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.

6 hosts · 347 ms

HostCertsFirst seenLast seenDNS
nextload.com 17 2025-08-19 2026-10-06 ok
*.nextload.com 12 2025-09-30 2026-10-06 —
ftp.nextload.com 4 2026-07-04 2026-10-02 ok
autodiscover.nextload.com 7 2025-08-19 2026-08-25 ok
files.nextload.com 4 2026-07-04 2026-10-02 ok
mta-sts.nextload.com 5 2026-05-02 2026-08-28 ok

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