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.

9 hosts · 233 ms

HostCertsFirst seenLast seenDNS
listingsproject.com 10 2026-05-12 2026-09-17 ok
*.listingsproject.com 10 2026-05-12 2026-09-17 —
pea.listingsproject.com 2 2026-04-12 2026-04-12 nxdomain
staging.listingsproject.com 2 2026-05-15 2026-05-15 nxdomain
email.listingsproject.com 5 2026-04-29 2026-08-27 ok
join.listingsproject.com 4 2026-06-29 2026-06-29 ok
help.listingsproject.com 5 2026-05-20 2026-09-17 ok
mta-sts.listingsproject.com 5 2026-06-10 2026-09-24 ok
checkout.listingsproject.com 6 2026-04-20 2026-08-16 ok

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