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.

14 hosts · 272 ms

HostCertsFirst seenLast seenDNS
originalpenguin.com 10 2026-05-17 2026-09-22 ok
wd.originalpenguin.com 10 2026-04-24 2026-08-20 ok
trk.e.originalpenguin.com 10 2026-06-03 2026-09-29 ok
sms.e.originalpenguin.com 8 2026-05-15 2026-09-10 ok
ss3.zone.originalpenguin.com 3 2026-07-20 2026-09-18 ok
beanoriginal.originalpenguin.com 7 2026-05-08 2026-08-31 ok
email.originalpenguin.com 7 2026-05-08 2026-08-31 ok
m.originalpenguin.com 7 2026-05-08 2026-08-31 ok
licensees.originalpenguin.com 3 2026-05-05 2026-08-18 ok
lt-links.originalpenguin.com 8 2026-04-20 2026-08-16 ok
returns.originalpenguin.com 6 2026-05-16 2026-09-11 ok
account.originalpenguin.com 17 2026-04-18 2026-09-30 ok
support.originalpenguin.com 3 2026-04-29 2026-09-29 ok
www.originalpenguin.com 18 2026-05-17 2026-09-27 ok

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