Request received, continuing process. These are temporary responses. 100 Continue: The server has received the request headers and the client should proceed to send the request body. | 101 Switching Protocols: The requester has asked the server to switch protocols and the server has agreed to do so. | 102 Processing: The server has received and is processing the request, but no response is available yet.

The action was successfully received, understood, and accepted. 200 OK: Standard response for successful HTTP requests. | 201 Created: The request has been fulfilled, resulting in the creation of a new resource. | 202 Accepted: The request has been accepted for processing, but the processing has not been completed.

Further action must be taken in order to complete the request. 301 Moved Permanently: This and all future requests should be directed to the given URI. | 302 Found: Commonly used for temporary redirection. The URI of the requested resource has been changed temporarily. | 303 See Other: The response can be found under a different URI using a GET method.

The request contains bad syntax or cannot be fulfilled. 400 Bad Request: The server cannot or will not process the request due to an apparent client error (e.g., malformed request syntax). | 401 Unauthorized: Similar to 403 Forbidden, but specifically for use when authentication is required and has failed or has not yet been provided. | 403 Forbidden: The request was valid, but the server is refusing action. The user might not have the necessary permissions for a resource.

The server failed to fulfill an apparently valid request. 500 Internal Server Error: A generic error message, given when an unexpected condition was encountered and no more specific message is suitable. | 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 is currently unavailable (because it is overloaded or down for maintenance).

HTTP Status Codes

A comprehensive reference for HTTP response status codes. These codes are issued by a server in response to a client's request using HTTP.

1xx: Informational

Request received, continuing process. These are temporary responses.

Key / Code	Description
100 Continue	The server has received the request headers and the client should proceed to send the request body.
101 Switching Protocols	The requester has asked the server to switch protocols and the server has agreed to do so.
102 Processing	The server has received and is processing the request, but no response is available yet.
103 Early Hints	Provides hints to the client about resources that can be preloaded while the server prepares the response.

2xx: Success

The action was successfully received, understood, and accepted.

Key / Code	Description
200 OK	Standard response for successful HTTP requests.
201 Created	The request has been fulfilled, resulting in the creation of a new resource.
202 Accepted	The request has been accepted for processing, but the processing has not been completed.
203 Non-Authoritative Information	The response is from a transforming proxy and not the origin server.
204 No Content	The server successfully processed the request and is not returning any content.
205 Reset Content	Tells the client to reset the document view.
206 Partial Content	Delivers a partial response due to a range header sent by the client.

3xx: Redirection

Further action must be taken in order to complete the request.

Key / Code	Description
301 Moved Permanently	This and all future requests should be directed to the given URI.
302 Found	Commonly used for temporary redirection. The URI of the requested resource has been changed temporarily.
303 See Other	The response can be found under a different URI using a GET method.
304 Not Modified	Indicates that the resource has not been modified since the version specified by If-Modified-Since or If-None-Match.
307 Temporary Redirect	The request should be repeated with another URI; method and body must not change.
308 Permanent Redirect	The request and all future requests should be repeated using another URI; method and body must not change.

4xx: Client Error

The request contains bad syntax or cannot be fulfilled.

Key / Code	Description
400 Bad Request	The server cannot or will not process the request due to an apparent client error (e.g., malformed request syntax).
401 Unauthorized	Similar to 403 Forbidden, but specifically for use when authentication is required and has failed or has not yet been provided.
403 Forbidden	The request was valid, but the server is refusing action. The user might not have the necessary permissions for a resource.
404 Not Found	The requested resource could not be found but may be available in the future.
405 Method Not Allowed	The request method is known by the server but not supported by the target resource.
406 Not Acceptable	The requested resource can only generate content not acceptable according to the Accept headers.
408 Request Timeout	The server timed out waiting for the request.
409 Conflict	The request could not be completed due to a conflict with the current state of the resource.
410 Gone	The resource requested is no longer available and will not be available again.
412 Precondition Failed	One or more conditions given in the request headers evaluated to false.
413 Payload Too Large	The request entity is larger than limits defined by server.
415 Unsupported Media Type	The media type of the request data is not supported by the server.
422 Unprocessable Entity	The request was well-formed but unable to be followed due to semantic errors.
429 Too Many Requests	The user has sent too many requests in a given amount of time ('rate limiting').
431 Request Header Fields Too Large	The server is unwilling to process the request because header fields are too large.

5xx: Server Error

The server failed to fulfill an apparently valid request.

Key / Code	Description
500 Internal Server Error	A generic error message, given when an unexpected condition was encountered and no more specific message is suitable.
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 is currently unavailable (because it is overloaded or down for maintenance).
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 protocol version used in the request.
507 Insufficient Storage	The server is unable to store the representation needed to complete the request.

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