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 · 309 ms

HostCertsFirst seenLast seenDNS
tracking.cds-mail.dmm.inc 1 2026-07-07 2026-07-07 ok
stg.tracking.cds-mail.dmm.inc 1 2026-07-07 2026-07-07 ok
dev.tracking.cds-mail.dmm.inc 1 2026-07-02 2026-07-02 ok
r.dmm.inc 1 2025-10-16 2025-10-16 ok

Programmatic access, with DNS A records: API GET /v1/hosts/dmm.inc (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/dmm.inc.