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 · 267 ms

HostCertsFirst seenLast seen
dominique.com 17 2026-04-17 2026-08-26
click.dominique.com 1 2026-09-15 2026-09-15
s.dominique.com 1 2026-09-15 2026-09-15
www.dominique.com 7 2026-04-17 2026-08-28

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