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 · 353 ms

HostCertsFirst seenLast seenDNS
rudecosmetics.com 14 2026-05-21 2026-10-01 ok
online.rudecosmetics.com 5 2026-07-22 2026-09-20 ok
www.rudecosmetics.com 11 2026-05-21 2026-09-16 ok

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