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 · 186 ms

HostCertsFirst seenLast seen
kyushu-fg-sec.co.jp 5 2025-10-22 2026-08-06
onlinetrade.kyushu-fg-sec.co.jp 2 2026-02-12 2026-02-12
cts.kyushu-fg-sec.co.jp 2 2026-02-12 2026-02-12
test.kyushu-fg-sec.co.jp 6 2025-10-22 2026-08-06
www.kyushu-fg-sec.co.jp 6 2025-10-22 2026-08-06

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