425 Too Early

The HTTP 425 Too Early client error response status code indicates that the server was unwilling to risk processing a request that might be replayed to avoid potential replay attacks.

If a client has interacted with a server recently, early data (also known as zero round-trip time (0-RTT) data) allows the client to send data to a server in the first round trip of a connection, without waiting for the TLS handshake to complete. A client that sends a request in early data does not need to include the Early-Data header. See {{HTTPHeader("Early-Data")}} for more information.

Status

425 Too Early

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• HTTP response status codes
• TLS
• {{HTTPHeader("Early-Data")}}