AS4721 JCOM Co., Ltd.

JCN - JCOM Co., Ltd. · registered in Japan

IPv4 addresses631,80854 prefixes · 0.020% of announced IPv4

Rank in Japan#24largest network in JP by IPv4 space, of 724 · 0.39% of JP

Rank worldwide#489of 79,396 networks with IPv4

IPv61 x /32 (65,536 x /48)1 prefixes

CountryJapan745 ASNs registered there

Open AS4721 in ASN lookup Look up an IP in this network (14.193.0.1) All networks in Japan

IPv4 prefixes

All 54 prefixes, in address order.

14.193.0.0/16
61.203.224.0/19
110.4.48.0/20
110.92.80.0/20
110.93.0.0/21
110.173.240.0/20
110.232.0.0/19
110.232.128.0/21
111.90.0.0/17
112.137.32.0/20
112.137.64.0/18
113.52.16.0/20
113.61.112.0/20
114.134.112.0/20
114.134.192.0/18
114.142.128.0/21
114.198.192.0/19
114.198.224.0/21
115.42.96.0/20
116.70.128.0/18
118.83.0.0/16
118.86.0.0/15
122.255.128.0/17
123.98.224.0/19
175.41.64.0/18
175.103.12.0/22
180.92.32.0/19
180.149.160.0/19
182.50.192.0/19
182.50.224.0/20
202.43.16.0/20
202.43.68.0/22
202.72.64.0/20
202.78.176.0/20
202.83.184.0/21
202.178.80.0/20
203.89.32.0/19
203.114.248.0/22
203.124.64.0/19
203.153.56.0/22
210.135.192.0/19
210.172.240.0/20
211.19.208.0/20
218.219.80.0/20
219.112.192.0/19
219.113.96.0/20
219.117.0.0/20
219.117.160.0/19
219.124.224.0/19
220.208.64.0/18
221.132.128.0/18
223.165.20.0/22
223.165.32.0/19
223.223.208.0/21

IPv6 prefixes

All 1 prefix.

2001:c30::/32

Other ASNs named JCOM Co., Ltd.

10 other networks use the same organisation name; together with AS4721 they announce 6,733,824 IPv4 addresses.

ASNNameIPv4 addresses

AS9824JTCL-JP-AS - JCOM Co., Ltd. JP4,745,216

AS9617ZAQ - JCOM Co., Ltd. JP1,163,264

AS9378CABLENET - JCOM Co., Ltd. JP45,056

AS18136CTA - JCOM Co., Ltd. JP43,008

AS18134KITANET - JCOM Co., Ltd. JP29,696

AS23788HICT - JCOM Co., Ltd. JP24,576

AS24276ICNET - JCOM Co., Ltd. JP20,480

AS23790KCN-TV - JCOM Co., Ltd. JP18,432

AS7686ATNETHOME - JCOM Co., Ltd. JP8,192

AS45675KMN-TOKYO - JCOM Co., Ltd. JP4,096

Similar-sized networks in Japan

ASNNameIPv4 addresses

AS9617#21 ZAQ - JCOM Co., Ltd.1,163,264

AS4694#22 IDCF - IDC Frontier Inc.1,040,896

AS7679#23 QTNET - QTnet,Inc.760,832

AS7522#25 STCN - STNet, Incorporated594,944

AS7671#26 MCNET - NTT SmartConnect Corporation453,888

AS18081#27 KCN - Kintetsu Cable Network Co., Ltd.442,368

IP-to-ASN data: iptoasn.com (public domain). Snapshot downloaded 2026-11-11, refreshed daily. Ranges are what each network announces in BGP, not registry allocations. Data sources