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.

10 hosts · 240 ms

HostCertsFirst seenLast seenDNS
banq.hamagin.co.jp 2 2026-08-13 2026-08-13 ok
dev.banq.hamagin.co.jp 2 2026-07-31 2026-07-31 ok
web.hamapengpt.hamagin.co.jp 3 2026-02-21 2026-10-05 ok
dev-web.hamapengpt.hamagin.co.jp 4 2026-02-22 2026-10-06 ok
api.hamapengpt.hamagin.co.jp 4 2026-02-21 2026-10-05 ok
dev-api.hamapengpt.hamagin.co.jp 4 2026-02-22 2026-10-06 ok
prod.dify.hamagin.co.jp 2 2026-08-30 2026-08-30 nodata
*.prod.dify.hamagin.co.jp 2 2026-08-30 2026-08-30 —
dev.dify.hamagin.co.jp 6 2026-08-27 2026-08-27 nodata
*.dev.dify.hamagin.co.jp 6 2026-08-27 2026-08-27 —

Programmatic access, with DNS A records: API GET /v1/hosts/hamagin.co.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/hamagin.co.jp.