SSL Certificate & Key Checker

Check whether a certificate matches its private key and inspect validity, expiry, SANs, issuer, algorithm, and public-key fingerprint. Supports ECC, RSA, and other common key types.

Everything is processed locally in your browser. Nothing is uploaded or stored.

Certificate .crt · .pem

Paste text or drop a .crt / .pem file
No certificate selected

Private Key .key · .pem

Paste text or drop a .key / .pem file
No private key selected
Supports ECC (P-256, P-384, P-521), RSA, and other common PEM key formats.
Provide a certificate and private key above. The result will appear here automatically.
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