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 · 320 ms

HostCertsFirst seenLast seenDNS
air4casts.com 9 2025-09-20 2026-08-08 ok
*.air4casts.com 8 2025-09-22 2026-08-08 —
link.air4casts.com 5 2026-05-12 2026-09-09 ok
help.air4casts.com 5 2026-04-30 2026-08-28 ok
www.air4casts.com 1 2025-09-20 2025-09-20 ok

Programmatic access, with DNS A records: API GET /v1/hosts/air4casts.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/air4casts.com.