AS13037 ZEN-AS Zen Internet Ltd

ZEN-AS Zen Internet Ltd · registered in the United Kingdom

IPv4 addresses527,61636 prefixes · 0.017% of announced IPv4

Rank in United Kingdom#15largest network in GB by IPv4 space, of 2,074 · 0.78% of GB

Rank worldwide#559of 79,396 networks with IPv4

IPv68 x /32 (524,288 x /48)1 prefixes

CountryUnited Kingdom2,261 ASNs registered there

Open AS13037 in ASN lookup Look up an IP in this network (51.148.0.1) All networks in United Kingdom

IPv4 prefixes

All 36 prefixes, in address order.

51.148.0.0/16
51.155.0.0/16
62.3.64.0/18
77.104.128.0/18
82.68.0.0/15
82.71.0.0/16
88.97.0.0/18
88.97.64.0/20
88.97.88.0/22
88.97.96.0/20
88.98.0.0/20
88.98.16.0/23
88.98.18.0/24
88.98.21.0/24
88.98.22.0/23
88.98.24.0/21
88.98.32.0/19
88.98.64.0/19
88.98.128.0/19
88.98.160.0/21
88.98.170.0/23
88.98.172.0/22
88.98.176.0/20
91.235.214.0/24
146.66.64.0/18
185.6.135.0/24
185.81.232.0/22
185.169.116.0/22
185.183.100.0/22
188.122.32.0/20
188.122.48.0/21
188.122.56.0/22
188.122.60.0/23
188.122.63.0/24
212.23.0.0/19
217.155.0.0/16

IPv6 prefixes

All 1 prefix.

2a02:8010::/29

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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