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 · 306 ms

HostCertsFirst seenLast seenDNS
altova.com 6 2025-10-14 2026-08-19 ok
*.altova.com 2 2025-10-21 2026-01-29 —
h3.altova.com 2 2025-06-14 2026-05-15 ok
*.vie.altova.com 1 2026-01-29 2026-01-29 —
blog.altova.com 4 2025-10-14 2026-08-19 ok
*.ai.altova.com 1 2026-01-29 2026-01-29 —
*.bos.altova.com 1 2026-01-29 2026-01-29 —
us.altova.com 1 2026-04-10 2026-04-10 nodata
*.us.altova.com 2 2026-01-29 2026-04-10 —
*.eu.altova.com 1 2026-01-29 2026-01-29 —
cdn.sw.altova.com 1 2026-02-02 2026-02-02 ok
www.altova.com 4 2025-10-14 2026-08-19 ok

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