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 · 289 ms

HostCertsFirst seenLast seenDNS
joebrowns.co.uk 6 2026-05-16 2026-09-13 ok
mcstaging2.joebrowns.co.uk 5 2026-05-29 2026-09-26 ok
data.joebrowns.co.uk 9 2026-05-09 2026-09-13 ok
mcprod.joebrowns.co.uk 6 2026-05-16 2026-09-13 ok
mcstaging.joebrowns.co.uk 5 2026-04-22 2026-08-20 ok
data.mcstaging.joebrowns.co.uk 8 2026-04-22 2026-08-23 ok
text.mcstaging.joebrowns.co.uk 8 2026-04-22 2026-09-07 ok
reporting.joebrowns.co.uk 2 2026-08-27 2026-09-13 ok
vpn.joebrowns.co.uk 2 2026-03-31 2026-09-29 ok
cybs.joebrowns.co.uk 1 2026-02-03 2026-02-03 ok
text.joebrowns.co.uk 10 2026-05-16 2026-09-20 ok
www.joebrowns.co.uk 6 2026-05-16 2026-09-13 ok

Programmatic access, with DNS A records: API GET /v1/hosts/joebrowns.co.uk (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/joebrowns.co.uk.