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.

7 hosts · 372 ms

HostCertsFirst seenLast seenDNS
kigyo.gmo 2 2025-06-25 2026-07-15 ok
stg1.kigyo.gmo 2 2026-06-01 2026-07-07 ok
*.stg1.kigyo.gmo 1 2026-06-01 2026-06-01 —
stg.kigyo.gmo 2 2025-07-27 2026-06-27 nxdomain
api.kigyo.gmo 3 2026-06-24 2026-06-24 ok
column.kigyo.gmo 3 2026-06-13 2026-08-21 ok
www.column.kigyo.gmo 3 2026-06-13 2026-08-21 ok

Programmatic access, with DNS A records: API GET /v1/hosts/kigyo.gmo (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/kigyo.gmo.