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.

10 hosts · 322 ms

HostCertsFirst seenLast seenDNS
rocnation.com 14 2026-04-25 2026-09-28 ok
*.rocnation.com 9 2026-04-26 2026-09-28 —
store.rocnation.com 14 2026-05-11 2026-09-19 ok
distro.rocnation.com 5 2026-05-22 2026-09-20 ok
sso.rocnation.com 7 2026-05-12 2026-09-30 ok
map.rocnation.com 4 2026-06-05 2026-10-03 ok
shop.rocnation.com 6 2026-05-16 2026-09-11 ok
toolkit.rocnation.com 5 2026-04-22 2026-08-26 ok
overview.rocnation.com 5 2026-05-30 2026-09-27 ok
www.rocnation.com 5 2026-04-25 2026-08-23 ok

Programmatic access, with DNS A records: API GET /v1/hosts/rocnation.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/rocnation.com.