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.

4 hosts · 255 ms

HostCertsFirst seenLast seenDNS
charlesifergan.com 6 2026-02-04 2026-09-25 ok
*.charlesifergan.com 1 2026-02-04 2026-02-04 —
news.charlesifergan.com 5 2026-04-29 2026-08-27 ok
www.charlesifergan.com 5 2026-05-28 2026-09-25 ok

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