Web Tools / Browser Tools

X.509 Certificate Parser

Paste a PEM certificate or upload a DER file to inspect subject, issuer, serial number, validity, public key data, extensions, and fingerprints directly in the browser.

Browser only PEM / DER support Local parsing

How this parser works

Drop in a certificate file or paste a PEM block. The parser accepts standard `-----BEGIN CERTIFICATE-----` input, raw base64, or a hexadecimal DER dump.

  • Everything runs locally in your browser
  • Supports paste, drag, and file upload flows
  • Shows subject, issuer, fingerprints, and extensions

Parse a certificate

Choose a file or paste a certificate to inspect it immediately.

Certificates never leave your browser. Parsing happens entirely on the client side.

Certificate Details

Paste a certificate or load the example to inspect it.
SubjectWaiting for input
IssuerWaiting for input
ValidityWaiting for input
SignatureWaiting for input

Core fields

VersionWaiting for input
Serial NumberWaiting for input
Signature AlgorithmWaiting for input
Public Key AlgorithmWaiting for input
Public Key SizeWaiting for input
Certificate LengthWaiting for input

Distinguished Names

SubjectWaiting for input
IssuerWaiting for input

Fingerprints

SHA-1Waiting for input
SHA-256Waiting for input

Extensions

Waiting for input
Ready.