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.

6 hosts · 284 ms

HostCertsFirst seenLast seenDNS
psw.de 1 2025-07-14 2025-07-14 ok
*.psw.de 1 2025-07-14 2025-07-14 —
mx01.psw.de 1 2026-01-27 2026-01-27 nxdomain
rpmailing.psw.de 3 2026-05-22 2026-08-06 ok
mail.psw.de 1 2025-11-03 2025-11-03 ok
autodiscover.psw.de 1 2025-11-03 2025-11-03 ok

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