Is Certificate Decoder free to use?

Yes, Certificate Decoder on DevHexLab is completely free. No login, no account, and no payment required.

Does Certificate Decoder upload my data to a server?

No. Certificate Decoder runs entirely in your browser using client-side JavaScript. Your data never leaves your device and is never sent to any server.

Can I use Certificate Decoder offline?

Yes. Once the page is loaded, Certificate Decoder works without an internet connection because all processing happens locally in your browser.

What category does Certificate Decoder belong to?

Certificate Decoder belongs to the "Security" category on DevHexLab. Generate cryptographically strong passwords, test password strength against common patterns, and compute MD5, SHA-1, SHA-256, and other hashes from any input. Everything runs client-side so sensitive data never leaves your machine.

Certificate Decoder

Paste a PEM certificate and decode its fields — subject, issuer, validity dates, SANs, and key usage

ssltlscertificatepemx509

PEM Certificate

Certificate Decoder is coming soon

This tool is actively being built and will be available shortly. All other tools on DevHexLab are free and ready to use now.

Check back soon

Learn more

Step-by-step guide

How to Decode an SSL/TLS Certificate

Learn how to read and verify the contents of a PEM-encoded SSL/TLS certificate using the Certificate Decoder.

In-depth article

Decoding SSL Certificates for Debugging

When a TLS handshake fails or a browser shows a certificate warning, decoding the certificate is the fastest path to understanding what went wrong.

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