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 · 365 ms

HostCertsFirst seenLast seenDNS
marlokids.com 15 2026-05-15 2026-09-24 ok
us.marlokids.com 13 2026-05-20 2026-10-01 ok
www.marlokids.com 17 2026-05-15 2026-09-25 ok

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