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.

5 hosts · 286 ms

HostCertsFirst seenLast seenDNS
dathost.net 24 2026-04-30 2026-09-23 ok
*.dathost.net 24 2026-04-30 2026-09-23 —
cms-staging.dathost.net 12 2026-04-27 2026-08-23 ok
help.dathost.net 5 2026-04-28 2026-08-26 ok
cms.dathost.net 8 2026-04-24 2026-08-21 ok

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