Certificate Validator & Key Matcher

Drop a .pfx/.p12, .pem, .crt/.cer/.der, .csr or private key — or several at once — and get key ↔ certificate ↔ CSR matching (RSA modulus / public-key), expiry, chain, key strength, EKU/SAN, and Active-Directory attack context (PKINIT, Smart-Card-Logon, ESC1-style UPN SANs). Everything runs in your browser with an inlined crypto engine — no network, nothing stored, works air-gapped.