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 · 360 ms

HostCertsFirst seenLast seenDNS
email-hayhouse.com 3 2026-02-22 2026-07-20 ok
email.kjbm.email-hayhouse.com 7 2026-04-26 2026-08-24 ok
www.email-hayhouse.com 2 2025-08-07 2026-06-18 ok

Programmatic access, with DNS A records: API GET /v1/hosts/email-hayhouse.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/email-hayhouse.com.