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.

11 hosts · 264 ms

HostCertsFirst seenLast seenDNS
ajcomputers.com 5 2026-05-14 2026-09-11 ok
sitehealth.ajcomputers.com 1 2026-09-27 2026-09-27 ok
timetrack.ajcomputers.com 2 2026-07-12 2026-09-10 ok
*.mcp.ajcomputers.com 4 2026-04-14 2026-08-11 —
myip.ajcomputers.com 5 2026-06-04 2026-10-02 ok
tidbyt.apis.ajcomputers.com 5 2026-05-07 2026-09-04 ok
tools.ajcomputers.com 1 2026-09-27 2026-09-27 ok
plugins.ajcomputers.com 1 2026-08-21 2026-08-21 ok
www.ajcomputers.com 5 2026-05-14 2026-09-11 ok
3cxpbx.ajcomputers.com 1 2026-05-04 2026-05-04 ok
www.3cxpbx.ajcomputers.com 1 2026-05-04 2026-05-04 nxdomain

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