SSL Certificate Decoder
Paste a PEM certificate and inspect its subject, issuer, validity, SANs, and fingerprints.
🔒 Certificates are parsed entirely in your browser.
What this tool does
Parses a PEM-encoded X.509 certificate and shows you the human-readable fields: subject, issuer, validity period, public-key algorithm and size, Subject Alternative Names, the SHA-1 and SHA-256 fingerprints, and a list of extensions.
It does notverify the certificate against a trust store or check revocation — it just shows you what's in the file. Powered by @peculiar/x509 in your browser.
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