HTTP Status Codes

1xx informational·3

• 100ContinueThe initial request headers have been received; the client should continue with the body.
• 101Switching ProtocolsThe server is switching protocols as requested via the Upgrade header.
• 103Early HintsUsed with Link headers to allow the user agent to start preloading resources while the server prepares a response.

2xx success·5

• 200OKStandard success response for GET, PUT and POST requests.
• 201CreatedThe request succeeded and a new resource was created. Often returned by POST and PUT.
• 202AcceptedThe request has been accepted for processing but is not yet complete.
• 204No ContentThe server fulfilled the request and is not returning any content.
• 206Partial ContentReturned when the client requests a byte range with the Range header.

3xx redirect·5

• 301Moved PermanentlyThe resource has a new permanent URL — clients should update their bookmarks.
• 302FoundThe resource is temporarily at a different URL.
• 304Not ModifiedThe cached copy is still valid; no body is returned.
• 307Temporary RedirectLike 302, but the request method must not change.
• 308Permanent RedirectLike 301, but the request method must not change.

4xx client error·23

• 400Bad RequestThe server cannot process the request due to a client error such as malformed syntax.
• 401UnauthorizedAuthentication is required and has either failed or not yet been provided.
• 402Payment RequiredReserved for future use; rarely seen in practice.
• 403ForbiddenThe server understood the request but refuses to authorise it.
• 404Not FoundThe requested resource could not be found.
• 405Method Not AllowedThe request method is known by the server but not supported by the target resource.
• 406Not AcceptableThe server cannot produce a response matching the client's Accept headers.
• 408Request TimeoutThe server timed out waiting for the request.
• 409ConflictThe request conflicts with the current state of the resource.
• 410GoneThe resource has been permanently removed and will not return.
• 411Length RequiredThe request did not specify the length of its content, which is required.
• 412Precondition FailedPreconditions from headers like If-Match or If-Unmodified-Since were not met.
• 413Payload Too LargeThe request entity is larger than the server is willing or able to process.
• 414URI Too LongThe URI provided is too long for the server to interpret.
• 415Unsupported Media TypeThe payload's media type is not supported.
• 418I'm a teapotApril-fools status from RFC 2324 — the server refuses to brew coffee because it is a teapot.
• 422Unprocessable EntityThe request was well-formed but contained semantic errors.
• 425Too EarlyThe server is unwilling to risk processing a request that might be replayed.
• 426Upgrade RequiredThe client must switch to a different protocol such as TLS 1.3.
• 428Precondition RequiredThe origin server requires the request to be conditional.
• 429Too Many RequestsThe user has sent too many requests in a given amount of time (rate limiting).
• 431Request Header Fields Too LargeThe server is unwilling to process the request because its headers are too large.
• 451Unavailable For Legal ReasonsThe resource is unavailable due to legal demands.

5xx server error·9

• 500Internal Server ErrorA generic catch-all error message when an unexpected condition was encountered.
• 501Not ImplementedThe server does not support the functionality required to fulfil the request.
• 502Bad GatewayThe server, while acting as a gateway or proxy, received an invalid response from the upstream.
• 503Service UnavailableThe server is not ready to handle the request — usually overloaded or down for maintenance.
• 504Gateway TimeoutThe upstream server failed to send a response in time.
• 505HTTP Version Not SupportedThe HTTP version used in the request is not supported by the server.
• 507Insufficient StorageThe server cannot store the representation needed to complete the request.
• 508Loop DetectedThe server detected an infinite loop while processing the request.
• 511Network Authentication RequiredThe client needs to authenticate to gain network access (e.g. captive portals).