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.

45 hosts · 343 ms

HostCertsFirst seenLast seenDNS
blu.com 4 2025-07-31 2026-06-04 ok
*.blu.com 4 2025-07-31 2026-06-04 —
www.registracia.blu.com 5 2026-06-18 2026-09-15 ok
support-be.blu.com 6 2026-05-03 2026-09-01 ok
support-de.blu.com 6 2026-05-03 2026-09-01 ok
link.de.blu.com 9 2026-05-05 2026-09-15 ok
support-ie.blu.com 6 2026-05-03 2026-09-01 ok
honboarding.blu.com 9 2026-05-05 2026-09-15 ok
www.honboarding.blu.com 9 2026-05-05 2026-09-15 ok
api.staging.blu.com 4 2026-05-26 2026-09-15 ok
login.staging.blu.com 12 2026-05-05 2026-09-25 ok
support-uk.blu.com 6 2026-05-03 2026-09-01 ok
link.uk.blu.com 9 2026-05-05 2026-09-15 ok
support-nl.blu.com 6 2026-05-03 2026-09-01 ok
login.blu.com 2 2026-01-12 2026-05-31 ok
activation.blu.com 5 2026-05-17 2026-09-14 ok
support-jp.blu.com 6 2026-05-03 2026-09-01 ok
partner.blu.com 7 2026-04-13 2026-10-06 ok
support-fr.blu.com 6 2026-05-03 2026-09-01 ok
link.fr.blu.com 9 2026-05-05 2026-09-15 ok
support-gr.blu.com 6 2026-05-03 2026-09-01 ok
link.gr.blu.com 9 2026-05-05 2026-09-15 ok
qr.blu.com 2 2026-02-24 2026-06-16 ok
support-es.blu.com 6 2026-05-03 2026-09-01 ok
link.es.blu.com 9 2026-05-05 2026-09-15 ok
clicks.blu.com 1 2026-09-14 2026-09-14 ok
stms.blu.com 3 2026-05-26 2026-09-11 ok
us.blu.com 2 2026-03-09 2026-07-20 ok
support-us.blu.com 6 2026-05-03 2026-09-01 ok
qa.us.blu.com 2 2026-03-26 2026-08-04 ok
www.qa.us.blu.com 2 2026-03-26 2026-08-04 ok
api.us.blu.com 2 2026-02-18 2026-06-10 ok
clicks.email.us.blu.com 2 2026-05-21 2026-10-02 ok
www.us.blu.com 2 2026-03-09 2026-07-20 ok
clicks.trx.us.blu.com 3 2026-05-21 2026-10-02 ok
support-it.blu.com 6 2026-05-03 2026-09-01 ok
link.it.blu.com 9 2026-05-05 2026-09-15 ok
link.pt.blu.com 9 2026-05-05 2026-09-15 ok
api.test.blu.com 4 2026-05-26 2026-09-15 ok
login.test.blu.com 11 2026-05-05 2026-09-25 ok
optlist.blu.com 1 2026-06-17 2026-06-17 ok
support-ru.blu.com 6 2026-05-03 2026-09-01 ok
support-cz.blu.com 6 2026-05-03 2026-09-01 ok
link.cz.blu.com 9 2026-05-05 2026-09-15 ok
link.nz.blu.com 9 2026-05-05 2026-09-15 ok

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