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.

5 hosts · 318 ms

HostCertsFirst seenLast seenDNS
flexibits.com 21 2026-04-13 2026-09-26 ok
*.flexibits.com 21 2026-04-13 2026-09-26 —
email.flexibits.com 5 2026-05-26 2026-09-22 ok
status.flexibits.com 7 2026-04-30 2026-09-10 ok
trust.flexibits.com 12 2026-06-06 2026-10-02 ok

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