AS12519 FASTNETUK FastNet International Ltd

FASTNETUK FastNet International Ltd · registered in the United Kingdom

IPv4 addresses28,6724 prefixes · <0.001% of announced IPv4

Rank in United Kingdom#143largest network in GB by IPv4 space, of 2,074 · 0.04% of GB

Rank worldwide#5,116of 79,396 networks with IPv4

IPv61 x /32 (65,536 x /48)1 prefixes

CountryUnited Kingdom2,261 ASNs registered there

Open AS12519 in ASN lookup Look up an IP in this network (81.31.64.1) All networks in United Kingdom

IPv4 prefixes

All 4 prefixes, in address order.

81.31.64.0/20
82.148.32.0/19
87.252.32.0/19
212.42.160.0/19

IPv6 prefixes

All 1 prefix.

2a02:13a0::/32

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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