400
Bad Request
Client ErrorThe server cannot process the request due to a client error such as malformed syntax.
Category: 4xx Client Errors Standard: RFC 9110 First Appeared: HTTP/1.0
What is 400 Bad Request?
HTTP 400 Bad Request is a 4xx status code. The server cannot process the request due to a client error such as malformed syntax.
Client Request
Server
Request Rejected
Common Causes
The request was malformed or invalid
The client lacks permission or valid authentication
The requested resource or route does not exist
A precondition or content requirement was not met
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