Find every subdomain
of a domain.

Every hostname under a domain that ever appeared in a public TLS certificate — with certificate counts and first/last seen dates.

4 hosts · 218 ms

HostCertsFirst seenLast seen
certic.info 10 2026-04-30 2026-09-10
projects.certic.info 5 2026-05-28 2026-09-25
mta-sts.certic.info 5 2026-05-13 2026-09-10
www.certic.info 10 2026-04-30 2026-09-10

Programmatic access: API GET /v1/hosts/certic.info (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/certic.info.