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.

4 hosts · 257 ms

HostCertsFirst seenLast seenDNS
questeducation.fr 2 2025-07-23 2026-06-23 ok
*.questeducation.fr 2 2025-07-23 2026-06-23 —
wordpress.questeducation.fr 4 2026-04-07 2026-08-05 ok
www.questeducation.fr 5 2026-05-16 2026-09-13 ok

Programmatic access, with DNS A records: API GET /v1/hosts/questeducation.fr (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/questeducation.fr.