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 · 190 ms

HostCertsFirst seenLast seen
kyushu-fg.co.jp 1 2026-02-25 2026-02-25
hugmeg.kyushu-fg.co.jp 4 2026-04-17 2026-10-09
test.kyushu-fg.co.jp 1 2026-02-16 2026-02-16
www.kyushu-fg.co.jp 2 2026-02-16 2026-02-25

Programmatic access: API GET /v1/hosts/kyushu-fg.co.jp (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/kyushu-fg.co.jp.