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 · 353 ms

HostCertsFirst seenLast seenDNS
xtratuf.com 19 2026-05-19 2026-09-29 ok
send.xtratuf.com 8 2026-05-02 2026-06-30 nxdomain
manage.xtratuf.com 6 2026-05-02 2026-06-30 nxdomain
dcsvf.xtratuf.com 9 2026-06-01 2026-09-27 ok
i.xtratuf.com 3 2026-07-08 2026-09-06 ok
sgtm.xtratuf.com 3 2026-05-20 2026-09-04 ok
metrics.xtratuf.com 3 2026-05-11 2026-08-28 ok
pages.xtratuf.com 6 2026-05-03 2026-07-01 nxdomain
www.xtratuf.com 15 2026-05-19 2026-09-29 ok

Programmatic access, with DNS A records: API GET /v1/hosts/xtratuf.com (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/xtratuf.com.