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 · 242 ms

HostCertsFirst seenLast seenDNS
cloud.emails.zappos.com 3 2026-03-17 2026-08-19 ok
image.emails.zappos.com 2 2025-12-08 2026-04-30 ok
click.emails.zappos.com 4 2026-03-17 2026-08-24 ok
view.emails.zappos.com 4 2026-03-17 2026-08-19 ok

Programmatic access, with DNS A records: API GET /v1/hosts/emails.zappos.com (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/emails.zappos.com.