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.

9 hosts · 346 ms

HostCertsFirst seenLast seenDNS
southwesttraders.com 9 2026-06-01 2026-09-27 ok
b2b2.southwesttraders.com 1 2026-02-11 2026-02-11 ok
portal2.southwesttraders.com 4 2026-06-06 2026-10-04 ok
blue.southwesttraders.com 4 2026-04-20 2026-08-18 ok
portal.southwesttraders.com 5 2026-05-19 2026-10-04 ok
www.portal.southwesttraders.com 1 2026-05-19 2026-05-19 nxdomain
mta-sts.smtp.southwesttraders.com 1 2026-06-15 2026-06-15 ok
mta-sts.southwesttraders.com 1 2026-06-15 2026-06-15 ok
www.southwesttraders.com 10 2026-06-01 2026-09-28 ok

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