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 · 336 ms

HostCertsFirst seenLast seenDNS
justbats.com 3 2026-06-04 2026-09-15 ok
dd.justbats.com 1 2026-08-26 2026-08-26 ok
mxhtd.justbats.com 7 2026-06-07 2026-10-03 ok
trade.justbats.com 7 2026-01-14 2026-10-02 ok
engage.justbats.com 12 2026-04-23 2026-08-19 ok
blog.justbats.com 2 2026-06-04 2026-06-17 ok
mailer.justbats.com 10 2026-04-23 2026-08-19 ok
www.justbats.com 2 2026-06-04 2026-06-17 ok

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