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.

5 hosts · 281 ms

HostCertsFirst seenLast seenDNS
beginjob.com 4 2026-04-19 2026-08-17 ok
*.beginjob.com 4 2026-04-19 2026-08-17 —
*.resource.beginjob.com 4 2026-04-19 2026-08-17 —
trk.resource.beginjob.com 3 2025-09-08 2025-09-08 ok
jobresults.beginjob.com 3 2026-06-12 2026-09-01 ok

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