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 · 313 ms

HostCertsFirst seenLast seenDNS
egcu.org 8 2026-05-06 2026-09-01 ok
merchant.egcu.org 4 2026-02-06 2026-09-21 ok
www.egcu.org 10 2026-05-06 2026-09-01 ok

Programmatic access, with DNS A records: API GET /v1/hosts/egcu.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/egcu.org.