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.

6 hosts · 320 ms

HostCertsFirst seenLast seenDNS
royalsundaram.in 3 2025-09-10 2026-07-21 ok
*.royalsundaram.in 3 2025-09-10 2026-07-21 —
tracking.ib42699.royalsundaram.in 1 2026-09-10 2026-09-10 ok
supporthub.royalsundaram.in 38 2026-04-26 2026-08-25 ok
infosec.royalsundaram.in 129 2026-04-09 2026-06-28 nxdomain
journaling.royalsundaram.in 1 2026-01-28 2026-01-28 ok

Programmatic access, with DNS A records: API GET /v1/hosts/royalsundaram.in (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/royalsundaram.in.