Discover subdomains using Certificate Transparency logs
Free & No API Key Required: This tool uses public Certificate Transparency logs from crt.sh. Completely free, no registration needed!
Searching Certificate Transparency logs...
Certificate Transparency logs are public records of SSL/TLS certificates issued for domains. When a certificate is issued, it's logged in these public databases. This tool queries crt.sh, which aggregates these logs to help you discover subdomains.
Yes! This tool uses only publicly available Certificate Transparency data. It's a legitimate OSINT technique used by security researchers and penetration testers for reconnaissance and subdomain enumeration.
Subdomains only appear in CT logs if they have valid SSL certificates. Subdomains without certificates won't be discovered. Also, older certificates may have expired and been removed from logs.
Yes! This is a common reconnaissance technique in penetration testing and security research. Always ensure you have proper authorization before conducting any security assessments.
Yes! HackHint's Subdomain Finder is completely free with no registration required. You can check unlimited domains without any restrictions.