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.

25 hosts · 261 ms

HostCertsFirst seenLast seenDNS
activtrak.com 1 2025-10-27 2025-10-27 ok
*.activtrak.com 42 2026-01-01 2026-10-04 —
insights-ca.activtrak.com 5 2026-05-18 2026-09-21 ok
insights-uk.activtrak.com 4 2026-05-18 2026-09-21 ok
email.activtrak.com 8 2026-05-07 2026-09-02 ok
upflow-email.activtrak.com 5 2026-05-20 2026-09-23 ok
lp.activtrak.com 10 2026-05-06 2026-09-01 ok
data.analytics.activtrak.com 3 2026-05-16 2026-09-05 ok
content.analytics.activtrak.com 3 2026-05-21 2026-09-07 ok
resellers.activtrak.com 1 2025-11-20 2025-11-20 ok
partners.activtrak.com 1 2025-11-20 2025-11-20 ok
developers.activtrak.com 24 2026-04-17 2026-08-16 ok
insights.activtrak.com 3 2026-05-25 2026-09-22 ok
rainuk-insights.activtrak.com 4 2026-05-18 2026-09-21 ok
dev-insights.activtrak.com 4 2026-05-18 2026-09-21 ok
status.activtrak.com 5 2026-04-25 2026-08-22 ok
support.activtrak.com 5 2026-05-25 2026-09-22 ok
test.activtrak.com 10 2026-05-20 2026-09-16 ok
trust.activtrak.com 11 2026-06-06 2026-10-02 ok
insights-au.activtrak.com 4 2026-05-18 2026-09-21 ok
insights-eu.activtrak.com 6 2026-05-18 2026-09-15 ok
wwwdev.activtrak.com 10 2026-05-01 2026-08-27 ok
www.activtrak.com 1 2025-10-27 2025-10-27 ok
survey.activtrak.com 5 2026-05-20 2026-09-17 ok
academy.activtrak.com 2 2026-04-15 2026-09-15 ok

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