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.

13 hosts · 311 ms

HostCertsFirst seenLast seenDNS
umbraco.dk 33 2026-04-20 2026-10-06 ok
*.umbraco.dk 15 2026-05-13 2026-10-06 —
mail.umbraco.dk 12 2026-04-20 2026-08-16 ok
enterpriseregistration.umbraco.dk 8 2026-04-19 2026-08-15 ok
vpn.umbraco.dk 1 2026-01-06 2026-01-06 ok
www.vpn.umbraco.dk 1 2026-01-06 2026-01-06 nxdomain
sip.umbraco.dk 12 2026-04-20 2026-08-17 ok
mother.umbraco.dk 10 2026-04-19 2026-08-15 ok
lyncdiscover.umbraco.dk 10 2026-04-19 2026-08-15 ok
sites.umbraco.dk 12 2026-04-18 2026-08-14 ok
mta-sts.umbraco.dk 1 2026-01-04 2026-01-04 ok
enterpriseenrollment.umbraco.dk 12 2026-04-19 2026-08-15 ok
www.umbraco.dk 18 2026-04-23 2026-09-09 ok

Programmatic access, with DNS A records: API GET /v1/hosts/umbraco.dk (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/umbraco.dk.