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 · 334 ms

HostCertsFirst seenLast seenDNS
staybloom.com 5 2026-05-04 2026-10-04 ok
*.staybloom.com 10 2026-02-02 2026-10-04 —
elinks.staybloom.com 8 2026-05-31 2026-10-03 ok

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