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.

6 hosts · 323 ms

HostCertsFirst seenLast seenDNS
sundayscaries.com 23 2026-04-12 2026-09-24 ok
*.sundayscaries.com 12 2026-04-12 2026-09-20 —
track.sundayscaries.com 9 2026-06-05 2026-09-01 ok
help.sundayscaries.com 10 2026-05-08 2026-09-03 ok
ss.sundayscaries.com 2 2026-05-02 2026-05-02 ok
www.sundayscaries.com 17 2026-04-14 2026-09-25 ok

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