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.

9 hosts · 248 ms

HostCertsFirst seenLast seen
castlelake.com 3 2025-11-06 2026-10-06
*.castlelake.com 3 2025-11-06 2026-10-06
sysco.castlelake.com 3 2025-08-29 2026-08-30
www.sysco.castlelake.com 3 2025-08-29 2026-08-30
secrets.castlelake.com 1 2026-10-07 2026-10-07
sysco-uat.castlelake.com 1 2026-04-27 2026-04-27
www.sysco-uat.castlelake.com 1 2026-04-27 2026-04-27
market-pulse-fleet.castlelake.com 1 2026-04-27 2026-04-27
www.market-pulse-fleet.castlelake.com 1 2026-04-27 2026-04-27

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