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.

3 hosts · 263 ms

HostCertsFirst seenLast seen
sp7.com 16 2026-05-07 2026-09-16
account.sp7.com 13 2026-04-28 2026-09-07
www.sp7.com 18 2026-04-22 2026-09-01

Programmatic access: API GET /v1/hosts/sp7.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/sp7.com.