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.

3 hosts · 308 ms

HostCertsFirst seenLast seen
coastr.com.au 3 2026-03-11 2026-09-14
app.coastr.com.au 14 2026-05-06 2026-09-01
www.coastr.com.au 4 2026-02-14 2026-09-29

Programmatic access: API GET /v1/hosts/coastr.com.au (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/coastr.com.au.