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 · 294 ms

HostCertsFirst seenLast seenDNS
e-file.com 4 2025-11-07 2026-09-30 ok
ga.e-file.com 6 2026-04-20 2026-09-30 ok
data.e-file.com 4 2026-04-08 2026-08-06 ok
secure.e-file.com 23 2025-10-17 2026-09-09 ok
*.secure.e-file.com 22 2026-04-15 2026-09-09 —
id.secure.e-file.com 4 2025-08-28 2026-08-29 ok
www.id.secure.e-file.com 4 2025-08-28 2026-08-29 nxdomain
www.secure.e-file.com 1 2025-10-17 2025-10-17 ok
feecollect.e-file.com 2 2026-03-10 2026-04-24 ok
www.feecollect.e-file.com 2 2026-03-10 2026-04-24 nxdomain
www.e-file.com 4 2025-11-07 2026-09-30 ok
bzuvlx.e-file.com 4 2026-05-07 2026-10-02 ok

Programmatic access, with DNS A records: API GET /v1/hosts/e-file.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/e-file.com.