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.

4 hosts · 290 ms

HostCertsFirst seenLast seenDNS
divenewsletter.com 16 2026-05-26 2026-09-22 ok
*.divenewsletter.com 16 2026-05-26 2026-09-22 —
link.divenewsletter.com 2 2026-07-14 2026-07-14 ok
link-dev.divenewsletter.com 2 2026-07-14 2026-07-14 ok

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