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 · 232 ms

HostCertsFirst seenLast seenDNS
valsurf.com 15 2026-04-13 2026-09-27 ok
account.valsurf.com 3 2026-06-10 2026-08-09 ok
www.valsurf.com 15 2026-04-13 2026-09-25 ok
pay.valsurf.com 2 2026-04-28 2026-06-27 ok
www.pay.valsurf.com 2 2026-04-28 2026-06-27 nxdomain

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