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 · 265 ms

HostCertsFirst seenLast seenDNS
zoner.de 1 2026-02-12 2026-02-12 ok
unternehmen.zoner.de 1 2025-10-08 2025-10-08 ok
lernen.zoner.de 3 2025-06-26 2026-07-01 ok
help.zoner.de 4 2026-04-20 2026-08-17 ok
www.zoner.de 1 2026-02-12 2026-02-12 ok

Programmatic access, with DNS A records: API GET /v1/hosts/zoner.de (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/zoner.de.