What information does an X.509 certificate contain?
A certificate contains identity details, a public key, validity dates, extensions, issuer information and a cryptographic signature.
Security
Certificate Decoder
Decode PEM or DER X.509 certificates and inspect identity, validity, extensions and fingerprints.
Tool
Certificate Decoder
Decode PEM or DER X.509 certificates and inspect identity, validity, extensions and fingerprints.
This tool runs in your browser. Your input is processed locally and is not uploaded.
About this Tool
Use this certificate decoder to inspect issuer and subject names, serial numbers, validity dates, public key information, subject alternative names, key usage and cryptographic fingerprints.
Examples
- Paste a PEM certificate
- Upload a DER certificate
- Inspect certificate subject alternative names
Frequently Asked Questions
Can the tool confirm that a certificate is trusted?
It can inspect and validate certificate data, but full trust validation also requires a trusted certificate chain and current revocation information.
What is a certificate fingerprint?
A fingerprint is a hash of the encoded certificate used to identify and compare it.
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