SSL Certificate Decoder
Paste a PEM SSL certificate and decode it to see subject, issuer, validity dates, Subject Alternative Names, and key type. Client-side decoding.
Used 19.0K times today
How to Use SSL Certificate Decoder
- 1
Paste your PEM certificate
Copy your certificate including the BEGIN CERTIFICATE and END CERTIFICATE lines and paste it into the input.
- 2
Click Decode
The tool parses the certificate and extracts all key fields.
- 3
Review the certificate details
See the subject, issuer, validity period, SANs, and public key algorithm.
Frequently Asked Questions
What is a PEM certificate?
Is my certificate data private?
Embed This Tool
Add this tool to your website for free. Just copy and paste the code below:
<iframe src="https://utilko.com/embed/ssl-certificate-decoder/" width="100%" height="500" frameborder="0" title="SSL Certificate Decoder"></iframe> About SSL Certificate Decoder
The SSL Certificate Decoder on Utilko parses PEM-format X.509 certificates in your browser and displays the subject, issuer, expiry date, and Subject Alternative Names in human-readable form — no server required.
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