Find every subdomain
of a domain.

Every hostname under a domain that ever appeared in a public TLS certificate — with certificate counts, first/last seen and live DNS status.

8 hosts · 274 ms

HostCertsFirst seenLast seenDNS
planningcenter.com 9 2025-08-11 2026-09-23 ok
*.planningcenter.com 4 2025-08-11 2026-09-09 —
*.staging.planningcenter.com 4 2025-08-11 2026-09-09 —
track.communityupdates.planningcenter.com 3 2026-07-15 2026-09-13 ok
status.planningcenter.com 5 2026-04-30 2026-08-28 ok
support.planningcenter.com 5 2026-05-12 2026-09-09 ok
www.planningcenter.com 5 2026-05-18 2026-09-21 ok
community.planningcenter.com 7 2026-05-30 2026-09-25 ok

Programmatic access, with DNS A records: API GET /v1/hosts/planningcenter.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/planningcenter.com.