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 · 278 ms

HostCertsFirst seenLast seenDNS
rhoen-rennsteig-sparkasse.de 4 2026-04-14 2026-09-30 ok
psd2-xs2a.rhoen-rennsteig-sparkasse.de 2 2025-08-26 2026-07-29 nxdomain
module.rhoen-rennsteig-sparkasse.de 4 2026-04-14 2026-09-30 ok
mailing.rhoen-rennsteig-sparkasse.de 5 2026-05-22 2026-09-19 ok
www.rhoen-rennsteig-sparkasse.de 4 2026-04-14 2026-09-30 ok

Programmatic access, with DNS A records: API GET /v1/hosts/rhoen-rennsteig-sparkasse.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/rhoen-rennsteig-sparkasse.de.