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. |
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. |
| 204 No Content | The server successfully processed the request and is not returning any content. |
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. |
| 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. |
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. |
| 429 Too Many Requests | The user has sent too many requests in a given amount of time ('rate limiting'). |
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. |
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