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.

4 hosts · 376 ms

HostCertsFirst seenLast seenDNS
cloud.message.auspost.com.au 1 2026-07-15 2026-07-15 ok
image.message.auspost.com.au 3 2026-07-15 2026-09-02 ok
click.message.auspost.com.au 1 2026-07-15 2026-07-15 ok
view.message.auspost.com.au 1 2026-07-15 2026-07-15 ok

Programmatic access, with DNS A records: API GET /v1/hosts/message.auspost.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/message.auspost.com.au.