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.

17 hosts · 239 ms

HostCertsFirst seenLast seenDNS
traindems.org 18 2026-04-17 2026-10-04 ok
*.traindems.org 14 2026-05-07 2026-10-04 —
dbproxy-ndtc-profile-gamma2.traindems.org 1 2026-01-14 2026-01-14 nxdomain
dbproxy-ndtc-content-gamma2.traindems.org 1 2026-01-14 2026-01-14 nxdomain
media.traindems.org 5 2026-04-26 2026-08-24 ok
dbproxy-ndtc-profile-gamma.traindems.org 3 2026-01-14 2026-01-14 nxdomain
dbproxy-ndtc-content-gamma.traindems.org 3 2026-01-14 2026-01-14 nxdomain
dbproxy-ndtc-profile.traindems.org 2 2025-08-21 2026-01-13 nxdomain
staging.traindems.org 4 2026-04-16 2026-08-21 ok
auth.traindems.org 3 2025-08-27 2026-07-28 ok
learn.traindems.org 2 2025-08-08 2026-07-10 ok
preferences.traindems.org 5 2026-05-18 2026-09-15 ok
courses.traindems.org 1 2026-06-17 2026-06-17 ok
programs.traindems.org 5 2026-04-26 2026-08-24 ok
dbproxy-ndtc-content.traindems.org 2 2025-08-21 2026-01-13 nxdomain
www.traindems.org 4 2026-04-11 2026-08-12 ok
community.traindems.org 7 2026-05-30 2026-09-25 ok

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