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.

9 hosts · 335 ms

HostCertsFirst seenLast seenDNS
onlineprinters.com 1 2026-02-24 2026-02-24 ok
*.onlineprinters.com 1 2026-02-24 2026-02-24 —
bounce.onlineprinters.com 1 2026-09-14 2026-09-14 ok
design.onlineprinters.com 5 2026-04-27 2026-08-21 servfail
smtp2go.onlineprinters.com 5 2026-05-18 2026-09-15 servfail
bounce.shop.onlineprinters.com 1 2026-09-14 2026-09-14 ok
investorrelations.onlineprinters.com 5 2026-05-02 2026-08-30 ok
insights.onlineprinters.com 3 2026-05-20 2026-09-06 ok
punchout.onlineprinters.com 1 2026-02-18 2026-02-18 ok

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