Find every subdomain
of a domain.

Every hostname under a domain that ever appeared in a public TLS certificate — with certificate counts, first/last seen and live DNS status.

4 hosts · 326 ms

HostCertsFirst seenLast seenDNS
gmo-cas.com 1 2026-05-07 2026-05-07 ok
kurucasfood.gmo-cas.com 7 2026-05-04 2026-09-19 ok
linktp.gmo-cas.com 5 2026-05-07 2026-09-22 ok
kurucas.gmo-cas.com 5 2026-04-24 2026-09-09 servfail

Programmatic access, with DNS A records: API GET /v1/hosts/gmo-cas.com (API key for paging).

Shown here: hostnames with a certificate that is valid now or expired within the last 90 days. The full history since 2013 — hostnames whose last certificate expired earlier — is a Pro plan method: GET /v1/hosts-history/gmo-cas.com.