Find every subdomain
of a domain.

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

4 hosts · 291 ms

HostCertsFirst seenLast seen
thesaschool.com 2 2026-06-08 2026-06-14
*.thesaschool.com 1 2026-06-08 2026-06-08
forms.thesaschool.com 5 2026-06-01 2026-09-29
www.thesaschool.com 1 2026-06-14 2026-06-14

Programmatic access: API GET /v1/hosts/thesaschool.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/thesaschool.com.