Find every subdomain
of a domain.

Every hostname under a domain that ever appeared in a public TLS certificate — with certificate counts, first/last seen and live DNS status.

8 hosts · 286 ms

HostCertsFirst seenLast seenDNS
gmo-c.jp 2 2025-06-11 2026-07-08 ok
oar.gmo-c.jp 2 2026-05-17 2026-05-17 ok
*.oar.gmo-c.jp 2 2026-05-17 2026-05-17 —
stg.oar.gmo-c.jp 4 2026-08-24 2026-08-24 ok
*.stg.oar.gmo-c.jp 4 2026-08-24 2026-08-24 —
dev.oar.gmo-c.jp 4 2026-08-25 2026-08-25 ok
*.dev.oar.gmo-c.jp 4 2026-08-25 2026-08-25 —
www.gmo-c.jp 2 2025-06-11 2026-07-08 ok

Programmatic access, with DNS A records: API GET /v1/hosts/gmo-c.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/gmo-c.jp.