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.

9 hosts · 267 ms

HostCertsFirst seenLast seenDNS
fincode.jp 1 2025-10-16 2025-10-16 ok
*.fincode.jp 1 2025-10-16 2025-10-16 —
*.dev2.fincode.jp 4 2025-08-07 2026-07-10 —
blog.fincode.jp 2 2025-08-10 2026-09-08 ok
form.fincode.jp 4 2026-04-17 2026-08-15 ok
support.fincode.jp 4 2026-01-26 2026-09-30 ok
test.fincode.jp 1 2025-10-16 2025-10-16 nodata
*.test.fincode.jp 1 2025-10-16 2025-10-16 —
*.dev.fincode.jp 4 2025-08-09 2026-07-11 —

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