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.

24 hosts · 254 ms

HostCertsFirst seenLast seenDNS
utila.io 30 2026-05-03 2026-08-31 ok
*.utila.io 3 2026-05-16 2026-08-31 —
*.dev-2.utila.io 3 2026-05-08 2026-08-25 —
*.prod.utila.io 3 2026-05-09 2026-08-26 —
intake.utila.io 20 2026-05-01 2026-08-27 ok
route.utila.io 5 2026-05-14 2026-09-11 ok
*.staging.utila.io 4 2026-04-11 2026-09-22 —
track.utila.io 7 2026-04-22 2026-08-30 ok
click.mail.utila.io 1 2026-08-24 2026-08-24 ok
login.utila.io 10 2026-04-30 2026-08-28 ok
*.dr.utila.io 1 2026-05-18 2026-05-18 —
newsletter.utila.io 16 2026-05-20 2026-09-15 ok
elink52b.newsletter.utila.io 6 2026-06-10 2026-08-08 ok
docs.utila.io 6 2026-04-27 2026-08-23 ok
*.docs.utila.io 3 2026-05-10 2026-08-29 —
resources.utila.io 10 2026-05-20 2026-09-15 ok
quotes.utila.io 14 2026-05-20 2026-09-15 ok
status.utila.io 5 2026-04-09 2026-10-04 ok
t.utila.io 8 2026-04-22 2026-08-18 ok
meet.utila.io 14 2026-04-16 2026-08-12 ok
support.utila.io 10 2026-04-30 2026-08-26 ok
trust.utila.io 10 2026-05-06 2026-09-02 ok
*.dev.utila.io 7 2026-04-09 2026-09-22 —
www.utila.io 13 2026-05-03 2026-08-30 ok

Programmatic access, with DNS A records: API GET /v1/hosts/utila.io (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/utila.io.