Classical public-key cryptography (RSA, ECDSA, ECDH) breaks against a sufficiently large quantum computer. That computer doesn't exist yet. The encrypted traffic attackers are recording today, though, will still be valuable when it does. The defense is TLS 1.3 with a post-quantum hybrid key exchange, which most browsers now negotiate if the server offers it. This tool probes your server for PQC hybrid-KEX support, inspects the certificate chain, and emits a migration plan aligned to the NSM-10 / CNSA 2.0 federal deadlines. See the walkthrough for why this matters. Related: Modern security headers (the HTTP-layer complement) · Mega Security Analyzer (seven-layer combined scan) · How the TLS probe works.