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ToolsSSL / TLSCertificate Decoder
SSL / TLS

Certificate Decoder

Paste a PEM-encoded certificate to reveal its subject, issuer, validity and extensions.

Enter a value above and run the check to see results here.

How it works

Paste a PEM-encoded certificate to reveal its subject, issuer, validity and extensions.

Related tools

SSL CheckerSSL Expiry Checker

Frequently asked questions

Is the Certificate Decoder tool free to use?+

Yes. The Certificate Decoder runs directly in NetInsight with no signup required. Usage is rate limited per IP address to keep the service fast for everyone.

Are my queries logged?+

Diagnostic inputs are processed to produce your result and are not sold or shared. See our Privacy Policy for full detail on retention.

How accurate are the Certificate Decoder results?+

Results are fetched live from authoritative sources each time you run a check, so they reflect the current state rather than a cached snapshot.

More SSL / TLS tools

SSL / TLS

SSL Checker

Validate a site's certificate and chain.

SSL / TLS

SSL Expiry Checker

Count the days left on a certificate.