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.

10 hosts · 266 ms

HostCertsFirst seenLast seenDNS
thekallang.com.sg 20 2025-10-24 2026-09-16 ok
*.thekallang.com.sg 18 2025-10-24 2026-09-16 —
maintenance.thekallang.com.sg 2 2026-06-24 2026-06-24 nxdomain
*.maintenance.thekallang.com.sg 2 2026-06-24 2026-06-24 —
fwtrack.thekallang.com.sg 4 2026-06-01 2026-10-06 ok
cloud.mail.thekallang.com.sg 1 2025-12-10 2025-12-10 ok
image.mail.thekallang.com.sg 30 2025-12-10 2026-01-27 ok
click.mail.thekallang.com.sg 1 2025-12-10 2025-12-10 ok
view.mail.thekallang.com.sg 1 2025-12-10 2025-12-10 ok
insights.thekallang.com.sg 4 2026-04-20 2026-09-07 ok

Programmatic access, with DNS A records: API GET /v1/hosts/thekallang.com.sg (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/thekallang.com.sg.