Decode an SSL/TLS Certificate Online

Decode SSL certificates from websites or paste certificate data directly. Our tool parses X.509 certificates and displays comprehensive information including validity dates, issuer details, subject information, and security properties.

❓ Frequently Asked Questions About Certificate Decoding

A certificate decoder is an online tool that extracts and displays details from SSL/TLS or X.509 certificates. It allows you to see the subject, issuer, validity dates, public keys, and extensions in a human-readable format.

Our tool supports PEM, CRT, CER, X.509, and CSR files, helping developers, sysadmins, and security professionals verify certificates quickly and easily.

You simply paste or upload your SSL/TLS certificate (PEM, CRT, CER, X.509, or CSR). The tool parses its contents and displays structured information such as the subject, issuer, expiration date, fingerprints, and extensions.

No data is stored. Everything is processed securely in your browser to keep your certificates private.

Decoding certificates helps you troubleshoot SSL errors, confirm certificate chains, verify the issuer and validity dates, or ensure a CSR (Certificate Signing Request) is correct before submission.

It’s essential for web admins, developers, and anyone managing HTTPS, VPNs, or secure services.

The tool supports the most common certificate formats, including:

• PEM (.pem, .crt, .cer)
• X.509 certificates
• DER encoded certificates
• CSR (Certificate Signing Request)

This ensures compatibility with web servers, VPNs, and certificate authorities.

Yes. Our decoder runs securely in your browser, no certificate data is uploaded or stored. This guarantees privacy when inspecting SSL/TLS certificates or CSRs.

For sensitive certificates (like private keys, which you should never share), only upload the public certificate or CSR, not your private key.

Decoded certificates typically show:

• Subject (who the certificate was issued to)
• Issuer (the Certificate Authority)
• Validity period (start and expiration dates)
• Public key algorithm and size
• Fingerprints (SHA-1, SHA-256)
• Extensions (SANs, key usage, policies, etc.)

This information helps verify trust and troubleshoot SSL/TLS issues.

MyIP.casa’s free Certificate Decoder makes it easy to analyze SSL/TLS and X.509 certificates directly in your browser. Ideal for checking expiration dates, verifying issuers, and reviewing CSR details.

No signup required, just paste your certificate and instantly view structured results. Combine it with our IP Lookup or Latency Test tools for complete network diagnostics.