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.

7 hosts · 254 ms

HostCertsFirst seenLast seenDNS
bluejackets.com 17 2026-05-11 2026-09-22 ok
*.bluejackets.com 17 2026-05-11 2026-09-22 —
remote.bluejackets.com 5 2026-05-01 2026-08-29 ok
cr.bluejackets.com 5 2026-05-30 2026-09-30 ok
pr.bluejackets.com 6 2026-06-15 2026-08-13 ok
cert.bluejackets.com 5 2026-05-03 2026-08-31 ok
communityreport.bluejackets.com 5 2026-05-01 2026-08-31 ok

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