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.

4 hosts · 227 ms

HostCertsFirst seenLast seen
nehii.org 7 2026-04-27 2026-08-25
*.nehii.org 2 2026-03-30 2026-08-30
support.nehii.org 2 2026-01-26 2026-06-23
www.nehii.org 7 2026-04-27 2026-08-25

Programmatic access: API GET /v1/hosts/nehii.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/nehii.org.