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 · 449 ms

HostCertsFirst seenLast seenDNS
weareharris.com 3 2025-11-01 2026-09-28 ok
*.weareharris.com 3 2025-11-01 2026-09-28 —
time.weareharris.com 3 2025-09-05 2026-07-17 ok
expense.weareharris.com 3 2025-09-05 2026-07-17 ok
itglue.weareharris.com 2 2026-04-09 2026-09-09 ok
harrislink.weareharris.com 2 2026-03-08 2026-07-19 ok
email.weareharris.com 8 2026-05-21 2026-09-16 ok
vpn.weareharris.com 5 2025-07-17 2026-07-23 ok
www.vpn.weareharris.com 5 2025-07-17 2026-07-23 nxdomain
erp.weareharris.com 3 2025-09-05 2026-07-17 ok
links.weareharris.com 9 2026-05-21 2026-09-16 ok
support.weareharris.com 3 2025-09-05 2026-07-17 ok

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