What are the HTTP status code 4XX?


All status code that begins with the number 4 are error code.

Meaning that an error has occurred during the request and that the server may use any of this code to send feedback about bad request parameters for instance.

The specification calls this type of error error caused by the client and makes a distinction with the error of the server that is classified with a 5XX number.


Code Description
400 Bad Request
401 Unauthorized
402 Payment Required
403 Forbidden
404 Not Found
405 Method Not Allowed
406 Not Acceptable (send for instance when the requested media type cannot be send)
407 Proxy Authentication Required
408 Request Timeout
409 Conflict
410 Gone
411 Length Required
412 Precondition Failed
413 Request Entity Too Large
414 Request-URI Too Long
415 Unsupported Media Type
416 Requested Range Not Satisfiable
417 Expectation Failed
422 Unprocessable Entity (The client should not repeat this request without modification.)
444 A non-standard status code used to instruct nginx to close the connection without sending a response to the client, most commonly used to deny malicious or malformed requests. - This status code is not seen by the client, it only appears in nginx log files. (you may also send a 503 (Service Temporarily Unavailable))

Documentation / Reference

Discover More
HTTP - Accept header

accept is a request header that specify the mimes type of the response body that are accepted by the client (ie browser) If no Accept header field is present, then it is assumed that the client accepts...
HTTP - Accept-Encoding

accept-encoding is a request header that lists the encoding format that the client can read. With a get request Example of values where the value tells the content coding what the client will accept...
HTTP - Status Code

The status code is the exit code of request returned to the client via the first line of a response. For example: a file not found error is a 404 code, a server error is equivalent to a 5xx code....
400 Default Page No Required Ssl Certificate
How to configure certification based client authentication with Nginx ?

This article shows you how to configure a client authentication via the ownership of a certificat on a Nginx web server. The server should be already configured for HTTPS as client certificate (client...
Web HTTP - 404 Error (Resource not found)

The 404 error is a error (4xx) return status of a request that means that the client has asked a resource that was not found (equivalent to a file not found for a file system). This is the most common...
Web HTTP - SameSite Cookie property (First-Party-Only)

samesite is a cookie property that controls if a cookie should be sent along in a cross-site HTTP request ie: when the origin of the code (HTML, Javascript, ..) that created the request (generally the...
Ovh Virtual Hosting Subdomain
What is and how works a virtual host / custom domain / vanity hostnames

This article gives you an overview on how and where virtual hosting / custom domain is implemented.
Soap Ui Basic Authentication
What is and how works the Basic Authentication scheme? (HTTP)

Basic Access Authentication is an Authentication mechanism for HTTP request. To be authenticated, the request should have: the header authorization and its value should have this format: the basic...

Share this page:
Follow us:
Task Runner