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.

8 hosts · 398 ms

HostCertsFirst seenLast seenDNS
mcnsrl.it 5 2026-04-26 2026-08-24 ok
mail1.mcnsrl.it 5 2026-05-13 2026-09-11 ok
mail2.mcnsrl.it 4 2026-04-12 2026-08-09 ok
mail3.mcnsrl.it 1 2026-04-17 2026-04-17 ok
bimi.mcnsrl.it 5 2026-04-23 2026-09-14 ok
dnsadm.mcnsrl.it 4 2026-06-07 2026-10-07 ok
mta-sts.mcnsrl.it 4 2026-04-15 2026-08-11 ok
www.mcnsrl.it 5 2026-04-26 2026-08-24 ok

Programmatic access, with DNS A records: API GET /v1/hosts/mcnsrl.it (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/mcnsrl.it.