Security & Password
X.509 Certificate Viewer
Decode a PEM SSL/TLS certificate: subject, issuer, dates, SANs and fingerprints.
Security & Password
PEM File Decoder
Identify and check every block in a PEM file (certificates, keys, CSRs).
Encrypted private keys are identified but not decrypted.
Good to know
Frequently asked questions
How do I use it?
Enter your pem text and press “Decode”. Check the result, then copy or download it.
How does it work?
Lists each -----BEGIN …----- block, confirms the DER structure is valid, and summarises certificates. Runs in your browser; nothing is uploaded.
Are there limitations?
Encrypted private keys are identified but not decrypted.
Is my data uploaded?
No. Everything is processed in your browser and nothing is sent to a server. No account is needed.
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