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
mrfluffyfriend.com 12 2026-05-19 2026-09-29
t.mrfluffyfriend.com 5 2026-04-24 2026-08-22
www.mrfluffyfriend.com 12 2026-05-21 2026-09-29

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