Find every subdomain
of a domain.

Every hostname under a domain that ever appeared in a public TLS certificate — with certificate counts and first/last seen dates.

3 hosts · 256 ms

HostCertsFirst seenLast seen
www.j2rsolutions.us 1 2025-08-09 2025-08-09
pay.j2rsolutions.us 1 2026-05-30 2026-05-30
www.pay.j2rsolutions.us 1 2026-05-30 2026-05-30

Programmatic access: API GET /v1/hosts/j2rsolutions.us (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/j2rsolutions.us.