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.

8 hosts · 328 ms

HostCertsFirst seenLast seenDNS
echoworx.com 12 2026-05-10 2026-09-25 ok
*.echoworx.com 12 2026-04-22 2026-09-25 —
mailbox.qa.echoworx.com 4 2026-04-22 2026-07-16 nodata
*.i.echoworx.com 4 2026-04-22 2026-07-16 —
aut-pineapple.i.echoworx.com 1 2026-08-24 2026-08-24 nodata
ldap.i.echoworx.com 2 2026-07-10 2026-07-10 nodata
nvd-mirror.i.echoworx.com 1 2026-08-24 2026-08-24 nodata
www.echoworx.com 4 2026-05-24 2026-09-25 ok

Programmatic access, with DNS A records: API GET /v1/hosts/echoworx.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/echoworx.com.