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.

12 hosts · 233 ms

HostCertsFirst seenLast seen
rakuten.ne.jp 2 2026-04-24 2026-09-10
*.rakuten.ne.jp 2 2026-04-24 2026-09-10
plaza.rakuten.ne.jp 2 2026-04-29 2026-09-18
*.plaza.rakuten.ne.jp 2 2026-04-29 2026-09-18
book.rakuten.ne.jp 15 2026-03-26 2026-08-21
xml2.toolbar.rakuten.ne.jp 3 2025-09-04 2026-08-17
wizard.toolbar.rakuten.ne.jp 3 2025-09-12 2026-08-20
books.rakuten.ne.jp 15 2026-03-26 2026-08-21
ron.rms.rakuten.ne.jp 4 2025-09-18 2026-08-25
fw.rakuten.ne.jp 1 2026-02-17 2026-02-17
*.fw.rakuten.ne.jp 1 2026-02-17 2026-02-17
www.rakuten.ne.jp 18 2025-08-09 2026-08-21

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