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.

54 hosts · 669 ms

HostCertsFirst seenLast seenDNS
close.com 72 2026-03-16 2026-09-29 ok
*.close.com 12 2026-03-16 2026-09-20 —
api.adc.close.com 2 2026-08-24 2026-08-24 ok
evs.adc.close.com 2 2026-08-24 2026-08-24 ok
nylas-a-googlewebhooksync.close.com 5 2026-05-22 2026-09-19 ok
nylas-b-googlewebhooksync.close.com 5 2026-05-22 2026-09-19 ok
nylas-c-googlewebhooksync.close.com 6 2026-05-22 2026-09-18 ok
nylas-d-googlewebhooksync.close.com 5 2026-05-22 2026-09-19 ok
nylas-e-googlewebhooksync.close.com 5 2026-05-21 2026-09-18 ok
nylas-f-googlewebhooksync.close.com 5 2026-05-21 2026-09-18 ok
nylas-g-googlewebhooksync.close.com 5 2026-06-01 2026-09-29 ok
events-service.close.com 4 2026-06-04 2026-10-02 ok
wf.close.com 7 2026-05-26 2026-09-21 ok
staging.close.com 5 2026-05-27 2026-09-24 ok
making.close.com 5 2026-04-26 2026-08-29 ok
api.close.com 5 2026-05-27 2026-09-24 ok
staging-api.close.com 5 2026-05-27 2026-09-24 ok
local-api.close.com 1 2026-03-12 2026-03-12 nxdomain
tunnel-api.close.com 1 2026-03-12 2026-03-12 nxdomain
importer-api.close.com 4 2026-04-16 2026-08-14 ok
storybook.close.com 5 2026-05-27 2026-09-24 ok
local.close.com 1 2026-03-12 2026-03-12 nxdomain
local-internal.close.com 1 2026-03-12 2026-03-12 nxdomain
app-internal.close.com 5 2026-05-27 2026-09-24 ok
dialer-internal.close.com 5 2026-04-23 2026-08-21 ok
tunnel.close.com 1 2026-03-12 2026-03-12 ok
ws-gql.close.com 5 2026-04-23 2026-08-21 ok
design.close.com 3 2026-06-02 2026-08-03 ok
admin.close.com 5 2026-05-22 2026-09-19 ok
demo.close.com 5 2026-04-24 2026-08-27 ok
mcp.close.com 5 2026-05-18 2026-09-15 ok
help.close.com 13 2026-04-25 2026-09-22 ok
app.close.com 5 2026-05-27 2026-09-24 ok
refer.close.com 10 2026-05-05 2026-08-31 ok
dialer.close.com 5 2026-05-22 2026-09-19 ok
developer.close.com 5 2026-04-29 2026-08-31 ok
importer.close.com 4 2026-04-16 2026-08-14 ok
authalligator.close.com 4 2026-04-16 2026-08-14 ok
resource-downloads.close.com 6 2026-05-02 2026-09-08 ok
services.close.com 5 2026-04-27 2026-08-25 ok
support-tools.close.com 5 2026-05-15 2026-09-15 ok
webforms.close.com 4 2026-04-15 2026-08-13 ok
staging-webforms.close.com 4 2026-04-13 2026-08-11 ok
srcmaps.close.com 5 2026-06-02 2026-09-30 ok
staging-srcmaps.close.com 4 2026-04-14 2026-08-12 ok
apps.close.com 2 2026-09-21 2026-09-21 nodata
*.apps.close.com 2 2026-09-21 2026-09-21 —
partners.close.com 5 2026-04-09 2026-08-06 ok
status.close.com 5 2026-05-01 2026-08-28 ok
ws.close.com 4 2026-04-11 2026-08-09 ok
previews.close.com 5 2026-04-23 2026-08-26 nxdomain
*.previews.close.com 10 2026-04-23 2026-09-01 —
trust.close.com 8 2026-05-04 2026-08-30 ok
www.close.com 17 2026-05-15 2026-09-21 ok

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