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.

20 hosts · 369 ms

HostCertsFirst seenLast seenDNS
koh.com 15 2026-05-17 2026-09-28 ok
wd.koh.com 10 2026-05-12 2026-09-08 ok
share.koh.com 14 2026-05-19 2026-09-29 ok
track.koh.com 4 2026-04-14 2026-08-12 ok
ktrk.koh.com 5 2026-07-17 2026-09-14 ok
inst-tk.koh.com 6 2026-06-26 2026-08-24 ok
uk.koh.com 14 2026-05-16 2026-09-26 ok
sms.uk.koh.com 6 2026-05-09 2026-09-04 ok
global.koh.com 2 2026-05-26 2026-07-25 ok
m.koh.com 3 2025-11-18 2026-07-31 ok
go.koh.com 4 2026-05-26 2026-09-23 ok
help.koh.com 12 2026-05-19 2026-09-14 ok
ukhelp.koh.com 10 2026-05-07 2026-09-02 ok
nzhelp.koh.com 16 2026-05-03 2026-08-29 ok
shop.koh.com 10 2026-05-15 2026-09-10 ok
sms.koh.com 6 2026-05-11 2026-09-06 ok
account.koh.com 13 2026-05-11 2026-09-23 ok
au.koh.com 15 2026-05-17 2026-09-27 ok
www.koh.com 15 2026-05-17 2026-09-27 ok
track-nz.koh.com 4 2026-04-14 2026-08-12 ok

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