Check-Host.cc

Top-Level Domain

.io

Aggregated statistics for the top-level domain

Apex domains
we've enumerated
Subdomains seen
CT + DNS + brute
TLS certs
85,187
naming .io
Hosting ASNs
15
distinct origins

Domain Distribution

Apex domains with the most known subdomains — large orgs, telecoms, hosters.
Apex Subdomains
azurecontainerapps.io 3,499,284
keenetic.io 1,890,363
nip.io 349,848
sslip.io 287,274
azurecontainerapps-test.io 189,590
k4apps.io 176,590
nid.io 118,143
netcraze.io 117,554
starsweb.io 74,294
tktl.io 64,820
qzz.io 54,420
instruqt.io 31,342
nxcli.io 27,750
cloudhub.io 22,828
jsdelivr.io 19,471
aroapp-hcp.io 13,925
redhatworkshops.io 12,937
streamgpu.io 12,475
aroapp.io 11,890
cedevice.io 10,176
isccloud.io 9,150
tmachine.io 8,804
sfmc.io 8,298
wiz.io 8,003
upli.io 7,596
ikarem.io 7,515
icore.io 6,995
cxnpl.io 6,592
affiliatereel.io 6,127
azmk8s.io 5,982
galaxy-dev.io 5,609
cs-ide.io 5,441
fluffy-otter-5.telebit.io 4,950
cwan.io 4,898
sapcloud.io 4,877
lumar.io 4,792
backname.io 4,742
enablon.io 4,698
serious-cat-33.telebit.io 4,561
pegcloud.io 4,552
hotelengine.io 4,383
ordinary-elephant-58.telebit.io 4,379
zuddl.io 4,371
litegallery.io 4,324
wdr.io 4,268
gigantic.io 4,266
amazee.io 3,999
wet-crab-48.telebit.io 3,972
enotis.io 3,960
dishcloud.io 3,949

Top Certificate Issuers

Issuer (CA) Certs
Amazon 29,689
Let's Encrypt 24,449
ca 5,864
WR3 5,414
YR1 2,085
YR2 2,008
YE2 1,959
YE1 1,861
Sectigo 1,707
RunCloud WebSSL Root CA 1,602
DigiCert 1,386
Cloudflare 1,262
GoDaddy 729
ZeroSSL 449
GlobalSign 374

Top Hosting ASNs

ASN Name .io domains
AS16509 Amazon.com 363,408
AS8075 Microsoft 325,456
AS13335 Cloudflare 138,327
AS396982 Google Cloud 66,263
AS14061 DigitalOcean 58,153
AS24940 Hetzner Online 57,464
AS16276 OVHcloud 37,787
AS49505 Selectel Ltd. 29,536
AS214996 28,321
AS14618 Amazon AES 24,031
AS41722 Miran 23,458
AS47583 Hostinger International 17,309
AS206834 17,077
AS54113 Fastly, Inc. 14,915
AS34762 Combell 13,361

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 1,659
ℹ Coverage will improve significantly once CZDS zone-file access is granted for this TLD.