HTTP 1.1 Status code and what it means

The following table shows the common HTTP 1.1 status codes along with their corresponding state information and meanings.

You should be cautious about using state codes that only have HTTP 1.1 support, because many browsers can only support HTTP 1.0. If you use HTTP 1.1-specific status codes, it's a good idea to check the HTTP version number of the request.

Status code	Status information	Meaning
100	Continue	The initial request has been accepted and the customer should continue to send the remainder of the request. (HTTP 1.1 new)
101	Switching protocols	The server converts the request to a different protocol (HTTP 1.1 new)
200	Ok	Everything is fine, and the answer document for Get and post requests follows.
201	Created	The server has created the document, and the location header gives its URL.
202	Accepted	The request has been accepted, but processing has not been completed.
203	Non-authoritative Information	The document has returned normally, but some of the answer headers may be incorrect because a copy of the document is being used (HTTP 1.1 is new).
204	No Content	The browser should continue to display the original document without a new document. This status code is useful if the user periodically refreshes the page and the servlet can determine that the user's document is new enough.
205	Reset Content	There is no new content, but the browser should reset what it displays. Used to force the browser to clear form input (HTTP 1.1 new).
206	Partial Content	The customer sent a GET request with a range header, and the server completed it (HTTP 1.1 new).
300	Multiple choices	The documents requested by the client can be found in multiple locations, which are already listed in the returned document. If the server wants to make a preference, it should be indicated in the location answer header.
301	Moved Permanently	The client requests a document elsewhere, the new URL is given in the location header, and the browser should automatically access the new URL.
60W	Found	Similar to 301, but the new URL should be considered temporary instead of permanent. Note that the corresponding state information in the HTTP1.0 is "moved temporatily". When this status code appears, the browser can automatically access the new URL, so it is a useful status code. Note that this status code can sometimes be replaced with 301. For example, if the browser incorrectly requests Http://host/~user (a trailing slash is missing), some servers return 301, and some return 302. Strictly speaking, we can only assume that the browser will automatically redirect only if the original request is get. Please see 307.
303	Other	Similar to 301/302, the difference is that if the original request was post,location headers the redirected target document specified should be fetched via get (HTTP 1.1 new).
304	Not Modified	The client has a buffered document and makes a conditional request (typically providing a if-modified-since header that indicates that the customer wants to update only a document that is newer than the specified date). The server tells the customer that the previously buffered document can continue to be used.
305	Use Proxy	The document requested by the customer should be extracted via the proxy server indicated by the location header (HTTP 1.1 new).
307	Temporary Redirect	Same as 302 (Found). Many browsers incorrectly respond to 302 responses for redirection, even if the original request is post, even if it is actually only redirected when the POST request is answered at 303. For this reason, HTTP 1.1 has been added 307 to further clear the locale code: when a 303 reply occurs, the browser can follow the redirected get and post requests, and if 307 answers, the browser can only follow the redirection of the got request. (HTTP 1.1 new)
400	Bad Request	A syntax error occurred on the request.
401	Unauthorized	The customer attempted to access a password-protected page without authorization. A www-authenticate header is included in the answer, the browser displays the user name/password dialog Accordingly, and then makes the request again after filling in the appropriate authorization header.
403	Forbidden	The resource is not available. The server understands the customer's request, but refuses to process it. This is usually caused by a permission setting on a file or directory on the server.
404	Not Found	The resource at the specified location could not be found. This is also a common answer.
405	Method Not allowed	The request method (get, POST, head, DELETE, put, Trace, and so on) does not apply to the specified resource. (HTTP 1.1 new)
50W	Not acceptable	The specified resource has been found, but its MIME type is incompatible with the customer specified in the Accpet header (HTTP 1.1 new).
407	Proxy Authentication Required	Similar to 401 indicates that the customer must first be authorized by the proxy server. (HTTP 1.1 new)
408	Request Timeout	The customer has not made any requests during the wait time that the server has allowed. Customers can repeat the same request at a later time. (HTTP 1.1 new)
409	Conflict	Usually associated with put requests. The request cannot succeed because the request and the current state of the resource are conflicting. (HTTP 1.1 new)
410	Gone	The requested document is no longer available and the server does not know which address should be redirected to. It differs from 404 in that the return of 407 indicates that the document left the specified location permanently, while 404 indicates that the document is not available because of an unknown reason. (HTTP 1.1 new)
411	Length Required	The server cannot process the request unless the customer sends a content-length header. (HTTP 1.1 new)
412	Precondition Failed	Some prerequisites specified in the request header failed (HTTP 1.1 new).
413	Request Entity Too Large	The size of the target document exceeds the size that the server is currently willing to handle. If the server considers itself able to process the request later, it should provide a Retry-after header (HTTP 1.1 new).
414	Request URI Too Long	URI is too long (HTTP 1.1 new).
416	Requested Range not satisfiable	The server does not meet the range header specified by the customer in the request. (HTTP 1.1 new)
500	Internal Server Error	The server encountered an unexpected situation and could not complete the customer's request.
501	Not implemented	The server does not support the functionality required to implement the request. For example, the customer issued a put request that the server does not support.
502	Bad Gateway	When the server acts as a gateway or proxy, it accesses the next server in order to complete the request, but the server returns an illegal answer.
503	Service unavailable	The server failed to answer due to maintenance or overload. For example, a servlet might return 503 if the database connection pool is full. The server can provide a retry-after header when it returns 503.
504	Gateway Timeout	Used by a server acting as a proxy or gateway, indicating that an answer cannot be received from a remote server in a timely manner. (HTTP 1.1 new)
505	HTTP Version not supported	The server does not support the HTTP version specified in the request. (HTTP 1.1 new)