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.

12 hosts · 302 ms

HostCertsFirst seenLast seenDNS
dialux.com 3 2025-09-09 2026-08-10 ok
*.dialux.com 1 2026-04-20 2026-04-20 —
download.dialux.com 2 2025-09-09 2026-08-10 ok
live-xhqs4yxf.dialux.com 3 2026-03-23 2026-08-23 nodata
business-live-xhqs4yxf.dialux.com 3 2026-03-23 2026-08-23 nodata
test-xhqs4yxf.dialux.com 1 2026-01-18 2026-01-18 nodata
business-test-xhqs4yxf.dialux.com 1 2026-01-18 2026-01-18 nodata
business.dialux.com 3 2025-10-07 2026-09-07 ok
test.dialux.com 2 2025-08-10 2026-07-11 nodata
business-test.dialux.com 2 2025-08-11 2026-07-12 nodata
www.dialux.com 2 2025-09-09 2026-08-10 ok
community.dialux.com 10 2026-05-18 2026-09-13 ok

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