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.

4 hosts · 248 ms

HostCertsFirst seenLast seenDNS
aflac-asi.co.jp 1 2026-04-14 2026-04-14 ok
test1.aflac-asi.co.jp 2 2025-09-08 2026-09-03 ok
www.test1.aflac-asi.co.jp 2 2025-09-08 2026-09-03 ok
www.aflac-asi.co.jp 1 2026-04-14 2026-04-14 ok

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