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.

10 hosts · 218 ms

HostCertsFirst seenLast seen
xserver.ne.jp 2 2026-06-02 2026-06-04
*.xserver.ne.jp 2 2026-06-02 2026-06-04
secure.xserver.ne.jp 3 2025-10-06 2026-09-16
a8-xshop.secure.xserver.ne.jp 7 2026-05-09 2026-09-05
www.secure.xserver.ne.jp 3 2025-10-06 2026-09-16
a8clk.xserver.ne.jp 7 2026-05-18 2026-09-14
webmail.xserver.ne.jp 2 2026-06-02 2026-06-04
www.webmail.xserver.ne.jp 2 2026-06-02 2026-06-04
registrar.xserver.ne.jp 3 2026-04-10 2026-09-15
www.registrar.xserver.ne.jp 3 2026-04-10 2026-09-15

Programmatic access: API GET /v1/hosts/xserver.ne.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/xserver.ne.jp.