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 · 243 ms

HostCertsFirst seenLast seenDNS
tsubaki.net.vn 3 2026-03-17 2026-09-25 ok
store.tsubaki.net.vn 1 2026-09-01 2026-09-01 ok
www.store.tsubaki.net.vn 1 2026-09-01 2026-09-01 nxdomain
en.tsubaki.net.vn 3 2026-03-16 2026-09-25 ok
www.en.tsubaki.net.vn 3 2026-03-16 2026-09-25 ok
mta-sts.tsubaki.net.vn 5 2026-05-05 2026-09-02 ok
dev.tsubaki.net.vn 4 2026-05-05 2026-07-04 ok
www.dev.tsubaki.net.vn 4 2026-05-05 2026-07-04 ok
www.tsubaki.net.vn 3 2026-03-17 2026-09-25 ok

Programmatic access, with DNS A records: API GET /v1/hosts/tsubaki.net.vn (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/tsubaki.net.vn.