Find every subdomain
of a domain.

Every hostname under a domain that ever appeared in a public TLS certificate — with certificate counts and first/last seen dates.

5 hosts · 250 ms

HostCertsFirst seenLast seen
chanzuckerberg.com 5 2026-05-28 2026-09-29
tech.chanzuckerberg.com 4 2026-04-21 2026-08-23
info.chanzuckerberg.com 12 2026-04-23 2026-08-20
www.chanzuckerberg.com 5 2026-05-28 2026-09-29
apply.chanzuckerberg.com 5 2026-05-25 2026-10-02

Programmatic access: API GET /v1/hosts/chanzuckerberg.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/chanzuckerberg.com.