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.

6 hosts · 303 ms

HostCertsFirst seenLast seenDNS
plmcorp.net 12 2026-05-23 2026-09-19 ok
email.send.plmcorp.net 5 2026-05-09 2026-09-06 ok
payments.plmcorp.net 4 2026-03-31 2026-08-26 ok
www.payments.plmcorp.net 4 2026-03-31 2026-08-26 ok
mta-sts.plmcorp.net 3 2026-05-24 2026-08-15 ok
www.plmcorp.net 7 2026-05-23 2026-09-18 ok

Programmatic access, with DNS A records: API GET /v1/hosts/plmcorp.net (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/plmcorp.net.