Some Common Internet Error Codes With Meanings

100 Continue
101 Switching Protocols
102 Processing (WebDAV; RFC 2518)
200 OK
201 Created
202 Accepted
203 Non-Authoritative Information (since HTTP/1.1)
204 No Content
205 Reset Content
206 Partial Content
207 Multi-Status (WebDAV; RFC 4918)
208 Already Reported (WebDAV; RFC 5842)
226 IM Used (RFC 3229)
300 Multiple Choices
301 Moved Permanently
302 Found
303 See Other (since HTTP/1.1)
304 Not Modified
305 Use Proxy (since HTTP/1.1)
306 Switch Proxy
307 Temporary Redirect (since HTTP/1.1)
308 Permanent Redirect (approved as experimental RFC)[12]
400 Bad Request
401 Unauthorized
402 Payment Required
403 Forbidden
404 Not Found
405 Method Not Allowed
406 Not Acceptable
407 Proxy Authentication Required
408 Request Timeout
409 Conflict
410 Gone
411 Length Required
412 Precondition Failed
413 Request Entity Too Large
414 Request-URI Too Long
415 Unsupported Media Type
416 Requested Range Not Satisfiable
417 Expectation Failed
418 I'm a teapot (RFC 2324)
419 Authentication Timeout (not in RFC 2616)
420 Method Failure (Spring Framework)
420 Enhance Your Calm (Twitter)
422 Unprocessable Entity (WebDAV; RFC 4918)
423 Locked (WebDAV; RFC 4918)
424 Failed Dependency (WebDAV; RFC 4918)
424 Method Failure (WebDAV)[14]
425 Unordered Collection (Internet draft)
426 Upgrade Required (RFC 2817)
428 Precondition Required (RFC 6585)
429 Too Many Requests (RFC 6585)
431 Request Header Fields Too Large (RFC 6585)
440 Login Timeout
444 No Response (Nginx)
449 Retry With (Microsoft)
450 Blocked by Windows Parental Controls (Microsoft)
451 Unavailable For Legal Reasons (Internet draft)
451 Redirect (Microsoft)
494 Request Header Too Large (Nginx)
495 Cert Error (Nginx)
496 No Cert (Nginx)
497 HTTP to HTTPS (Nginx)
499 Client Closed Request (Nginx)
500 Internal Server Error
501 Not Implemented
502 Bad Gateway
503 Service Unavailable
504 Gateway Timeout
505 HTTP Version Not Supported
506 Variant Also Negotiates (RFC 2295)
507 Insufficient Storage (WebDAV; RFC 4918)
508 Loop Detected (WebDAV; RFC 5842)
509 Bandwidth Limit Exceeded (Apache bw/limited extension)
510 Not Extended (RFC 2774)
511 Network Authentication Required (RFC 6585)
522 Connection timed out
524 A timeout occurred
598 Network read timeout error (Unknown)
599 Network connect timeout error (Unknown)