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.

21 hosts · 296 ms

HostCertsFirst seenLast seenDNS
efexchangeyear.org 166 2026-05-05 2026-10-03 ok
*.efexchangeyear.org 9 2026-05-24 2026-09-27 —
qa2.efexchangeyear.org 20 2026-05-05 2026-09-02 nxdomain
iec-qa2.efexchangeyear.org 18 2026-05-05 2026-09-02 nxdomain
host-qa2.efexchangeyear.org 20 2026-05-05 2026-09-02 nxdomain
qa.efexchangeyear.org 18 2026-05-05 2026-09-07 ok
iec-qa.efexchangeyear.org 18 2026-05-05 2026-09-07 nxdomain
host-qa.efexchangeyear.org 16 2026-05-05 2026-09-07 ok
iec.efexchangeyear.org 6 2026-05-12 2026-09-07 nxdomain
hsey-dt-api.efexchangeyear.org 1 2025-09-24 2025-09-24 ok
www.hsey-dt-api.efexchangeyear.org 1 2025-09-24 2025-09-24 nxdomain
login.efexchangeyear.org 4 2026-04-12 2026-08-24 ok
leader.efexchangeyear.org 2 2026-05-01 2026-05-01 ok
discoverytours.efexchangeyear.org 13 2026-05-15 2026-09-10 ok
host.efexchangeyear.org 14 2026-05-12 2026-10-03 ok
qa.host.efexchangeyear.org 20 2026-05-09 2026-09-04 nxdomain
logindev.efexchangeyear.org 4 2026-04-13 2026-08-25 ok
hsey.efexchangeyear.org 5 2026-05-11 2026-09-15 ok
dev-hsey.efexchangeyear.org 4 2026-04-15 2026-08-14 ok
my.efexchangeyear.org 5 2026-05-21 2026-09-22 ok
staging-my.efexchangeyear.org 6 2026-05-28 2026-09-30 ok

Programmatic access, with DNS A records: API GET /v1/hosts/efexchangeyear.org (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/efexchangeyear.org.