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.

16 hosts · 362 ms

HostCertsFirst seenLast seenDNS
securedata.com 27 2026-04-16 2026-10-04 ok
*.securedata.com 18 2026-05-12 2026-10-04 —
vpn500.securedata.com 2 2025-09-09 2026-09-17 ok
www.vpn500.securedata.com 2 2025-09-09 2026-09-17 nxdomain
rm.securedata.com 1 2026-06-04 2026-06-04 ok
www.rm.securedata.com 1 2026-06-04 2026-06-04 nxdomain
beta1partner.securedata.com 5 2026-04-29 2026-09-07 ok
beta2partner.securedata.com 5 2026-04-29 2026-09-07 ok
downloads.securedata.com 10 2026-04-19 2026-08-15 ok
services.securedata.com 2 2026-10-02 2026-10-02 ok
beta1securecms.securedata.com 5 2026-04-29 2026-09-07 ok
assets.securedata.com 8 2026-04-24 2026-08-21 ok
beta2account.securedata.com 5 2026-04-29 2026-09-07 ok
beta3account.securedata.com 5 2026-04-29 2026-09-17 ok
beta4account.securedata.com 5 2026-04-29 2026-09-07 ok
www.securedata.com 6 2026-04-14 2026-08-10 ok

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