428

Precondition Required

Client Error

RFC 6585

The origin server requires the request to be conditional.

Detailed Information

The 428 status code indicates that the origin server requires the request to be conditional. This is often returned when a client attempts to access a resource that requires authentication or other preconditions.

Common Examples

API requests with missing If-Match headers
Form submissions with missing If-Unmodified-Since headers

Common Uses

API requests with missing If-Match headers
Form submissions with missing If-Unmodified-Since headers

Best Practices

Use when the request requires a precondition
Include appropriate precondition headers
Ensure proper resource versioning and conflict resolution mechanisms are in place