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 · 196 ms

HostCertsFirst seenLast seen
hana-mail.jp 1 2025-12-11 2025-12-11
a8.hana-mail.jp 5 2026-05-23 2026-08-14
mttag.hana-mail.jp 4 2026-04-17 2026-08-15
banner.hana-mail.jp 5 2026-05-20 2026-09-17
fuicmy.hana-mail.jp 2 2026-06-01 2026-08-10

Programmatic access: API GET /v1/hosts/hana-mail.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/hana-mail.jp.