Networks in Japan

745 autonomous systems are registered in Japan (JP). Together they announce 161,326,399 IPv4 addresses, 5.15% of the announced total, which ranks Japan #3 of 240 countries.

Autonomous systems745724 announce IPv4, 21 IPv6 only

IPv4 addresses161,326,3995.15% of announced IPv4 · #3 worldwide

Top 5 networks hold61.5%of Japan's IPv4 space

IPv67,828 x /32 (513,066,755 x /48)432 of 745 networks (58%) announce IPv6

Small networks91announce a single /24 (256 addresses) or less

Look up AS17676, the largest network in JP Look up any IP or ASN

Top 50 networks in Japan by IPv4 space

#ASNNetworkIPv4 addressesOf JP

1 AS17676 GIGAINFRA - SoftBank Corp. 38,445,056 23.83%

2 AS4713 OCN - NTT DOCOMO BUSINESS,Inc. 28,623,360 17.74%

3 AS2516 KDDI - KDDI CORPORATION 18,072,320 11.20%

4 AS2907 SINET-AS - Research Organization of Information and Systems, National Institute of Informatics 8,765,504 5.43%

5 AS17506 UCOM - ARTERIA Networks Corporation 5,382,143 3.34%

6 AS9824 JTCL-JP-AS - JCOM Co., Ltd. 4,745,216 2.94%

7 AS2497 IIJ - Internet Initiative Japan Inc. 4,094,976 2.54%

8 AS2527 So-net - Sony Network Communications Inc. 3,867,648 2.40%

9 AS2518 BIGLOBE - BIGLOBE Inc. 3,670,016 2.27%

10 AS17511 OPTAGE - OPTAGE Inc. 2,994,432 1.86%

11 AS9605 docomo - NTT DOCOMO, INC. 2,536,448 1.57%

12 AS2514 InfoSphere - NTT PC Communications, Inc. 2,078,976 1.29%

13 AS10013 FBDC - FreeBit Co.,Ltd. 1,944,064 1.21%

14 AS4725 ODN - SoftBank Corp. 1,918,976 1.19%

15 AS9595 XEPHION - NTT-ME Corporation 1,513,472 0.94%

16 AS2510 INFOWEB - FUJITSU LIMITED 1,509,376 0.94%

17 AS18126 CTCX - Chubu Telecommunications Company, Inc. 1,505,536 0.93%

18 AS10010 TOKAI - TOKAI Communications Corporation 1,497,088 0.93%

19 AS2519 VECTANT - ARTERIA Networks Corporation 1,464,320 0.91%

20 AS4685 ASAHI-NET - Asahi Net 1,277,952 0.79%

21 AS9617 ZAQ - JCOM Co., Ltd. 1,163,264 0.72%

22 AS4694 IDCF - IDC Frontier Inc. 1,040,896 0.65%

23 AS7679 QTNET - QTnet,Inc. 760,832 0.47%

24 AS4721 JCN - JCOM Co., Ltd. 631,808 0.39%

25 AS7522 STCN - STNet, Incorporated 594,944 0.37%

26 AS7671 MCNET - NTT SmartConnect Corporation 453,888 0.28%

27 AS18081 KCN - Kintetsu Cable Network Co., Ltd. 442,368 0.27%

28 AS138384 RMNI-AS-AP - Rakuten Mobile Network, Inc. 420,864 0.26%

29 AS9365 iTSCOM - its communications Inc. 404,480 0.25%

30 AS18071 MEI1 - Panasonic Information Systems Co., Ltd 383,232 0.24%

31 AS7684 SAKURA-A - SAKURA Internet Inc. 368,640 0.23%

32 AS7524 HANSHIN - ITEC HANKYU HANSHIN CO.,LTD. 366,336 0.23%

33 AS9370 SAKURA-B - SAKURA Internet Inc. 340,992 0.21%

34 AS131932 JEIS-NET - JR East Information Systems Company 327,680 0.20%

35 AS9371 SAKURA-C - SAKURA Internet Inc. 297,216 0.18%

36 AS18144 AS-ENECOM - Enecom,Inc. 291,840 0.18%

37 AS9597 CPI-NET - KDDI Web Communications Inc. 276,736 0.17%

38 AS7506 GMO-I-R1 - GMO Internet, Inc. 252,672 0.16%

39 AS9351 ZLAN - ZTV CO.,LTD 249,856 0.15%

40 AS4673 INTERVIA - NTT DATA CORPORATION 241,664 0.15%

41 AS2522 PPP-EXP - Japan Network Information Center 229,120 0.14%

42 AS2506 SuperCSI - NTT business Solutions corporation 214,272 0.13%

43 AS7687 D-CRUISENET - TOYOTA SYSTEMS CORPORATION 200,960 0.12%

44 AS2501 UTnet - The University of Tokyo 200,704 0.12%

45 AS4686 BEKKOAME - BEKKOAME INTERNET INC. 200,448 0.12%

46 AS9354 TDNC - Community Network Center Inc. 200,448 0.12%

47 AS23793 AIST - National Institute of Advanced Industrial Science and Technology 199,936 0.12%

48 AS9619 SSD - Sony Global Solutions Inc. 199,680 0.12%

49 AS7514 MEX - Computer Engineering & Consulting, Ltd. 192,000 0.12%

50 AS17698 CCNET-NET - COMMUNITY NETWORK CENTER INCORPORATED. 174,080 0.11%

Countries of similar size

#1 United States #2 China #4 Germany #5 South Korea #6 Brazil All countries

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