A list of all Japan ASNs including hosting providers, ISPs, and businesses with announced IPv4 and IPv6 prefixes.
| ASN | Type | IPv4 Routes | IPv6 Routes | Company |
|---|---|---|---|---|
| AS9605 | ISP & Mobile | 928 | 326 | NTT DOCOMO, INC. |
| AS2907 | Education | 667 | 2 | Research Organization of Information and Systems, National Institute of Informatics |
| AS2516 | ISP & Mobile | 563 | 9 | KDDI CORPORATION |
| AS2514 | ISP & Mobile | 468 | 4 | NTT PC Communications, Inc. |
| AS17676 | ISP & Mobile | 463 | 3 | SoftBank Corp. |
| AS10013 | Other Business | 407 | 3 | FreeBit Co.,Ltd. |
| AS4694 | Hosting Provider | 327 | 5 | IDC Frontier Inc. |
| AS9824 | ISP & Mobile | 231 | 62 | JCOM Co., Ltd. |
| AS7687 | Other Business | 211 | 0 | TOYOTA SYSTEMS CORPORATION |
| AS2497 | ISP & Mobile | 194 | 11 | Internet Initiative Japan Inc. |
| AS10010 | ISP & Mobile | 186 | 7 | TOKAI Communications Corporation |
| AS2519 | ISP & Mobile | 182 | 2 | ARTERIA Networks Corporation |
| AS58647 | Education | 182 | 0 | Kagawa University |
| AS4713 | ISP & Mobile | 180 | 6 | NTT COMMUNICATIONS CORPORATION |
| AS58791 | Other Business | 174 | 2 | GMO Internet, Inc. |
| AS4721 | ISP & Mobile | 162 | 1 | JCOM Co., Ltd. |
| AS38631 | Other Business | 147 | 116 | LY Corporation |
| AS4725 | ISP & Mobile | 144 | 1 | SoftBank Corp. |
| AS7524 | Other Business | 133 | 1 | ITEC HANKYU HANSHIN CO.,LTD. |
| AS55374 | Other Business | 129 | 4 | FUJITSU LIMITED |
| AS3258 | Other Business | 115 | 25 | xTom Japan Corporation |
| AS59109 | Other Business | 111 | 0 | Hitachi,Ltd., Managed Services Business Division |
| AS18283 | ISP & Mobile | 97 | 1 | Chupicom Inc. |
| AS9617 | ISP & Mobile | 85 | 33 | JCOM Co., Ltd. |
| AS2527 | ISP & Mobile | 74 | 2 | Sony Network Communications Inc. |
| AS151386 | Other Business | 73 | 0 | NHN Cloud Japan Corporation |
| AS131932 | Other Business | 71 | 0 | JR East Information Systems Company |
| AS17514 | Other Business | 67 | 1 | OTSUKA CORPORATION |
| AS17511 | ISP & Mobile | 66 | 1 | OPTAGE Inc. |
| AS4686 | ISP & Mobile | 65 | 1 | BEKKOAME INTERNET INC. |
| AS4685 | ISP & Mobile | 62 | 2 | Asahi Net |
| AS7671 | Hosting Provider | 61 | 2 | NTT SmartConnect Corporation |
| AS2510 | Other Business | 61 | 1 | FUJITSU LIMITED |
| AS18126 | ISP & Mobile | 60 | 2 | Chubu Telecommunications Company, Inc. |
| AS131965 | Hosting Provider | 59 | 2 | Xserver Inc. |
| AS10006 | Hosting Provider | 56 | 2 | SECOM Trust Systems Co.,Ltd. |
| AS18077 | ISP & Mobile | 54 | 1 | Yamaguchi Cable Vision Co., Ltd. |
| AS7522 | ISP & Mobile | 54 | 1 | STNet, Incorporated |
| AS18068 | ISP & Mobile | 51 | 2 | Dream Wave Shizuoka Co. Ltd. |
| AS7684 | Hosting Provider | 51 | 1 | SAKURA Internet Inc. |
| AS134351 | Hosting Provider | 50 | 2 | Leaseweb Japan K.K. |
| AS18092 | ISP & Mobile | 50 | 1 | Kyushu Tele Communications Company |
| AS132827 | Other Business | 48 | 0 | GATEWAY INC |
| AS7506 | Other Business | 47 | 6 | GMO Internet, Inc. |
| AS9622 | ISP & Mobile | 47 | 1 | Kurashiki Cable TV |
| AS59107 | ISP & Mobile | 47 | 0 | Hachinohe Cable Television Co. |
| AS131921 | Other Business | 46 | 13 | GMO GlobalSign Holdings K.K. |
| AS10021 | Other Business | 45 | 5 | KVH Co.,Ltd |
| AS9595 | Other Business | 45 | 4 | NTT-ME Corporation |
| AS59108 | ISP & Mobile | 45 | 1 | KATCH NETWORK INC. |
| AS17506 | ISP & Mobile | 40 | 1 | ARTERIA Networks Corporation |
| AS9370 | Hosting Provider | 39 | 5 | SAKURA Internet Inc. |
| AS18081 | Other Business | 38 | 1 | Kintetsu Cable Network Co., Ltd. |
| AS9354 | ISP & Mobile | 37 | 1 | Community Network Center Inc. |
| AS17698 | ISP & Mobile | 37 | 0 | COMMUNITY NETWORK CENTER INCORPORATED. |
| AS142622 | Other Business | 36 | 1 | Dream Information Laboratory |
| AS7679 | ISP & Mobile | 36 | 1 | QTnet,Inc. |
| AS9378 | ISP & Mobile | 36 | 0 | JCOM Co., Ltd. |
| AS55386 | Other Business | 35 | 3 | FUJITSU LIMITED |
| AS2518 | ISP & Mobile | 34 | 2 | BIGLOBE Inc. |
| AS24251 | ISP & Mobile | 33 | 0 | Iwakuni Cable Network Corporation |
| AS45691 | ISP & Mobile | 32 | 10 | DODO K.K. |
| AS138384 | ISP & Mobile | 31 | 1 | Rakuten Mobile, Inc. |
| AS9351 | ISP & Mobile | 30 | 1 | ZTV CO.,LTD |
| AS18526 | Hosting Provider | 29 | 5 | DDPS Networks, LLC |
| AS138968 | Other Business | 27 | 2 | rainbow network limited |
| AS18260 | ISP & Mobile | 27 | 1 | EHIME CATV CO.,LTD. |
| AS55900 | ISP & Mobile | 27 | 1 | GLBB Japan KK |
| AS23822 | ISP & Mobile | 27 | 0 | Hagi Cable Network Co.,Ltd |
| AS4673 | Other Business | 26 | 3 | NTT DATA CORPORATION |
| AS4680 | Other Business | 26 | 1 | Mitsubishi Electric Information Network Corporation |
| AS9597 | Hosting Provider | 26 | 1 | KDDI Web Communications Inc. |
| AS38638 | Other Business | 26 | 0 | Ip Core Corporation |
| AS17661 | Other Business | 25 | 0 | NHN Cloud Japan Corporation |
| AS9614 | ISP & Mobile | 25 | 0 | Oita Cable Telecom Co,ltd. |
| AS18134 | ISP & Mobile | 24 | 0 | JCOM Co., Ltd. |
| AS17707 | Hosting Provider | 23 | 4 | NHN Techorus Corp. |
| AS7676 | ISP & Mobile | 23 | 3 | TAM Co., Ltd. |
| AS17534 | Other Business | 23 | 2 | NSK Co.,Ltd. |
| AS9466 | ISP & Mobile | 23 | 2 | Verizon Japan Limited |
| AS131893 | Other Business | 22 | 3 | RICOH Company, Ltd. |
| AS17516 | Hosting Provider | 22 | 2 | NTT COMWARE CORPORATION |
| AS18144 | ISP & Mobile | 22 | 1 | Enecom,Inc. |
| AS37918 | ISP & Mobile | 22 | 1 | Nippon Telegraph and Telephone Corporation |
| AS7514 | Other Business | 22 | 1 | Computer Engineering & Consulting, Ltd. |
| AS9371 | Hosting Provider | 22 | 1 | SAKURA Internet Inc. |
| AS9374 | Other Business | 22 | 1 | EDION Corporation |
| AS23777 | Other Business | 21 | 2 | NTT BUSINESS SOLUTIONS CORPORATION |
| AS18075 | ISP & Mobile | 21 | 0 | Chupicom Inc. |
| AS23788 | ISP & Mobile | 21 | 0 | JCOM Co., Ltd. |
| AS10000 | ISP & Mobile | 20 | 1 | Nagasaki Cable Media Inc. |
| AS4711 | Other Business | 20 | 1 | INTEC Inc. |
| AS7672 | Other Business | 20 | 1 | Hokuden Information System Service Co.,Ltd. |
| AS17505 | ISP & Mobile | 20 | 0 | SoftBank Corp. |
| AS9607 | Hosting Provider | 19 | 3 | BroadBand Tower, Inc. |
| AS23783 | Other Business | 19 | 2 | Cable Networks Akita Co.,Ltd. |
| AS18097 | Other Business | 19 | 1 | D.C.N. Corporation |
| AS63793 | Hosting Provider | 19 | 1 | Japan OPS Better Co., Ltd. |
| AS7511 | ISP & Mobile | 19 | 1 | SYNAPSE Co.,Ltd. |
| AS7670 | ISP & Mobile | 19 | 1 | Energia Communications,Inc. |