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 · 344 ms

HostCertsFirst seenLast seenDNS
synclature.com 15 2026-05-15 2026-09-30 ok
*.synclature.com 10 2026-05-15 2026-09-30 —
www.synclature.com 2 2026-08-02 2026-08-02 ok

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