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 · 297 ms

HostCertsFirst seenLast seenDNS
e.newyorktimes.com 5 2026-04-30 2026-09-09 ok
l.email.newyorktimes.com 3 2026-05-25 2026-09-10 ok
em.newyorktimes.com 5 2026-05-03 2026-09-12 ok
emergency.newyorktimes.com 2 2026-01-31 2026-06-16 ok

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