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 · 324 ms

HostCertsFirst seenLast seenDNS
cloud.e.npr.org 1 2026-01-11 2026-01-11 servfail
image.e.npr.org 3 2025-12-04 2026-08-31 ok
click.e.npr.org 2 2026-01-11 2026-01-12 ok
view.e.npr.org 1 2026-01-11 2026-01-11 ok

Programmatic access, with DNS A records: API GET /v1/hosts/e.npr.org (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/e.npr.org.