The following is a list of
HyperText Transfer ProtocolHypertext Transfer Protocol is an application-level protocol for distributed, collaborative, hypermedia information systems. Its use for retrieving inter-linked resources, called hypertext documents, led to the establishment of the World Wide Web in 1990 by English physicist Tim Berners-Lee...
(HTTP) response status codes. This includes codes from IETF
internet standardIn computer network engineering, an Internet Standard is a normative specification of a technology or methodology applicable to the Internet. Internet Standards are created and published by the Internet Engineering Task Force .-Overview:...
s as well as unstandardised
RFCsIn computer network engineering, a Request for Comments is a memorandum published by the Internet Engineering Task Force describing methods, behaviors, research, or innovations applicable to the working of the Internet and Internet-connected systems.Through the Internet Society, engineers and...
, other specifications and some additional commonly used codes. The first digit of the status code specifies one of five classes of response; the bare minimum for an HTTP client is that it recognises these five classes. Microsoft
IISInternet Information Services - formerly called Internet Information Server - is a set of Internet-based services for servers created by Microsoft for use with Microsoft Windows. It is the world's second most popular web server in terms of overall websites behind the industry leader Apache HTTP...
may use additional decimal sub-codes to provide more specific information, but these are not listed here.
The following is a list of
HyperText Transfer ProtocolHypertext Transfer Protocol is an application-level protocol for distributed, collaborative, hypermedia information systems. Its use for retrieving inter-linked resources, called hypertext documents, led to the establishment of the World Wide Web in 1990 by English physicist Tim Berners-Lee...
(HTTP) response status codes. This includes codes from IETF
internet standardIn computer network engineering, an Internet Standard is a normative specification of a technology or methodology applicable to the Internet. Internet Standards are created and published by the Internet Engineering Task Force .-Overview:...
s as well as unstandardised
RFCsIn computer network engineering, a Request for Comments is a memorandum published by the Internet Engineering Task Force describing methods, behaviors, research, or innovations applicable to the working of the Internet and Internet-connected systems.Through the Internet Society, engineers and...
, other specifications and some additional commonly used codes. The first digit of the status code specifies one of five classes of response; the bare minimum for an HTTP client is that it recognises these five classes. Microsoft
IISInternet Information Services - formerly called Internet Information Server - is a set of Internet-based services for servers created by Microsoft for use with Microsoft Windows. It is the world's second most popular web server in terms of overall websites behind the industry leader Apache HTTP...
may use additional decimal sub-codes to provide more specific information, but these are not listed here. The phrases used are the standard examples, but any human-readable alternative can be provided. Unless otherwise stated, the status code is part of the HTTP/1.1 standard.
1xx Informational
Request received, continuing process.
This class of status code indicates a provisional response, consisting only of the Status-Line and optional headers, and is terminated by an empty line. Since HTTP/1.0 did not define any 1xx status codes, servers
must not send a 1xx response to an HTTP/1.0 client except under experimental conditions.
100 Continue
- This means that the server has received the request headers, and that the client should proceed to send the request body (in the case of a request for which a body needs to be sent; for example, a POST request). If the request body is large, sending it to a server when a request has already been rejected based upon inappropriate headers is inefficient. To have a server check if the request could be accepted based on the request's headers alone, a client must send
Expect: 100-continue as a header in its initial request (see Expect header) and check if a 100 Continue status code is received in response before continuing (or receive 417 Expectation Failed and not continue).
101 Switching Protocols
- This means the requester has asked the server to switch protocols and the server is acknowledging that it will do so.
102 Processing (
WebDAVWeb-based Distributed Authoring and Versioning, or WebDAV, is a set of extensions to the Hypertext Transfer Protocol that allows computer-users to edit and manage files collaboratively on remote World Wide Web servers. RFC 4918 defines the extensions...
)
- As a WebDAV request may contain many sub-requests involving file operations, it may take a long time to complete the request. This code indicates that the server has received and is processing the request, but no response is available yet. This prevents the client from timing out and assuming the request was lost.
2xx Success
The action was successfully received, understood, and accepted.
This class of status code indicates that the client's request was successfully received, understood, and accepted.
200 OK
- Standard response for successful HTTP requests. The actual response will depend on the request method used. In a GET request, the response will contain an entity corresponding to the requested resource. In a POST request the response will contain an entity describing or containing the result of the action.
201 Created
- The request has been fulfilled and resulted in a new resource being created.
202 Accepted
- The request has been accepted for processing, but the processing has not been completed. The request might or might not eventually be acted upon, as it might be disallowed when processing actually takes place.
203 Non-Authoritative Information (since HTTP/1.1)
- The server successfully processed the request, but is returning information that may be from another source.
204 No Content
- The server successfully processed the request, but is not returning any content.
205 Reset Content
- The server successfully processed the request, but is not returning any content. Unlike a 204 response, this response requires that the requester reset the document view.
206 Partial Content
- The server is delivering only part of the resource due to a range header sent by the client. This is used by tools like wget
GNU Wget is a computer program that retrieves content from web servers, and is part of the GNU Project. Its name is derived from World Wide Web and get, connotative of its primary function...
to enable resuming of interrupted downloads, or split a download into multiple simultaneous streams.
207 Multi-Status (WebDAV)
- The message body that follows is an XML
XML is a set of rules for encoding documents electronically. It is defined in the produced by the W3C and several other related specifications; all are fee-free open standards....
message and can contain a number of separate response codes, depending on how many sub-requests were made.
3xx Redirection
The client must take additional action to complete the request.
This class of status code indicates that further action needs to be taken by the user agent in order to fulfil the request. The action required
may be carried out by the user agent without interaction with the user if and only if the method used in the second request is GET or HEAD. A user agent
should not automatically redirect a request more than five times, since such redirections usually indicate an
infinite loopAn infinite loop is a sequence of instructions in a computer program which loops endlessly, either due to the loop having no terminating condition, having one that can never be met, or one that causes the loop to start over. In older operating systems with cooperative multitasking, infinite loops...
.
300 Multiple Choices
- Indicates multiple options for the resource that the client may follow. It, for instance, could be used to present different format options for video, list files with different extensions, or word sense disambiguation
In computational linguistics, word sense disambiguation is the process of identifying which sense of a word is used in any given sentence, when the word has a number of distinct senses....
.
301 Moved PermanentlyThe HTTP response status code 301 Moved Permanently is used for permanent redirection.This status code should be used with the location header...
- This and all future requests should be directed to the given URI.
302 FoundThe HTTP response status code 302 Found is the most common way of performing a redirectionIt is an example of industry practice contradicting the standard HTTP/1.0 specification , which required the client to perform a temporary redirect , but popular browsers implemented it as a 303 See Other, i.e...
- This is the most popular redirect code, but also an example of industrial practice contradicting the standard. HTTP/1.0 specification required the client to perform a temporary redirect (the original describing phrase was "Moved Temporarily"), but popular browsers implemented it as a 303 See Other. Therefore, HTTP/1.1 added status codes 303 and 307 to distinguish between the two behaviours. However, the majority of Web applications and frameworks still use the 302 status code as if it were the 303.
303 See OtherThe HTTP response status code 303 See Other is the correct manner in which to redirect web applications to a new URI, particularly after an HTTP POST has been performed....
(since HTTP/1.1)
- The response to the request can be found under another URI
In computing, a Uniform Resource Identifier consists of a string of characters used to identify or name a resource on the Internet. Such identification enables interaction with representations of the resource over a network using specific protocols...
using a GET method. When received in response to a PUT, it should be assumed that the server has received the data and the redirect should be issued with a separate GET message.
304 Not Modified
- Indicates the resource has not been modified since last requested. Typically, the HTTP client provides a header like the If-Modified-Since header to provide a time against which to compare. Utilizing this saves bandwidth and reprocessing on both the server and client, as only the header data must be sent and received in comparison to the entirety of the page being re-processed by the server, then resent using more bandwidth of the server and client.
305 Use Proxy (since HTTP/1.1)
- Many HTTP clients (such as Mozilla
Mozilla is a term used in a number of ways in relation to the now-defunct Netscape Communications Corporation and its related application software, including the Mozilla.org group and its successor the Mozilla Foundation....
and Internet ExplorerWindows Internet Explorer , is a series of graphical web browsers developed by Microsoft and included as part of the Microsoft Windows line of operating systems starting in 1995...
) do not correctly handle responses with this status code, primarily for security reasons.
306 Switch Proxy
- No longer used.
307 Temporary Redirect (since HTTP/1.1)
- In this occasion, the request should be repeated with another URI, but future requests can still use the original URI. In contrast to 303, the request method should not be changed when reissuing the original request. For instance, a POST request must be repeated using another POST request.
4xx Client Error
The request contains bad syntax or cannot be fulfilled.
The 4xx class of status code is intended for cases in which the client seems to have erred. Except when responding to a HEAD request, the server
should include an entity containing an explanation of the error situation, and whether it is a temporary or permanent condition. These status codes are applicable to any request method. User agents
should display any included entity to the user. These are typically the most common error codes encountered while online.
400 Bad Request
- The request contains bad syntax or cannot be fulfilled.
401 Unauthorized
- Similar to 403 Forbidden, but specifically for use when authentication is possible but has failed or not yet been provided. The response must include a WWW-Authenticate header field containing a challenge applicable to the requested resource. See Basic access authentication and Digest access authentication
HTTP Digest access authentication is one of the agreed methods a web server can use to negotiate credentials with a web user . Digest authentication is intended to supersede unencrypted use of the Basic access authentication, allowing user identity to be established securely without having to send...
.
402 Payment Required
- The original intention was that this code might be used as part of some form of digital cash or micropayment
Micropayments are a means for transferring very small amounts of money, often in conjunction with the threshold pledge system, in situations where collecting such small amounts of money with the usual payment systems is impractical, or very expensive, in terms of the amount of money being collected...
scheme, but that has not happened, and this code has never been used.
403 ForbiddenThe 403 Forbidden HTTP status code indicates that the client was able to communicate with the server, but the server won't let the client access what was requested.This response is returned by the Apache web server when directory listings have been disabled...
- The request was a legal request, but the server is refusing to respond to it. Unlike a 401 Unauthorized response, authenticating will make no difference.
404 Not FoundThe 404 or Not Found error message is a HTTP standard response code indicating that the client was able to communicate with the server but the server could not find what was requested. 404 errors should not be confused with "server not found" or similar errors, in which a connection to the...
- The requested resource could not be found but may be available again in the future. Subsequent requests by the client are permissible.
405 Method Not Allowed
- A request was made of a resource using a request method not supported by that resource; for example, using GET on a form which requires data to be presented via POST, or using PUT on a read-only resource.
406 Not Acceptable
- The requested resource is only capable of generating content not acceptable according to the Accept headers sent in the request.
407 Proxy Authentication Required
408 Request Timeout
- The server timed out waiting for the request.
409 Conflict
- Indicates that the request could not be processed because of conflict in the request, such as an edit conflict
An edit conflict occurs when a shared document is being edited by more than one person at the same time and a conflict is generated. One person attempts to edit the document, but upon trying to save the new version, another person has already modified the document in the intervening time period,...
.
410 Gone
- Indicates that the resource requested is no longer available and will not be available again. This should be used when a resource has been intentionally removed; however, it is not necessary to return this code and a 404 Not Found can be issued instead. Upon receiving a 410 status code, the client should not request the resource again in the future. Clients such as search engines should remove the resource from their indexes.
411 Length Required
- The request did not specify the length of its content, which is required by the requested resource.
412 Precondition Failed
- The server does not meet one of the preconditions that the requester put on the request.
413 Request Entity Too Large
- The request is larger than the server is willing or able to process.
414 Request-URI Too Long
- The URI provided was too long for the server to process.
415 Unsupported Media Type
- The request did not specify any media types
An Internet media type, originally called a MIME type after MIME and sometimes a Content-type after the name of a header in several protocols whose value is such a type, is a two-part identifier for file formats on the Internet....
that the server or resource supports. For example the client specified that an image resource should be served as image/svg+xmlScalable Vector Graphics is a family of specifications of an XML-based file format for describing two-dimensional vector graphics, both static and dynamic Scalable Vector Graphics (SVG) is a family of specifications of an XML-based file format for describing two-dimensional vector graphics, both...
, but the server cannot find a matching version of the image.
416 Requested Range Not Satisfiable
- The client has asked for a portion of the file, but the server cannot supply that portion (for example, if the client asked for a part of the file that lies beyond the end of the file).
417 Expectation Failed
- The server cannot meet the requirements of the Expect request-header field.
418 I'm a teapot
- The HTCPCP server is a teapot. The responding entity MAY be short and stout
"The Teapot Song" is a song describing the heating and pouring of a teapot. The song was originally written by George Harry Sanders and Clarence Kelley and published in 1939.- Lyrics :...
. This code was defined as one of the traditional IETF April Fools' jokesAlmost every April Fools' Day since 1989, the Internet Engineering Task Force has published one or more humorous RFC documents, following in the path blazed by the June 1973 RFC 527 entitled ARPAWOCKY, which parodied Lewis Carroll's nonsense poem Jabberwocky...
, in RFC 2324, Hyper Text Coffee Pot Control ProtocolThe Hyper Text Coffee Pot Control Protocol is a protocol for controlling, monitoring, and diagnosing coffee pots.HTCPCP is specified in the jocular RFC 2324, published on...
, and is not expected to be implemented by actual HTTP servers.
422 Unprocessable Entity (WebDAV)
- The request was well-formed but was unable to be followed due to semantic errors.
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 (e.g. a PROPPATCH).
425 Unordered Collection
- Defined in drafts of WebDav Advanced Collections, but not present in "Web Distributed Authoring and Versioning (WebDAV) Ordered Collections Protocol".
426 Upgrade Required
- The client should switch to TLS/1.0
Transport Layer Security and its predecessor, Secure Sockets Layer , are cryptographic protocols that provide security for communications over networks such as the Internet...
.
449 Retry With
- A Microsoft extension. The request should be retried after doing the appropriate action.
450 Blocked by Windows Parental Controls
- A Microsoft extension. This error is given when Windows Parental Controls are turned on and are blocking access to the given webpage.
5xx Server Error
The server failed to fulfil an apparently valid request.
Response status codes beginning with the digit "5" indicate cases in which the server is aware that it has encountered an error or is otherwise incapable of performing the request. Except when responding to a HEAD request, the server
should include an entity containing an explanation of the error situation, and indicate whether it is a temporary or permanent condition. Likewise, user agents
should display any included entity to the user. These response codes are applicable to any request method.
500 Internal Server Error
- A generic error message, given when no more specific message is suitable.
501 Not Implemented
- The server either does not recognise the request method, or it lacks the ability to fulfil the request.
502 Bad Gateway
- The server was acting as a gateway or proxy and received an invalid response from the downstream server.
503 Service Unavailable
- The server is currently unavailable (because it is overloaded or down for maintenance). Generally, this is a temporary state.
504 Gateway Timeout
- The server was acting as a gateway or proxy and did not receive a timely request from the downstream server.
505 HTTP Version Not Supported
- The server does not support the HTTP protocol version used in the request.
506 Variant Also Negotiates
- Transparent content negotiation
Content negotiation is a mechanism defined in the HTTP specification that makes it possible to serve different versions of a document at the same URI, so that user agents can specify which version fit their capabilities the best...
for the request, results in a circular referenceA circular reference, sometimes referred to as a run-around, is a series of references where the last object references the first, thus causing the whole series of references to be unusable.-Circular references in business:...
.
507 Insufficient Storage (WebDAV)
509 Bandwidth Limit Exceeded (Apache bw/limited extension)
- This status code, while used by many servers, is not specified in any RFCs.
510 Not Extended
- Further extensions to the request are required for the server to fulfil it.
See also