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.

3 hosts · 188 ms

HostCertsFirst seenLast seen
kyoto-chushin.jp 1 2025-10-09 2025-10-09
*.kyoto-chushin.jp 1 2025-10-09 2025-10-09
smoothfile.kyoto-chushin.jp 1 2025-11-05 2025-11-05

Programmatic access: API GET /v1/hosts/kyoto-chushin.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/kyoto-chushin.jp.