Knowledge base
HTTP status code overview
Quickly identify what every server status code means, why it appears, and where to focus when troubleshooting.
Decode every response
Servers use five families of status codes to describe how a request was processed. Knowing the difference between 2xx, 3xx, 4xx, and 5xx responses keeps outages short and redirects purposeful.
- 1xx = informational, 2xx = success, 3xx = redirect, 4xx = client error, 5xx = server error.
- Look for repeated 4xx/5xx entries in your logs to spot misconfigurations or crawling issues.
- Use this list as a browser or API troubleshooting companion before chasing hosting issues.
Status code reference
HTTP 1xx – Informational
| Code | Meaning | Explanation |
|---|---|---|
| 100 | Continue | The client has sent a request properly and should therefore continue. |
| 101 | Switching Protocols | The client requires a different communication protocol. The server understood the request and agrees to the change. |
HTTP 2xx – Success
| Code | Meaning | Explanation |
|---|---|---|
| 200 | Successful | The request of the client has been successfully processed and all information sent by the server. |
| 201 | Created | The client has caused the server to create a new document. In the header of the new source is named. |
| 202 | Accepted | The request of the client from the server was understood and accepted but not processed. |
| 203 | Non-Authorative Information | The client receives from the server information originating from a source other than the server. |
| 204 | No Content | The server understood the request, but only sends the header without body to the client. |
| 205 | Reset Content | The request was successful, and the client should build the document. |
| 206 | Partial Content | The client has requested only a part of document in his header. |
HTTP 3xx – Redirect
| Code | Meaning | Explanation |
|---|---|---|
| 300 | Multiple Choices | The client has requested a resource for that several sources are possible. |
| 301 | Moved Permanently | The requested resource has permanently moved to another location. |
| 302 | Moved Temporarily | The requested resource has been moved just temporarily. |
| 303 | See Other | The client has requested a resource that is still available from elsewhere. |
| 304 | Not Modified | The requested resource has not changed since the last request. |
| 305 | Use Proxy | The resource that was requested, should not be obtained from the server, but rather through a specified proxy. |
| 307 | Moved temporarily | The client has requested a resource that is currently to be found elsewhere. |
HTTP 4xx – Client error
| Code | Meaning | Explanation |
|---|---|---|
| 400 | Bad Request | The request of the client was not understood by the server. |
| 401 | Unauthorized | The request required a user or client authentication. |
| 402 | Payment Required | It was requested a paid resource. A status code for the future. |
| 403 | Forbidden | The request was understood, the execution was banned from the server. |
| 404 | Not Found | The requested resource was not found. |
| 405 | Method Not Allowed | The method that was specified for execution is not allowed for this resource (Get or Post). |
| 406 | Not Acceptable | The client has requested a resource whose format does not support it according to its own information. |
| 407 | Proxy Authentication Required | The used proxy requires authentication. |
| 408 | Request Timeout | The client did not send a complete request within the expected or acceptable waiting time. |
| 409 | Conflict | By the status of the requested resource, the request from the server could not be executed. |
| 410 | Gone | The resource is no longer available on the server and a new place is not known. |
| 411 | Length Required | With the request of the client lacked the specified length (number of bytes) of the resource. |
| 412 | Precondition Failed | The If conditioned client request could not be processed by the server. |
| 413 | Request Entity Too Long | The resource requested by the client to the server is too large and has therefore not been processed. |
| 414 | Request-URI Too Long | The URL sent by the client was so long that the server could no longer process. For example, too many Get parameters. |
| 415 | Unsupported Media Type | The actual type of the resource named in the request and the type of client do not match. |
| 416 | Request range not satisfiable | The area of a document requested could not be delivered by the server. |
| 417 | Expectation failed | The client has an Expect header sent to the server can not fulfill. |
| 424 | Site too ugly | The client has requested a document that the server does not want to deliver. |
HTTP 5xx – Server error
| Code | Meaning | Explanation |
|---|---|---|
| 500 | Internal Server Error | This error is raised when an unexpected error occurred while the server is answering the request. A more detailed reason for the error is found in the server log files. |
| 501 | Not Implemented | The server could not perform the client's request, because he does not support the request. |
| 502 | Bad Gateway | The proxy or gateway has reported that the parent server has supplied incorrect data. |
| 503 | Service Unavailable | The server is temporarily overloaded and can not handle other requests. |
| 504 | Gateway Timeout | The proxy or gateway indicates the fact that the parent server did not provide any data within the expected time period. |
| 505 | HTTP Version Not Supported | The requested HTTP protocol version is not supported by the server. |