Is the private key inspected?

No — public certificates only. Don't paste private keys into any web tool.

Why does the sample fail?

It's a placeholder; replace with a real cert. We don't ship a working sample to avoid giving the impression of a 'real' identity.

SSL Certificate Decoder

Paste a PEM-encoded SSL/TLS certificate to inspect issuer, subject, SANs, validity period, public key, and signature algorithm. Everything runs in your browser — no certificate is uploaded.

PEM certificate

How to use the ssl certificate decoder

Paste a PEM-encoded X.509 certificate (begins with -----BEGIN CERTIFICATE-----). Click Decode to view the subject, issuer, validity period, SAN list, and signature algorithm.

Formula & explanation

Examples

Paste a server cert from openssl s_client, a CA bundle item, or a self-signed development cert.

Frequently asked questions

Is the private key inspected?: No — public certificates only. Don't paste private keys into any web tool.
Why does the sample fail?: It's a placeholder; replace with a real cert. We don't ship a working sample to avoid giving the impression of a 'real' identity.

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