SSL Certificate Checker
Analyze SSL/TLS certificates for any domain to verify security configuration and monitor expiration.
When to Use
- Checking SSL certificate expiration dates
- Verifying certificate chain and issuer
- Troubleshooting HTTPS connection issues
- Auditing website security configuration
- Monitoring certificates before renewal
When NOT to Use
- Penetration testing (this is read-only)
- Internal network certificates (use dedicated tools)
- Certificate installation (this only checks, doesn't install)
Examples
Basic Certificate Check
# Check certificate for a domain
openssl s_client -connect example.com:443 -servername example.com </dev/null 2>/dev/null | openssl x509 -noout -dates -subject -issuer
# Get detailed certificate information
echo | openssl s_client -connect example.com:443 -servername example.com 2>/dev/null | openssl x509 -noout -text