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 · 214 ms

HostCertsFirst seenLast seenDNS
kyujinbox.com 1 2025-11-19 2025-11-19 nodata
*.kyujinbox.com 1 2025-11-19 2025-11-19 —
stat-ssl.kyujinbox.com 2 2025-10-12 2025-10-12 ok
vul.kyujinbox.com 1 2025-11-19 2025-11-19 ok
*.vul.kyujinbox.com 1 2025-11-19 2025-11-19 —

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