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Enter a domain to find all SSL certificates logged in Certificate Transparency
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Data sourced from crt.sh — Certificate Transparency log aggregator. Showing up to 200 most recent entries. Deduplicated by common name.
What is Certificate Transparency?
Certificate Transparency (CT) is a public framework that requires CAs to log every certificate they issue into publicly auditable logs. This makes it possible to detect misissued, rogue, or phishing certificates for any domain.
Detect Rogue Certs
If a CA issues a certificate for your domain without your knowledge, it will appear in CT logs. Monitoring lets you catch and report misissuance.
Subdomain Discovery
CT logs reveal subdomains that have had certificates issued — a useful reconnaissance technique for your own domains.
Mandatory Since 2018
Google Chrome has required CT logging for all publicly trusted certificates since April 2018. Every Let's Encrypt certificate is logged.
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This tool queries crt.sh, operated by Sectigo, which aggregates entries from all major CT logs in real time.
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