Check-Host.cc

Top-Level Domain

.io

Aggregated statistics for the top-level domain

Apex domains
we've enumerated
Subdomains seen
10,392,036
CT + DNS + brute
TLS certs
88,038
naming .io
Hosting ASNs
distinct origins

Domain Distribution

Apex domains with the most known subdomains — large orgs, telecoms, hosters.
Apex Subdomains
azurecontainerapps.io 3,576,220
keenetic.io 1,980,019
nip.io 375,079
netcraze.io 356,510
sslip.io 324,643
azurecontainerapps-test.io 194,021
k4apps.io 179,804
nid.io 118,145
starsweb.io 74,550
tktl.io 65,070
qzz.io 58,172
instruqt.io 32,768
nxcli.io 29,265
cloudhub.io 23,490
jsdelivr.io 19,471
isccloud.io 17,394
aroapp-hcp.io 14,271
streamgpu.io 14,178
redhatworkshops.io 13,304
aroapp.io 12,202
cedevice.io 10,218
tmachine.io 9,335
sfmc.io 8,481
wiz.io 8,053
ikarem.io 7,672
upli.io 7,648
azmk8s.io 7,243
icore.io 6,998
cxnpl.io 6,621
affiliatereel.io 6,169
galaxy-dev.io 5,968
cs-ide.io 5,600
fluffy-otter-5.telebit.io 5,159
sapcloud.io 5,108
cwan.io 4,915
serious-cat-33.telebit.io 4,871
backname.io 4,802
lumar.io 4,802
pegcloud.io 4,727
enablon.io 4,718
ordinary-elephant-58.telebit.io 4,700
zuddl.io 4,693
wdr.io 4,451
hotelengine.io 4,383
litegallery.io 4,368
gigantic.io 4,305
amazee.io 4,297
sehlat.io 4,103
wet-crab-48.telebit.io 4,088
enotis.io 4,074

Top Certificate Issuers

Issuer (CA) Certs
Amazon 29,722
Let's Encrypt 24,616
ca 7,120
WR3 5,682
YR1 2,269
YR2 2,196
YE2 2,177
YE1 2,053
Sectigo 1,749
RunCloud WebSSL Root CA 1,649
DigiCert 1,413
Cloudflare 1,302
GoDaddy 744
ZeroSSL 464
GlobalSign 385

Top Hosting ASNs

No hosting attribution yet

Forward-DNS crawler hasn't resolved enough .io apexes to BGP-attributable IPs.

Tech-Stack Distribution

No Wappalyzer detections

Body-fetcher hasn't covered enough .io sites yet for stack patterns to emerge.

Threat-intel hits

Feed Category Domains
openphish phishing 1,746
ℹ Coverage will improve significantly once CZDS zone-file access is granted for this TLD.