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.

7 hosts · 262 ms

HostCertsFirst seenLast seen
dermamonitor.xyz 1 2026-03-13 2026-03-13
*.dermamonitor.xyz 1 2026-03-13 2026-03-13
*.mercury.us-east-1.dermamonitor.xyz 3 2025-09-28 2026-08-29
*.ap-northeast-1.dermamonitor.xyz 4 2025-06-12 2026-01-12
*.mercury.ap-northeast-1.dermamonitor.xyz 4 2025-06-12 2026-01-12
*.ap-southeast-1.dermamonitor.xyz 2 2025-11-01 2025-11-01
*.mercury.ap-southeast-1.dermamonitor.xyz 4 2025-09-28 2026-10-02

Programmatic access: API GET /v1/hosts/dermamonitor.xyz (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/dermamonitor.xyz.