OpsBench

Certificate Transparency Search

Every certificate ever issued for a domain — and the subdomains they reveal.

● Runs on our server
Certificate Transparency logs record every certificate a CA issues. This tool aggregates them and pulls out every hostname that ever appeared on a certificate — a great way to find forgotten subdomains. Primary source is Cert Spotter, with crt.sh (which often falls over) as a fallback. Both are free and key-less.

How it works

Every public certificate is written to Certificate Transparency logs. We query CertSpotter first and fall back to crt.sh, then list each certificate and the hostnames it covers.

Related tools

Let's Encrypt Wizard SSL Checker PEM to PFX CSR Generator