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.

34 hosts · 387 ms

HostCertsFirst seenLast seenDNS
scalar.io 10 2025-11-13 2026-09-07 ok
*.scalar.io 6 2025-07-10 2026-07-25 —
data.scalar.io 1 2026-09-10 2026-09-10 nxdomain
index-data.scalar.io 2 2026-03-25 2026-08-25 ok
respond.scalar.io 1 2026-01-06 2026-01-06 ok
ws.respond.scalar.io 1 2026-01-09 2026-01-09 nxdomain
schedule.scalar.io 10 2026-05-09 2026-09-11 ok
emailstore.scalar.io 5 2026-05-13 2026-09-10 ok
credit-rating.scalar.io 4 2026-04-18 2026-08-16 ok
marketing.scalar.io 3 2026-04-27 2026-08-13 ok
api.scalar.io 3 2026-04-22 2026-09-22 ok
feedback.scalar.io 1 2026-06-04 2026-06-04 ok
api.feedback.scalar.io 1 2026-06-05 2026-06-05 ok
opsmanual.scalar.io 4 2026-05-31 2026-09-17 ok
mta-sts.email.scalar.io 3 2025-10-27 2026-09-27 nxdomain
hamm.scalar.io 9 2026-06-01 2026-09-28 ok
bitwarden.scalar.io 3 2025-10-20 2026-09-15 ok
dev.pantheon.scalar.io 4 2026-05-20 2026-07-21 ok
mcp.scalar.io 1 2026-10-01 2026-10-01 ok
app.scalar.io 1 2025-11-10 2025-11-10 ok
newsletter.scalar.io 5 2026-05-13 2026-09-13 ok
investor.scalar.io 1 2025-11-10 2025-11-10 ok
metrics.scalar.io 3 2026-05-12 2026-08-30 ok
docs.scalar.io 1 2026-02-11 2026-02-11 ok
limitless.scalar.io 2 2026-03-20 2026-08-20 ok
email-assets.scalar.io 2 2026-04-08 2026-09-08 ok
app.documents.scalar.io 1 2025-12-22 2025-12-22 ok
mta-sts.scalar.io 3 2025-10-27 2026-09-27 ok
status.scalar.io 5 2026-05-18 2026-09-15 ok
trust.scalar.io 14 2026-04-10 2026-10-05 ok
www.scalar.io 16 2026-04-07 2026-09-07 ok
software-index.scalar.io 1 2026-05-06 2026-05-06 ok
*.software-index.scalar.io 1 2026-05-06 2026-05-06 —
eml.mxmx.scalar.io 10 2026-04-24 2026-09-07 ok

Programmatic access, with DNS A records: API GET /v1/hosts/scalar.io (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/scalar.io.