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View All →SSL/TLS Certificate Decoder
Decode and analyze X.509 SSL/TLS certificates. View certificate details, extensions, and certificate chains. Supports all formats.
Decode and inspect SSL/TLS certificates and certificate chains. Upload or paste certificates in any format (PEM, DER, CRT, CER, P7B, P12, PFX, KEY, CSR). View detailed information including subject, issuer, validity period, public key, signature algorithm, extensions (SANs, key usage, basic constraints), and thumbprint. Automatically detects and displays full certificate chains. All processing happens in your browser - your certificates never leave your device. Perfect for security professionals, developers, and system administrators.
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Frequently Asked Questions
What certificate formats can I decode?
The tool supports PEM (.pem, .crt, .cer), DER (.der), PKCS#7 (.p7b), and PKCS#12 (.pfx, .p12) formats. You can paste certificate text directly or upload certificate files for instant decoding.
Can I view the entire certificate chain?
Yes! The decoder displays the complete certificate chain including root CA, intermediate certificates, and end-entity certificates. You can see the trust path and verify each certificate in the chain.
What information is displayed?
View all certificate details: subject/issuer names, validity dates, serial number, public key algorithm, key size, signature algorithm, subject alternative names (SANs), key usage, and extended key usage.
Is it safe to upload my SSL certificates?
Absolutely safe! All certificate decoding happens entirely in your browser using JavaScript. Your certificates never leave your device - no uploads, no server processing, completely private.
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