HTTP Status Codes

HTTP defines these standard status codes that can be used to convey the results of a client’s request. The status codes are divided into five categories.

1xx: Informational – Communicates transfer protocol-level information.

2xx: Success – Indicates that the client’s request was accepted successfully.

3xx: Redirection – Indicates that the client must take some additional action in order to complete their request.

4xx: Client Error – This category of error status codes points the finger at clients.

5xx: Server Error – The server takes responsibility for these error status codes.

1xx Status Codes [Informational]

Status Code	Description
100 Continue	An interim response. Indicates to the client that the initial part of the request has been received and has not yet been rejected by the server. The client SHOULD continue by sending the remainder of the request or, if the request has already been completed, ignore this response. The server MUST send a final response after the request has been completed.
101 Switching Protocol	Sent in response to an Upgrade request header from the client, and indicates the protocol the server is switching to.
102 Processing (WebDAV)	Indicates that the server has received and is processing the request, but no response is available yet.
103 Early Hints	Primarily intended to be used with the Link header. It suggests the user agent start preloading the resources while the server prepares a final response.

2xx Status Codes [Success]

Status Code	Description
200 OK	Indicates that the request has succeeded.
201 Created	Indicates that the request has succeeded and a new resource has been created as a result.
202 Accepted	Indicates that the request has been received but not completed yet. It is typically used in log running requests and batch processing.
203 Non-Authoritative Information	Indicates that the returned metainformation in the entity-header is not the definitive set as available from the origin server, but is gathered from a local or a third-party copy. The set presented MAY be a subset or superset of the original version.
204 No Content	The server has fulfilled the request but does not need to return a response body. The server may return the updated meta information.
205 Reset Content	Indicates the client to reset the document which sent this request.
206 Partial Content	It is used when the Range header is sent from the client to request only part of a resource.
207 Multi-Status (WebDAV)	An indicator to a client that multiple operations happened, and that the status for each operation can be found in the body of the response.
208 Already Reported (WebDAV)	Allows a client to tell the server that the same resource (with the same binding) was mentioned earlier. It never appears as a true HTTP response code in the status line, and only appears in bodies.
226 IM Used	The server has fulfilled a GET request for the resource, and the response is a representation of the result of one or more instance-manipulations applied to the current instance.

3xx Status Codes [Redirection]

Status Code	Description
300 Multiple Choices	The request has more than one possible response. The user-agent or user should choose one of them.
301 Moved Permanently	The URL of the requested resource has been changed permanently. The new URL is given by the Location header field in the response. This response is cacheable unless indicated otherwise.
302 Found	The URL of the requested resource has been changed temporarily. The new URL is given by the Location field in the response. This response is only cacheable if indicated by a Cache-Control or Expires header field.
303 See Other	The response can be found under a different URI and SHOULD be retrieved using a GET method on that resource.
304 Not Modified	Indicates the client that the response has not been modified, so the client can continue to use the same cached version of the response.
305 Use Proxy (Deprecated)	Indicates that a requested response must be accessed by a proxy.
306 (Unused)	It is a reserved status code and is not used anymore.
307 Temporary Redirect	Indicates the client to get the requested resource at another URI with same method that was used in the prior request. It is similar to 302 Found with one exception that the same HTTP method will be used that was used in the prior request.
308 Permanent Redirect (experimental)	Indicates that the resource is now permanently located at another URI, specified by the Location header. It is similar to 301 Moved Permanently with one exception that the same HTTP method will be used that was used in the prior request.

4xx Status Codes (Client Error)

Status Code	Description
400 Bad Request	The request could not be understood by the server due to incorrect syntax. The client SHOULD NOT repeat the request without modifications.
401 Unauthorized	Indicates that the request requires user authentication information. The client MAY repeat the request with a suitable Authorization header field
402 Payment Required (Experimental)	Reserved for future use. It is aimed for using in the digital payment systems.
403 Forbidden	Unauthorized request. The client does not have access rights to the content. Unlike 401, the client’s identity is known to the server.
404 Not Found	The server can not find the requested resource.
405 Method Not Allowed	The request HTTP method is known by the server but has been disabled and cannot be used for that resource.
406 Not Acceptable	The server doesn’t find any content that conforms to the criteria given by the user agent in the Accept header sent in the request.
407 Proxy Authentication Required	Indicates that the client must first authenticate itself with the proxy.
408 Request Timeout	Indicates that the server did not receive a complete request from the client within the server’s allotted timeout period.
409 Conflict	The request could not be completed due to a conflict with the current state of the resource.
410 Gone	The requested resource is no longer available at the server.
411 Length Required	The server refuses to accept the request without a defined Content- Length. The client MAY repeat the request if it adds a valid Content-Length header field.
412 Precondition Failed	The client has indicated preconditions in its headers which the server does not meet.
413 Request Entity Too Large	Request entity is larger than limits defined by server.
414 Request-URI Too Long	The URI requested by the client is longer than the server can interpret.
415 Unsupported Media Type	The media-type in Content-type of the request is not supported by the server.
416 Requested Range Not Satisfiable	The range specified by the Range header field in the request can’t be fulfilled.
417 Expectation Failed	The expectation indicated by the Expect request header field can’t be met by the server.
418 I’m a teapot (RFC 2324)	It was defined as April’s lool joke and is not expected to be implemented by actual HTTP servers. (RFC 2324)
420 Enhance Your Calm (Twitter)	Returned by the Twitter Search and Trends API when the client is being rate limited.
422 Unprocessable Entity (WebDAV)	The server understands the content type and syntax of the request entity, but still server is unable to process the request for some reason.
423 Locked (WebDAV)	The resource that is being accessed is locked.
424 Failed Dependency (WebDAV)	The request failed due to failure of a previous request.
425 Too Early (WebDAV)	Indicates that the server is unwilling to risk processing a request that might be replayed.
426 Upgrade Required	The server refuses to perform the request. The server will process the request after the client upgrades to a different protocol.
428 Precondition Required	The origin server requires the request to be conditional.
429 Too Many Requests	The user has sent too many requests in a given amount of time (“rate limiting”).
431 Request Header Fields Too Large	The server is unwilling to process the request because its header fields are too large.
444 No Response (Nginx)	The Nginx server returns no information to the client and closes the connection.
449 Retry With (Microsoft)	The request should be retried after performing the appropriate action.
450 Blocked by Windows Parental Controls (Microsoft)	Windows Parental Controls are turned on and are blocking access to the given webpage.
451 Unavailable For Legal Reasons	The user-agent requested a resource that cannot legally be provided.
499 Client Closed Request (Nginx)	The connection is closed by the client while HTTP server is processing its request, making the server unable to send the HTTP header back.

5xx Status Codes (Server Error)

Status Code	Description
500 Internal Server Error	The server encountered an unexpected condition that prevented it from fulfilling the request.
501 Not Implemented	The HTTP method is not supported by the server and cannot be handled.
502 Bad Gateway	The server got an invalid response while working as a gateway to get the response needed to handle the request.
503 Service Unavailable	The server is not ready to handle the request.
504 Gateway Timeout	The server is acting as a gateway and cannot get a response in time for a request.
505 HTTP Version Not Supported (Experimental)	The HTTP version used in the request is not supported by the server.
506 Variant Also Negotiates (Experimental)	Indicates that the server has an internal configuration error: the chosen variant resource is configured to engage in transparent content negotiation itself, and is therefore not a proper endpoint in the negotiation process.
507 Insufficient Storage (WebDAV)	The method could not be performed on the resource because the server is unable to store the representation needed to successfully complete the request.
508 Loop Detected (WebDAV)	The server detected an infinite loop while processing the request.
510 Not Extended	Further extensions to the request are required for the server to fulfill it.
511 Network Authentication Required	Indicates that the client needs to authenticate to gain network access.

6. REST Specific HTTP Status Codes

4xx: Client Error – This category of error status codes points the finger at clients.

5xx: Server Error – The server takes responsibility for these error status codes.