Find every subdomain
of a domain.

Every hostname under a domain that ever appeared in a public TLS certificate — with certificate counts and first/last seen dates.

8 hosts · 220 ms

HostCertsFirst seenLast seen
northmill.no 2 2026-03-30 2026-08-30
klick.northmill.no 15 2026-05-19 2026-09-17
n.northmill.no 5 2026-05-07 2026-09-04
mta-sts.info.northmill.no 1 2025-11-17 2025-11-17
mta-sts.northmill.no 2 2025-10-12 2026-09-12
mta-sts.news.northmill.no 1 2025-11-18 2025-11-18
support.northmill.no 2 2026-04-06 2026-09-06
www.northmill.no 2 2026-03-30 2026-08-30

Programmatic access: API GET /v1/hosts/northmill.no (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/northmill.no.