AS15404 COLT Technology Services Group Limited

COLT Technology Services Group Limited · registered in the United Kingdom

IPv4 addresses142,336127 prefixes · 0.005% of announced IPv4

Rank in United Kingdom#33largest network in GB by IPv4 space, of 2,074 · 0.21% of GB

Rank worldwide#1,389of 79,396 networks with IPv4

IPv61 x /32 (69,639 x /48)9 prefixes

CountryUnited Kingdom2,261 ASNs registered there

Open AS15404 in ASN lookup Look up an IP in this network (5.11.96.1) All networks in United Kingdom

IPv4 prefixes

All 127 prefixes, in address order.

5.11.96.0/20
45.129.69.0/24
46.28.212.0/24
51.64.34.0/23
62.67.207.0/24
62.85.160.0/19
62.182.250.0/24
77.74.158.0/23
85.208.193.0/24
91.209.87.0/24
91.212.245.0/24
91.213.65.0/24
91.213.68.0/24
91.213.91.0/24
91.213.110.0/24
91.238.4.0/24
91.244.125.0/24
109.107.145.0/24
129.35.17.0/24
129.35.20.0/23
129.35.85.0/24
139.138.235.0/24
141.98.45.0/24
148.188.0.0/20
148.188.192.0/20
148.188.224.0/22
148.188.232.0/21
155.137.0.0/22
155.137.7.0/24
156.118.0.0/24
156.118.6.0/24
156.118.8.0/24
157.239.128.0/23
158.156.155.0/24
158.156.162.0/24
158.156.172.0/24
158.156.182.0/24
158.156.193.0/24
161.17.0.0/16
163.199.254.0/24
170.200.251.0/24
170.200.252.0/23
170.248.142.0/24
170.251.108.0/24
170.252.84.0/23
170.252.86.0/24
176.119.201.0/24
178.249.200.0/21
185.13.62.0/24
185.60.76.0/23
185.60.79.0/24
185.134.140.0/24
185.140.104.0/24
185.154.148.0/23
185.199.204.0/24
185.203.232.0/24
185.212.156.0/22
185.213.216.0/23
185.218.120.0/22
185.226.224.0/24
185.234.136.0/24
188.64.17.0/24
188.64.18.0/23
192.31.22.0/24
192.76.161.0/24
192.109.222.0/24
192.166.107.0/24
192.228.1.0/24
192.228.2.0/23
192.231.17.0/24
192.232.64.0/24
192.232.66.0/24
193.8.64.0/22
193.26.246.0/23
193.26.248.0/21
193.28.71.0/24
193.29.146.0/23
193.29.150.0/23
193.29.152.0/22
193.29.156.0/23
193.29.159.0/24
193.38.200.0/24
193.46.62.0/24
193.47.140.0/24
193.53.174.0/24
193.53.185.0/24
193.53.186.0/24
193.53.188.0/24
193.53.190.0/24
193.56.33.0/24
193.57.56.0/24
193.58.6.0/24
193.73.113.0/24
193.102.79.0/24
193.102.174.0/24
193.103.129.0/24
193.135.254.0/24
193.164.14.0/24
193.176.112.0/22
193.177.180.0/23
193.200.191.0/24
194.11.129.0/24
194.15.16.0/24
194.15.18.0/24
194.15.242.0/23
194.15.244.0/22
194.33.183.0/24
194.39.220.0/24
194.59.96.0/20
194.59.112.0/21
194.59.120.0/23
194.59.122.0/23
194.59.124.0/22
194.59.137.0/24
194.59.139.0/24
194.76.8.0/23
194.99.12.0/24
194.99.120.0/21
194.117.239.0/24
194.126.242.0/24
194.173.47.0/24
195.47.207.0/24
195.182.60.0/24
195.234.175.0/24
202.246.252.0/24
202.252.108.0/23
213.163.237.0/24

IPv6 prefixes

All 9 prefixes.

2001:678:274::/48
2001:67c:67c::/48
2001:67c:2b20::/48
2001:67c:2ea0::/48
2a02:11f8:70::/48
2a07:cb81::/32
2a0a:d6c0:145::/48
2a10:8802::/36
2a11:4d40::/48

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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