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 · 167 ms

HostCertsFirst seenLast seen
finfi.co 9 2025-11-07 2026-10-09
*.finfi.co 1 2025-11-07 2025-11-07
www.finfi.co 11 2026-06-13 2026-10-09

Programmatic access: API GET /v1/hosts/finfi.co (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/finfi.co.