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 · 235 ms

HostCertsFirst seenLast seenDNS
*.email.cc.yahoo.com 18 2026-05-18 2026-09-29 —
ca.email.cc.yahoo.com 2 2026-03-25 2026-08-19 ok
e.email.cc.yahoo.com 2 2026-03-25 2026-08-19 ok
images.email.cc.yahoo.com 2 2026-03-25 2026-08-19 ok
view.email.cc.yahoo.com 2 2026-03-25 2026-08-19 ok

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