indicates that the request failed because it depended on another failed request.
429	Too Many Requests	This code indicates that the user has sent too many requests in a given amount of time.
431	Request Header Fields Too Large	This code indicates that the server is unable to process the request because one of the header fields is too large.

5xx : Server Error

Status Code	Message	Description
500	Internal Server Error	This code indicates that the generic error message, given when an unexpected condition was encountered.
501	Not Implemented	This code indicates that the server does not recognize the request method.
502	Bad Gateway	This code indicates that the server was acting as a proxy and received an invalid response from the upstream server.
503	Service Unavailable	This code indicates that the server is temporarily overloading or down.
504	Gateway Timeout	This code indicates that the gateway has timed out.
505	HTTP Version Not Supported	This code indicates that the server does not support "HTTP protocol".
507	Insufficient Storage	This code indicates that the server is unable to store the representation needed to complete the request.
508	Loop Detected	This code indicates that the server detected an infinite loop while processing the request.
511	Network Authentication Required	This code indicates that the client needs to authenticate to gain network access.