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 · 232 ms

HostCertsFirst seenLast seenDNS
athome.co.jp 1 2026-05-21 2026-05-21 ok
*.athome.co.jp 2 2026-05-19 2026-05-21 —
stg.atbb.athome.co.jp 1 2026-05-18 2026-05-18 ok
zmn.atbb.athome.co.jp 1 2026-05-19 2026-05-19 ok
stg.hikkoshi.athome.co.jp 1 2026-05-19 2026-05-19 ok
team.athome.co.jp 1 2026-05-19 2026-05-19 ok
loan-simulator.athome.co.jp 1 2026-05-18 2026-05-18 ok

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