| Code | Reference | Reason (message shown to client) | Rationale (Why is this here?) | ||||||||
| 100 | RFC 2616 # 10.1.1 | Continue | HTTP spec | ||||||||
| 101 | RFC 2616 # 10.1.2 | Switching Protocols | HTTP spec | ||||||||
| 102 | RFC 2518 | Processing | This code indicates that the server has received and is processing the request, but no response is available yet. | ||||||||
| 200 | RFC 2616 # 10.2.1 | OK | HTTP spec | ||||||||
| 201 | RFC 2616 # 10.2.2 | Created | HTTP spec | ||||||||
| 202 | RFC 2616 # 10.2.3 | Accepted | HTTP spec | ||||||||
| 203 | RFC 2616 # 10.2.4 | Non-Authoritative Information | HTTP spec | ||||||||
| 204 | RFC 2616 # 10.2.5 | No Content | HTTP spec | ||||||||
| 205 | RFC 2616 # 10.2.6 | Reset Content | HTTP spec | ||||||||
| 206 | RFC 2616 # 10.2.7 | Partial Content | HTTP spec | ||||||||
| 207 | RFC 4918 | Multi-Status | The message body that follows is an XML message and can contain a number of separate response codes, depending on how many sub-requests were made. | ||||||||
| 208 | RFC 5842 | Already Reported | The members of a DAV binding have already been enumerated in a previous reply to this request, and are not being included again. | ||||||||
| 226 | RFC 3229 | 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. | ||||||||
| 250 | RFC 2326 | Low on Storage Space | The server returns this warning after receiving a RECORD request that it may not be able to fulfill completely due to insufficient storage space. | ||||||||
| 300 | RFC 2616 # 10.3.1 | Multiple Choices | HTTP spec | ||||||||
| 301 | RFC 2616 # 10.3.2 | Moved Permanently | HTTP spec | ||||||||
| 302 | RFC 2616 # 10.3.3 | Found | HTTP spec | ||||||||
| 303 | RFC 2616 # 10.3.4 | See Other | HTTP spec | ||||||||
| 304 | RFC 2616 # 10.3.5 | Not Modified | HTTP spec | ||||||||
| 305 | RFC 2616 # 10.3.6 | Use Proxy | HTTP spec | ||||||||
| 307 | RFC 2616 # 10.3.8 | Temporary Redirect | HTTP spec | ||||||||
| 308 | proposed | Resume Incomplete | http://tools.ietf.org/html/draft-reschke-http-status-308-07 | ||||||||
| 400 | RFC 2616 # 10.4.1 | Bad Request | HTTP spec | ||||||||
| 401 | RFC 2616 # 10.4.2 | Unauthorized | HTTP spec | ||||||||
| 402 | RFC 2616 # 10.4.3 | Payment Required | HTTP spec | ||||||||
| 403 | RFC 2616 # 10.4.4 | Forbidden | HTTP spec | ||||||||
| 404 | RFC 2616 # 10.4.5 | Not Found | HTTP spec | ||||||||
| 405 | RFC 2616 # 10.4.6 | Method Not Allowed | HTTP spec | ||||||||
| 406 | RFC 2616 # 10.4.7 | Not Acceptable | HTTP spec | ||||||||
| 407 | RFC 2616 # 10.4.8 | Proxy Authentication Required | HTTP spec | ||||||||
| 408 | RFC 2616 # 10.4.9 | Request Time-out | HTTP spec | ||||||||
| 409 | RFC 2616 # 10.4.10 | Conflict | HTTP spec | ||||||||
| 410 | RFC 2616 # 10.4.11 | Gone | HTTP spec | ||||||||
| 411 | RFC 2616 # 10.4.12 | Length Required | HTTP spec | ||||||||
| 412 | RFC 2616 # 10.4.13 | Precondition Failed | HTTP spec | ||||||||
| 413 | RFC 2616 # 10.4.14 | Request Entity Too Large | HTTP spec | ||||||||
| 414 | RFC 2616 # 10.4.15 | Request-URI Too Large | HTTP spec | ||||||||
| 415 | RFC 2616 # 10.4.16 | Unsupported Media Type | HTTP spec | ||||||||
| 416 | RFC 2616 # 10.4.17 | Requested range not satisfiable | HTTP spec | ||||||||
| 417 | RFC 2616 # 10.4.18 | Expectation Failed | HTTP spec | ||||||||
| 422 | RFC 4918 | Unprocessable Entity | The request was well-formed but was unable to be followed due to semantic errors. | ||||||||
| 423 | RFC 4918 | Locked | The resource that is being accessed is locked. | ||||||||
| 424 | RFC 4918 | Failed Dependency | The request failed due to failure of a previous request (e.g. a PROPPATCH). | ||||||||
| 424 | RFC 4918 | Method Failure | Indicates the method was not executed on a particular resource within its scope because some part of the method's execution failed causing the entire method to be aborted. | ||||||||
| 425 | RFC 3648 | Unordered Collection | Defined in "WebDAV Advanced Collections Protocol". | ||||||||
| 426 | RFC 2817 | Upgrade Required | The client should switch to a different protocol such as TLS/1.0. | ||||||||
| 428 | RFC 6585 | Precondition Required | The origin server requires the request to be conditional. Intended to prevent "the 'lost update' problem, where a client GETs a resource's state, | ||||||||
| 429 | RFC 6585 | Too Many Requests | The user has sent too many requests in a given amount of time. Intended for use with rate limiting schemes. | ||||||||
| 431 | RFC 6585 | Request Header Fields Too Large | The server is unwilling to process the request because either an individual header field, or all the header fields collectively, are too large. | ||||||||
| 444 | Nginx | No Response | Used in Nginx logs to indicate that the server has returned no information to the client and closed the connection (useful as a deterrent for malware). | ||||||||
| 449 | MSFT | Retry With | A Microsoft extension. The request should be retried after performing the appropriate action. Often search-engines or custom applications will ignore required parameters. Where no default action is appropriate, the Aviongoo website sends a "HTTP/1.1 449 Retry with valid parameters: param1, param2, . . ." response. The applications may choose to learn, or not. | ||||||||
| 450 | MSFT | 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. | ||||||||
| 451 | RFC 2326 | Parameter Not Understood | The recipient of the request does not support one or more parameters contained in the request. | ||||||||
| 451 | proposed | Unavailable For Legal Reasons | http://tools.ietf.org/html/draft-tbray-http-legally-restricted-status-00 | ||||||||
| 452 | RFC 2326 | Conference Not Found | The conference indicated by a Conference header field is unknown to the media server. | ||||||||
| 453 | RFC 2326 | Not Enough Bandwidth | The request was refused because there was insufficient bandwidth. This may, for example, be the result of a resource reservation failure. | ||||||||
| 454 | RFC 2326 | Session Not Found | The RTSP session identifier in the Session header is missing, invalid, or has timed out. | ||||||||
| 455 | RFC 2326 | Method Not Valid in This State | The client or server cannot process this request in its current state. The response SHOULD contain an Allow header to make error recovery easier. | ||||||||
| 456 | RFC 2326 | Header Field Not Valid for Resource | The server could not act on a required request header. For example, if PLAY contains the Range header field but the stream does not allow seeking. | ||||||||
| 457 | RFC 2326 | Invalid Range | The Range value given is out of bounds, e.g., beyond the end of the presentation. | ||||||||
| 458 | RFC 2326 | Parameter Is Read-Only | The parameter to be set by SET_PARAMETER can be read but not modified. | ||||||||
| 459 | RFC 2326 | Aggregate Operation Not Allowed | The requested method may not be applied on the URL in question since it is an aggregate (presentation) URL. The method may be applied on a stream URL. | ||||||||
| 460 | RFC 2326 | Only Aggregate Operation Allowed | The requested method may not be applied on the URL in question since it is not an aggregate (presentation) URL. The method may be applied on the presentation URL. | ||||||||
| 461 | RFC 2326 | Unsupported Transport | The Transport field did not contain a supported transport specification. | ||||||||
| 462 | RFC 2326 | Destination Unreachable | The data transmission channel could not be established because the client address could not be reached. This error will most likely be the result of a client attempt to place an invalid Destination parameter in the Transport field. | ||||||||
| 500 | RFC 2616 # 10.5.1 | Internal Server Error | HTTP spec | ||||||||
| 501 | RFC 2616 # 10.5.2 | Not Implemented | HTTP spec | ||||||||
| 502 | RFC 2616 # 10.5.3 | Bad Gateway | HTTP spec | ||||||||
| 503 | RFC 2616 # 10.5.4 | Service Unavailable | HTTP spec | ||||||||
| 504 | RFC 2616 # 10.5.5 | Gateway Time-out | HTTP spec | ||||||||
| 505 | RFC 2616 # 10.5.6 | HTTP Version not supported | HTTP spec | ||||||||
| 506 | RFC 2295 | Variant Also Negotiates | Transparent content negotiation for the request results in a circular reference. | ||||||||
| 507 | RFC 4918 | Insufficient Storage | The server is unable to store the representation needed to complete the request. | ||||||||
| 508 | RFC 5842 | Loop Detected | The server detected an infinite loop while processing the request (sent in lieu of 208). | ||||||||
| 509 | Apache | Bandwidth Limit Exceeded | This status code, while used by many servers, is not specified in any RFCs. Apache-specific. | ||||||||
| 510 | RFC 2774 | Not Extended | Further extensions to the request are required for the server to fulfill it. | ||||||||
| 511 | RFC 6585 | Network Authentication Required | 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 | ||||||||
| 551 | RFC 2326 | Option not supported | An option given in the Require or the Proxy-Require fields was not supported. The Unsupported header should be returned stating the option for which there is no support. | ||||||||
| 1000 | new | DNS: Name service failure | Indicates a DNS failure for unknown reasons | ||||||||
| 1001 | new | DNS: Unknown host | This indicates socket receives an unknown host error from DNS | ||||||||
| 1002 | new | DNS: Lookup Failure | Client was unable to resolve DNS either due to no DNS server being available or no valid response returned. | ||||||||
| 1100 | new | TCP: Connection Error | This indicates a general connection error | ||||||||
| 1101 | new | TCP: Connection refused | This indicates a request to connect to the server is refused | ||||||||
| 1102 | new | TCP: Connection timeout | This indicates there is no activity in socket connection in N seconds. | ||||||||
| 1103 | new | TCP: Connection reset | This indicates socket receive a reset signal from the server | ||||||||
| 1104 | new | TCP: Socket error | This indicates a general socket error | ||||||||
| 1105 | new | TCP: Socket protocol error | This indicates an error in socket protocol | ||||||||
| 1106 | new | TCP: Socket unexpected close | This indicates socket connection has been closed unexpectedly | ||||||||
| 1107 | new | TCP: Socket bind error | This indicates an error in binding the socket | ||||||||
| 1108 | new | TCP: Socket receive timeout | This socket exceeded its timeout to receive data | ||||||||
| 1109 | new | TCP: No route to host | This indicates a no route to host error was received while attempting to open a socket | ||||||||
| 1110 | new | TCP: Unknown Connection | This connection cannot be made due to lack of information | ||||||||
| 1200 | new | SSL: Connection failure | This indicates a SSL failure for unknown reasons | ||||||||
| 1201 | new | SSL: Timeout | This indicates a timeout during SSL handshake (2 minutes) | ||||||||
| 1202 | new | SSL: End of input | This indicates an end-of-file is received during SSL handshake | ||||||||
| 1203 | new | SSL: Handshake error | This indicates a general error during SSL handshake | ||||||||
| 1204 | new | SSL: Certificate verification error | This indicates an error in SSL certificate verification | ||||||||
| 1205 | new | SSL: Authentication error | This indicates an authentication error during SSL handshake | ||||||||
| 1206 | new | SSL: Bad MAC | This indicates a bad MAC during SSL handshake | ||||||||
| 1207 | new | SSL: Cipher error | This indicates a cipher error during SSL handshake | ||||||||
| 1208 | new | SSL: Unsupported SSL Version | SSL version mismatch | ||||||||
| 1209 | new | SSL: Client certificate Error | This error is used when SSL client certificate error occurred to distinguish it from 4XX in a log and an error page redirection. (Nginx) | ||||||||
| 1210 | new | SSL: No SSL certificate | This error is used when client didn't provide certificate to distinguish it from 4XX in a log and an error page redirection. (Nginx) | ||||||||
| 1211 | new | SSL: HTTP to HTTPS | This error is used for the plain HTTP requests that are sent to HTTPS port to distinguish it from 4XX in a log and an error page redirection. (Nginx) | ||||||||
| 1300 | new | HTTP: Invalid URL | URL is invalid | ||||||||
| 1301 | new | HTTP: Redirect error | This indicates an error in redirect HTTP header | ||||||||
| 1302 | new | HTTP: Header malformed | This indicates a malformed HTTP header | ||||||||
| 1303 | new | HTTP: Empty HTTP response | This indicates server doesn't send any response after a request is sent | ||||||||
| 1304 | new | HTTP: Incomplete Response | This indicates sever sends an incomplete page/object (as indicated by Content-Length header) | ||||||||
| 1305 | new | HTTP: Frame loop | This indicates a page has a frame loop (frame A includes Frame B that includes Frame A) | ||||||||
| 1306 | new | HTTP: Redirect loop | This indicates a page has a redirect loop (page A redirects to page B that redirects to page A) | ||||||||
| 1307 | new | HTTP: Chunked encoding error | This indicates an error in chunked encoding | ||||||||
| 1308 | new | HTTP: Excessive Number of Redirects | Too many redirects | ||||||||
| 1400 | new | Client: Client failure unknown | The client is unable to complete the request for unknown reasons | ||||||||
| 1401 | new | Client: Byte Limit Exceeded | Indicates that the client has received more bytes than some predefined limit | ||||||||
| 1402 | new | Client: TimeOut Exceeded | Arbitrary session/client timeout | ||||||||
| 1403 | new | Client: Client closed request | Used to indicate when the connection has been closed by client while the server is still processing its request, making server unable to send a status code back. (Nginx) | ||||||||
| RFC Key | |||||||||||
| 2616 | HTTP 1.1 | ||||||||||
| 2326 | RSTP | ||||||||||
| 4918 | WebDAV | ||||||||||
| 3648 | WebDAV | ||||||||||
| 5862 | WebDAV | ||||||||||
| 2774 | HTTP Ext | ||||||||||
| 6585 | HTTP Ext | ||||||||||
| 2295 | Content Negotiation | ||||||||||
| 2817 | TLS+HTTP | ||||||||||
| 2518 | WebDAV | ||||||||||
| 3229 | HTTP Deltas | ||||||||||
| 5842 | WebDAV | ||||||||||