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.

10 hosts · 252 ms

Download CSV
HostCertsFirst seenLast seen
one.fit 13 2026-05-22 2026-10-03
*.one.fit 13 2026-05-22 2026-10-03
lemtrail.one.fit 5 2026-05-13 2026-09-11
help.one.fit 5 2026-05-09 2026-09-06
gtmserver.one.fit 3 2026-05-29 2026-09-12
web-assets.one.fit 4 2026-05-30 2026-09-16
partner-assets.one.fit 3 2026-05-21 2026-09-05
events.one.fit 14 2026-04-29 2026-08-25
sandbox.one.fit 4 2026-06-14 2026-06-14
*.sandbox.one.fit 4 2026-06-14 2026-06-14

Programmatic access: API GET /v1/hosts/one.fit (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/one.fit.