AS131913 JPNIC-4Byte-ASBLOCK-AP

AS131913-9 - JPNIC-4Byte-ASBLOCK-AP · registered in Japan

IPv4 addresses2561 prefixes · <0.001% of announced IPv4

Rank in Japan#706largest network in JP by IPv4 space, of 724 · <0.01% of JP

Rank worldwide#69,941of 79,396 networks with IPv4

IPv6noneno IPv6 routes announced

CountryJapan745 ASNs registered there

Open AS131913 in ASN lookup Look up an IP in this network (163.227.4.1) All networks in Japan

IPv4 prefixes

All 1 prefix, in address order.

163.227.4.0/24

Other ASNs named JPNIC-4Byte-ASBLOCK-AP

1 other network uses the same organisation name; together with AS131913 they announce 2,304 IPv4 addresses.

ASNNameIPv4 addresses

AS131971AS131971-67 - JPNIC-4Byte-ASBLOCK-AP JP2,048

Similar-sized networks in Japan

ASNNameIPv4 addresses

AS59124#703 KYOTO-PREF - KYOTO Prefectural Government256

AS131894#704 U-Cloud-2 - UNIADEX, LTD.256

AS131903#705 NRI-IVPN - Nomura Research Institute,Ltd.256

AS131989#707 PFU-UMC-MS01 - PFU LIMITED256

AS132211#708 FXCM-ASIA-AP - FX Corporate LLC256

AS133180#709 STARBOWLTD-AS-AP - Starbow Ltd.256

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