4xx Client Error Responses Subtopics
Explore concepts and entries related to 4xx Client Error Responses.
400 Bad Request
The HTTP 400 Bad Request status code indicates that the server cannot process the request because it is malformed or invalid. Learn how it happens and how to troubleshoot it.
401 Unauthorized
The HTTP 401 Unauthorized status code indicates that authentication is required or has failed. Learn how authentication errors happen and how to troubleshoot them.
403 Forbidden
The HTTP 403 Forbidden status code indicates that the server understands the request but refuses to allow access.
404 Not Found
The HTTP 404 Not Found status code indicates that the server cannot find the requested resource. Learn why 404 errors happen and how to troubleshoot missing resources.
405 Method Not Allowed
The HTTP 405 Method Not Allowed status code indicates that the server understands the request but does not support the HTTP method used.
406 Not Acceptable
The HTTP 406 Not Acceptable status code indicates that the server cannot provide a response matching the formats requested by the client.
407 Proxy Authentication Required
The HTTP 407 Proxy Authentication Required status code indicates that authentication is required with a proxy server.
408 Request Timeout
The HTTP 408 Request Timeout status code indicates that the server timed out waiting for the client request.
409 Conflict
The HTTP 409 Conflict status code indicates that a request conflicts with the current state of the resource.
410 Gone
The HTTP 410 Gone status code indicates that a resource has been permanently removed and is no longer available.
411 Length Required
The HTTP 411 Length Required status code indicates that the server requires a Content-Length header.
412 Precondition Failed
The HTTP 412 Precondition Failed status code indicates that a request condition was not satisfied.
413 Content Too Large
The HTTP 413 Content Too Large status code indicates that the request body is larger than the server allows.
414 URI Too Long
The HTTP 414 URI Too Long status code indicates that the requested URL is longer than the server allows.
415 Unsupported Media Type
The HTTP 415 Unsupported Media Type status code indicates that the server does not support the format of the request data.
416 Range Not Satisfiable
The HTTP 416 Range Not Satisfiable status code indicates that the requested byte range cannot be fulfilled.
417 Expectation Failed
The HTTP 417 Expectation Failed status code indicates that the server cannot meet the requirements specified in the Expect header.
418 I'm a teapot
The HTTP 418 I'm a teapot status code is a humorous response originally created as part of an April Fools RFC.
421 Misdirected Request
The HTTP 421 Misdirected Request status code indicates that the request was sent to a server that cannot produce a response.
422 Unprocessable Content
The HTTP 422 Unprocessable Content status code indicates that the server understands the request but cannot process the supplied data.
423 Locked
The HTTP 423 Locked status code indicates that the requested resource is locked and cannot currently be modified.
424 Failed Dependency
The HTTP 424 Failed Dependency status code indicates that a request failed because another required operation failed.
425 Too Early
The HTTP 425 Too Early status code indicates that a request may be replayed and the server is unwilling to process it yet.
426 Upgrade Required
The HTTP 426 Upgrade Required status code indicates that the client must switch to another protocol.