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 · 317 ms

HostCertsFirst seenLast seenDNS
marks-clerk.ca 5 2026-05-15 2026-09-11 ok
remote.marks-clerk.ca 3 2025-07-22 2026-07-16 ok
link.marks-clerk.ca 5 2026-04-26 2026-08-24 ok
www.marks-clerk.ca 5 2026-05-15 2026-09-11 ok

Programmatic access, with DNS A records: API GET /v1/hosts/marks-clerk.ca (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/marks-clerk.ca.