Status codes defined by IETF are listed below. Emphasized terms , and are interpretation guidelines as given by .
1xx informational response An informational response indicates that the request was received and understood and is being processed. It alerts the client to wait for a final response. The message does not contain a body. As the HTTP/1.0 standard did not define any 1xx status codes, servers send a 1xx response to an HTTP/1.0 compliant client except under experimental conditions. ;100 Continue : The server has received the request headers and the client should proceed to send the request body (in the case of a request for which a body needs to be sent, such as a
POST request). Sending a large request body to a server after a request has been rejected for inappropriate headers would be inefficient. To have a server check the request's headers, a client must send Expect: 100-continue as a header in its initial request and receive a 100 Continue status code in response before sending the body. If the client receives an error code such as 403 (Forbidden) or 405 (Method Not Allowed) then it should not send the request's body. The response 417 Expectation Failed indicates that the request should be repeated without the Expect header as it indicates that the server does not support expectations (this is the case, for example, of HTTP/1.0 servers). ;101 Switching Protocols : The requester has asked the server to switch protocols and the server has agreed to do so. ;102 Processing (
WebDAV; RFC 2518) : A WebDAV request may contain many sub-requests involving file operations, requiring 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. The status code is deprecated. ;103 Early Hints (RFC 8297) :Used to return some response headers before final HTTP message.
2xx success A success status indicates that the action requested by the client was received, understood, and accepted. ;202 Accepted : The request has been accepted for processing, but the processing has not been completed. The request might or might not be eventually acted upon, and may be disallowed when processing occurs. ;203 Non-Authoritative Information (since HTTP/1.1) : The server is a transforming proxy (e.g. a ) that received a 200 OK from its origin, but is returning a modified version of the origin's response. ;204 No Content : The server successfully processed the request, and is not returning any content. ;205 Reset Content : The server successfully processed the request, asks that the requester reset its document view, and is not returning any content. ;206 Partial Content : The server is delivering only part of the resource (
byte serving) due to a range header sent by the client. The range header is used by HTTP clients to enable resuming of interrupted downloads, or split a download into multiple simultaneous streams. ;207 Multi-Status (WebDAV; RFC 4918) : The message body that follows is by default an
XML message and can contain a number of separate response codes, depending on how many sub-requests were made. ;208 Already Reported (WebDAV; RFC 5842) : The members of a DAV binding have already been enumerated in a preceding part of the (multistatus) response, and are not being included again. ;226 IM Used (RFC 3229) : The server has fulfilled a 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 redirection A 3xx status indicates that the client must take additional action, generally
URL redirection, to complete the request. :This code is considered best practice for upgrading users from HTTP to
HTTPS. Both
Bing and
Google recommend using this code to change the URL of a page as it is shown in search engine results, providing that URL will permanently change and is not due to be changed again any time soon. ;302 Found : Indicates that the resource is accessible via an alternate URL indicated in the
Location header field. The HTTP/1.0 specification (which used reason phrase "Moved Temporarily") required the client to redirect with the same method, but popular browsers instead changed the request to GET. For this reason, HTTP/1.1 () added two status codes: 303 which requires changing the request to a GET and 307 which preserves the original request type. Despite the greater clarity provided by this disambiguation, the 302 code is still used in web frameworks to preserve compatibility with browsers that do not support HTTP/1.1. As a consequence, (the update of ) changes the definition to allow user agents to rewrite POST to GET. ;303 See Other (since HTTP/1.1) : If a server responds to a POST or other non-idempotent request with this code and a
location header field, the client is expected to issue a GET request to the specified location. To trigger a request to the target resource using the same method, the server responds with 307 instead. : Use of this code has been proposed as one way of responding to a request for a
URI that identifies a real-world object according to
Semantic Web theory (the other being the use of
hash URIs). ;304 Not Modified : Indicates that the resource has not been modified since the version specified by the
request headers If-Modified-Since or If-None-Match. In such case, there is no need to retransmit the resource since the client still has a previously-downloaded copy. ;305 Use Proxy (since HTTP/1.1) :The requested resource is available only through a proxy, the address for which is provided in the response. For security reasons, many HTTP clients (such as
Mozilla Firefox and
Internet Explorer) do not obey this status code. ;306 Switch Proxy : No longer used. Originally meant "Subsequent requests should use the specified proxy." ;307 Temporary Redirect (since HTTP/1.1) : In this case, the request should be repeated with another URI; however, future requests should still use the original URI. In contrast to how 302 was historically implemented, the request method is not allowed to be changed when reissuing the original request. For example, a POST request should be repeated using another POST request. ;308 Permanent Redirect : This and all future requests should be directed to the given
URI. 308 parallels the behavior of 301, but . So, for example, submitting a form to a permanently redirected resource may continue smoothly.
4xx client error A 4xx status code is for situations in which an error seems to have been caused by the client. Except when responding to a HEAD request, the server 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 display any included entity to the user. ;400 Bad Request : The server cannot or will not process the request due to an apparent client error (e.g., malformed request syntax, size too large, invalid request message framing, or deceptive request routing). ;401 Unauthorized : Similar to 403 Forbidden, but specifically for use when authentication is required and has failed or has 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. 401 semantically means "unauthenticated", the user does not have valid authentication credentials for the target resource. ;402 Payment Required : Reserved for future use. The original intention was that this code might be used as part of some form of
digital cash or
micropayment scheme, as proposed, for example, by
GNU Taler, but that has not yet happened, and this code is not widely used.
Google Developers API uses this status if a particular developer has exceeded the daily limit on requests.
Sipgate uses this code if an account does not have sufficient funds to start a call.
Shopify uses this code when the store has not paid their fees and is temporarily disabled.
Stripe uses this code for failed payments where parameters were correct, for example blocked fraudulent payments.
Cloudflare Turnstile uses this code when requesting resources with
cURL. :
x402 is an open standard for internet-native transactions built on the HTTP protocol. It repurposes the HTTP 402 "Payment Required" status code to enable cryptographic, peer-to-peer payments directly within HTTP request-response cycles. ;403 Forbidden : The request was valid, but the server refuses action. This may be due to the user not having permission to a resource or needing an account of some sort, or attempting a prohibited action (e.g. creating a duplicate record where only one is allowed). This code is also typically used if the request provided authentication by answering the WWW-Authenticate header field challenge, but the server did not accept that authentication. The request should not be repeated. : This code differs from 401 in that while 401 is returned when the client has not authenticated, and implies that a successful response may be returned following valid authentication, 403 is returned when the client is not permitted access to the resource despite providing authentication such as insufficient permissions of the authenticated account. : The
Apache web server returns 403 in response to a request for
URL ;404 Not Found : The requested resource could not be found but may be available in the future. Subsequent requests by the client are permissible. ;405 Method Not Allowed : A request method is not supported for the requested resource (for example, a GET request on a form that requires data to be presented via
POST, or a PUT request on a read-only resource). ;406 Not Acceptable : The requested resource is capable of generating only content not acceptable according to the Accept headers sent in the request. See
Content negotiation. ;407 Proxy Authentication Required :The client must first authenticate itself with the
proxy. ;408 Request Timeout : The server timed out waiting for the request. According to HTTP specifications: "The client did not produce a request within the time that the server was prepared to wait. The client MAY repeat the request without modifications at any later time." ;409 Conflict : Indicates that the request could not be processed because of conflict in the current state of the resource, such as an
edit conflict between multiple simultaneous updates. ;410 Gone : Indicates that the resource requested was previously in use but is no longer available and will not be available again. This should be used when a resource has been intentionally removed and the resource should be purged. Upon receiving a 410 status code, the client should not request the resource in the future. Clients such as search engines should remove the resource from their indices. Most use cases do not require clients and search engines to purge the resource, and a "404 Not Found" may be used instead. ;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 header fields. ;413 Content Too Large : The request is larger than the server is willing or able to process. Previously called "Request Entity Too Large" and "Payload Too Large". ;414 URI Too Long : The
URI provided was too long for the server to process. Often the result of too much data being encoded as a query-string of a GET request, in which case it should be converted to a POST request. Called "Request-URI Too Long" previously. ;415 Unsupported Media Type : The request entity has a
media type which the server or resource does not support. For example, the client uploads an image as
image/svg+xml, but the server requires that images use a different format. ;416 Range Not Satisfiable : The client has asked for a portion of the file (
byte serving), 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. Called "Requested Range Not Satisfiable" previously. ;417 Expectation Failed : The server cannot meet the requirements of the Expect request-header field. ;418 I'm a teapot (RFC 2324, RFC 7168) :This code was defined in 1998 as one of the traditional
IETF April Fools' jokes, in RFC 2324,
Hyper Text Coffee Pot Control Protocol, and is not expected to be implemented by actual HTTP servers. The RFC specifies this code should be returned by teapots requested to brew coffee. This HTTP status is used as an
Easter egg in some websites, such as
Google.com's "I'm a teapot" easter egg. Sometimes, this status code is also used as a response to a blocked request, instead of the more appropriate 403 Forbidden. ;421 Misdirected Request : The request was directed at a server that is not able to produce a response (for example because of connection reuse). ;422 Unprocessable Content : The request was well-formed (i.e., syntactically correct) but could not be processed. ;423 Locked (WebDAV; RFC 4918) : The resource that is being accessed is locked. ;424 Failed Dependency (WebDAV; RFC 4918) : The request failed because it depended on another request and that request failed (e.g., a PROPPATCH). ;425 Too Early (RFC 8470) :Indicates that the server is unwilling to risk processing a request that might be replayed. ;426 Upgrade Required : The client should switch to a different protocol such as
TLS/1.3, given in the
Upgrade header field. ;428 Precondition Required (RFC 6585) :The origin server requires the request to be conditional. Intended to prevent the 'lost update' problem, where a client GETs a resource's state, modifies it, and PUTs it back to the server, when meanwhile a third party has modified the state on the server, leading to a conflict. ;429 Too Many Requests (RFC 6585) :The user has sent too many requests in a given amount of time. Intended for use with
rate-limiting schemes. The code 451 was chosen as a reference to the novel
Fahrenheit 451.
5xx server error 5xx status indicates that 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 include an entity containing an explanation of the error situation, and indicate whether it is a temporary or permanent condition. Likewise, user agents 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 an unexpected condition was encountered and no more specific message is suitable. ;501 Not Implemented : The server either does not recognize the request method, or it lacks the ability to fulfil the request. Usually this implies future availability (e.g., a new feature of a web-service API). ;502 Bad Gateway : The server was acting as a
gateway or proxy and received an invalid response from the upstream server. ;503 Service Unavailable : The server cannot handle the request (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 response from the upstream server. ;505 HTTP Version Not Supported : The server does not support the HTTP version used in the request. ;506 Variant Also Negotiates (RFC 2295) : Transparent
content negotiation for the request results in a
circular reference. ;507 Insufficient Storage (WebDAV; RFC 4918) : The server is unable to store the representation needed to complete the request. ;508 Loop Detected (WebDAV; RFC 5842) : The server detected an infinite loop while processing the request (sent instead of
208 Already Reported). ;510 Not Extended (RFC 2774) : Further extensions to the request are required for the server to fulfil it. ;511 Network Authentication Required (RFC 6585) :The client needs to authenticate to gain network access. Intended for use by intercepting proxies used to control access to the network (e.g., "
captive portals" used to require agreement to Terms of Service before granting full Internet access via a
Wi-Fi hotspot). : ==Nonstandard codes==