Precondition Failed
HTTP 412 Precondition Failed is a Client errors (4xx) status code. One of the conditions in the request headers was not met.
What 412 means
One of the conditions in the request headers was not met.
Used with conditional headers like If-Match to prevent lost updates when a resource changed since it was fetched.
Client errors (4xx)
The request contains an error from the client — bad syntax, missing auth or a wrong URL.
Other 4xx codes
FAQ — 412
What does HTTP 412 mean?
412 Precondition Failed: One of the conditions in the request headers was not met. Used with conditional headers like If-Match to prevent lost updates when a resource changed since it was fetched.
Which class does status code 412 belong to?
412 is a Client errors (4xx) code. The request contains an error from the client — bad syntax, missing auth or a wrong URL.
Where is the 412 code defined?
Status code 412 is defined in RFC 9110 and is part of the IANA HTTP Status Code Registry.