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HTTP status codes

When a browser to access a Web page viewer's browser sends a request to the server where the web. When the browser receives and displays the front page, the server where this page will return an HTTP status code header (server header) for responding to the request contains the browser.

HTTP status codes in English for the HTTP Status Code.

Here are some common HTTP status codes:

  • 200-- request was successful
  • 301-- resources (web pages, etc.) is permanently transferred to another URL
  • 404 - resources (web pages, etc.) requested does not exist
  • 500 - Internal Server Error

HTTP status code classification

HTTP status code consists of three decimal digits, the first decimal number defines the type of status codes, the latter two figures are not classified effect. HTTP status code is divided into five types:

HTTP status code classification
classification Category Description
1** Information, the server receives the request, the requester needs to proceed
2** Successful, the operation is successfully received and processed
3 ** Redirection, further action is required to complete the request
4 ** Client error, the request contains syntax errors or not complete your request
5 ** Server error, a server error occurred during the processing of the request

HTTP status code list:

HTTP status code list
Status Code Status Code English name Chinese description
100 Continue carry on. Client should continue its request
101 Switching Protocols Switching protocols. Server switching protocol based on the client's request. Can only switch to a more advanced protocol, for example, to switch to the new version of the HTTP protocol
200 OK Request was successful. Generally used for GET and POST requests
201 Created It has been created. Successful requests and created a new resource
202 Accepted accepted. We have accepted the request, but did not complete the process
203 Non-Authoritative Information Unauthorized information. Request was successful. But not in the original meta information returned by the server, but a copy of the
204 No Content Empty. The server successfully processed, but did not return content. In the absence of updated pages to ensure the browser continues to display the current document
205 Reset Content Reset content. Server processing is successful, the user terminal (for example: a browser) should reset document view. This return code can clear your browser's form fields
206 Partial Content Part. The server successfully processed a partial GET request
300 Multiple Choices multiple choices. Resource request may include a plurality of positions, corresponding to return a list of resource characteristics and address for the user terminal (for example: a browser) Select
301 Moved Permanently Moved Permanently. The requested resource has been permanently moved to a new URI, will return information including the new URI, the browser will automatically be directed to the new URI. Any future new request should be replaced with a new URI
302 Found Temporary move. Similar to 301. But the resource only temporarily moved. The client should continue to use the original URI
303 See Other View other address. Similar to 301. Use GET and POST requests View
304 Not Modified Unmodified. The requested resource unmodified, the server returns this status code, it will not return any resources. Client typically caches visited resources by providing a header indicates that the client wish to return only after the specified date modified resource
305 Use Proxy Use a proxy. The requested resource must be accessed through a proxy
306 Unused It has been abandoned HTTP status code
307 Temporary Redirect Temporary redirect. Similar to 302. Use GET request is redirected
400 Bad Request Syntax error in client requests, the server can not understand
401 Unauthorized Request requires user authentication
402 Payment Required Reserved for future use
403 Forbidden The server understood the request to the client's request, but refused to implement this request
404 Not Found The server could not find the resources (web) at the request of the client. With this code, site designers can set "resource you have requested could not be found" personalized page
405 Method Not Allowed Client requests prohibited methods
406 Not Acceptable The server could not complete your request based on the content characteristics requested by the client
407 Proxy Authentication Required Request requires proxy authentication, similar to 401, but the requestor should use proxy authorization
408 Request Time-out The server waits for a client to send a request for too long, a timeout
409 Conflict Clashes server to complete the client's PUT request is likely to return this code when the server processes the request
410 Gone Resource requested by the client does not already exist. Unlike 410 404, if the resource has now been permanently deleted before you can use the 410 code, website designer can specify resources through a new location code 301
411 Length Required The server was unable to process the request message sent by the client without the Content-Length
412 Precondition Failed Prerequisites client requests information errors
413 Request Entity Too Large Since the request entity is too large, the server can not handle, so the request is denied. To prevent the continuous request of the client, the server may close the connection. If the server is temporarily unable to process only, it will contain information about the response of a Retry-After
414 Request-URI Too Large URI is too long request (URI typically, a URL), the server can not handle
415 Unsupported Media Type The server was unable to process the request that came with media formats
416 Requested range not satisfiable Range client request is invalid
417 Expectation Failed The server could not meet the request header Expect
500 Internal Server Error Internal server error and could not complete request
501 Not Implemented The server does not support the requested function, can not fulfill the request
502 Bad Gateway As a gateway or proxy server received from the remote server to an invalid request
503 Service Unavailable Because it is overloaded or system maintenance, the server is temporarily unable to handle the client's request. The length of the delay may be included in the Retry-After header information server
504 Gateway Time-out Acting as a gateway or proxy server, not timely access request from a remote server
505 HTTP Version not supported The server does not support the requested HTTP protocol version not finish processing