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.

3 hosts · 239 ms

HostCertsFirst seenLast seenDNS
m.email.openbank.es 3 2026-03-12 2026-08-12 ok
res.email.openbank.es 3 2026-03-12 2026-08-12 ok
t.email.openbank.es 3 2026-03-12 2026-08-12 ok

Programmatic access, with DNS A records: API GET /v1/hosts/email.openbank.es (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/email.openbank.es.