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 · 327 ms

HostCertsFirst seenLast seenDNS
balderton.events 15 2026-05-17 2026-09-16 nodata
*.balderton.events 9 2026-05-17 2026-09-13 —
invite.balderton.events 12 2026-04-21 2026-08-18 ok
mta-sts.balderton.events 6 2026-05-21 2026-09-16 ok

Programmatic access, with DNS A records: API GET /v1/hosts/balderton.events (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/balderton.events.