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.

3 hosts · 311 ms

HostCertsFirst seenLast seenDNS
communitas.com 5 2026-05-15 2026-08-19 ok
mta-sts.communitas.com 2 2026-09-03 2026-09-03 ok
www.communitas.com 5 2026-05-15 2026-08-19 ok

Programmatic access, with DNS A records: API GET /v1/hosts/communitas.com (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/communitas.com.