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.

4 hosts · 323 ms

Download CSV
HostCertsFirst seenLast seen
cloud.club.myspringfield.com 1 2026-01-30 2026-01-30
image.club.myspringfield.com 3 2026-02-12 2026-09-02
click.club.myspringfield.com 1 2026-01-30 2026-01-30
view.club.myspringfield.com 1 2026-01-30 2026-01-30

Programmatic access: API GET /v1/hosts/club.myspringfield.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/club.myspringfield.com.