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 · 254 ms

HostCertsFirst seenLast seenDNS
cloud.sfmc.edx.org 2 2025-06-07 2026-05-25 ok
image.sfmc.edx.org 3 2026-04-06 2026-09-06 ok
click.sfmc.edx.org 3 2025-11-14 2025-11-14 ok
view.sfmc.edx.org 3 2025-11-14 2025-11-14 ok

Programmatic access, with DNS A records: API GET /v1/hosts/sfmc.edx.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/sfmc.edx.org.