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 · 261 ms

HostCertsFirst seenLast seenDNS
kfw.co.uk 14 2025-09-29 2026-09-18 ok
*.kfw.co.uk 13 2025-09-29 2026-09-18 —
mta-sts.kfw.co.uk 3 2026-06-10 2026-08-20 ok
www.kfw.co.uk 1 2025-10-06 2025-10-06 ok

Programmatic access, with DNS A records: API GET /v1/hosts/kfw.co.uk (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/kfw.co.uk.