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.

5 hosts · 321 ms

HostCertsFirst seenLast seenDNS
ezo.io 3 2025-09-02 2026-07-30 ok
*.ezo.io 3 2025-09-02 2026-07-30 —
mta-sts.ezo.io 3 2026-05-27 2026-08-06 ok
get.ezo.io 15 2026-05-11 2026-09-17 ok
start.ezo.io 8 2026-04-26 2026-08-22 ok

Programmatic access, with DNS A records: API GET /v1/hosts/ezo.io (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/ezo.io.