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.

13 hosts · 280 ms

HostCertsFirst seenLast seenDNS
aeonssi.co.jp 2 2025-07-15 2026-07-31 nodata
iembed.aeonssi.co.jp 3 2025-07-22 2026-08-04 ok
org-iembed.aeonssi.co.jp 2 2025-06-10 2026-05-11 ok
stg-iembed.aeonssi.co.jp 3 2025-07-22 2026-08-04 ok
org-stg-iembed.aeonssi.co.jp 2 2025-06-30 2026-05-31 ok
kikan.aeonssi.co.jp 2 2025-07-25 2026-08-10 ok
test-kikan.aeonssi.co.jp 4 2026-04-27 2026-07-17 ok
help.aeonssi.co.jp 5 2026-05-26 2026-09-24 ok
keiyaku.aeonssi.co.jp 3 2025-07-25 2026-08-10 ok
test-keiyaku.aeonssi.co.jp 3 2026-03-13 2026-09-11 ok
www.aeonssi.co.jp 2 2025-07-15 2026-07-31 ok
test-www.aeonssi.co.jp 1 2025-12-12 2025-12-12 ok
www.test-www.aeonssi.co.jp 1 2025-12-12 2025-12-12 nxdomain

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