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 · 307 ms

HostCertsFirst seenLast seenDNS
dtsearch.com 3 2025-11-03 2025-11-27 ok
*.dtsearch.com 3 2025-07-26 2026-06-26 —
search.dtsearch.com 5 2026-06-03 2026-10-06 ok
www.dtsearch.com 1 2025-11-03 2025-11-03 ok

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