PublicDNS Tools

What it does

  • Connects to hostname:443 over TLS
  • Reads the leaf certificate and its expiry
  • Fetches and parses the certificate chain
  • Shows protocol (e.g. TLS 1.2 / 1.3) and cipher
  • Displays SAN entries and SHA-256 fingerprint

Typical use cases

  • Check when a certificate will expire
  • Verify which CA issued the certificate
  • Confirm the hostname/SAN is correct
  • See which TLS version and cipher are negotiated

Notes

This tool does not replace a full SSL test or vulnerability scanner. It is intended as a quick overview. OCSP/CRL status and advanced configuration checks are out of scope.