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.

7 hosts · 322 ms

HostCertsFirst seenLast seenDNS
cataniaoils.com 11 2026-06-06 2026-10-02 ok
helpdesk.cataniaoils.com 8 2026-06-06 2026-10-04 ok
vpn.cataniaoils.com 4 2026-03-04 2026-08-18 ok
www.vpn.cataniaoils.com 4 2026-03-04 2026-08-18 nxdomain
shop.cataniaoils.com 17 2026-04-19 2026-10-02 ok
cs.cataniaoils.com 12 2026-05-29 2026-09-24 ok
www.cataniaoils.com 10 2026-06-05 2026-10-02 ok

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