I have been struggling to find a published list of prefixes for public internet address spaces, therefore I have compiled my own using the documentation available from IANA (http://www.iana.org/assignments/ipv4-address-space/ipv4-address-space.xhtml). The prefixes below are a simplified version which doesn’t exclude the documentation use ranges as this added many extras that just weren’t needed for my purposes.

Public Prefixes

These are prefixes to all IP Addresses which are accessible across the public internet.

1.0.0.0/8 2.0.0.0/7 4.0.0.0/6 8.0.0.0/7 11.0.0.0/8 12.0.0.0/6 16.0.0.0/4 32.0.0.0/3 64.0.0.0/3 96.0.0.0/4 112.0.0.0/5 120.0.0.0/6 124.0.0.0/7 126.0.0.0/8 128.0.0.0/3 160.0.0.0/5 168.0.0.0/8 169.0.0.0/9 169.128.0.0/10 169.192.0.0/11 169.224.0.0/12 169.240.0.0/13 169.248.0.0/14 169.252.0.0/15 170.0.0.0/7 172.0.0.0/12 172.32.0.0/11 172.64.0.0/10 172.128.0.0/9 173.0.0.0/8 174.0.0.0/7 176.0.0.0/4 192.0.1.0/24 192.0.2.0/23 192.0.4.0/22 192.0.8.0/21 192.0.16.0/20 192.0.32.0/19 192.0.64.0/18 192.0.128.0/17 192.1.0.0/16 192.2.0.0/15 192.4.0.0/14 192.8.0.0/13 192.16.0.0/15 192.20.0.0/14 192.24.0.0/13 192.32.0.0/11 192.64.0.0/12 192.80.0.0/13 192.88.0.0/18 192.88.64.0/19 192.88.96.0/23 192.88.98.0/24 192.88.100.0/22 192.88.104.0/21 192.88.112.0/20 192.88.128.0/17 192.89.0.0/16 192.90.0.0/15 192.92.0.0/14 192.96.0.0/11 192.128.0.0/11 192.160.0.0/13 192.169.0.0/16 192.170.0.0/15 192.172.0.0/14 192.176.0.0/12 192.192.0.0/10 193.0.0.0/8 194.0.0.0/7 196.0.0.0/6 200.0.0.0/5 208.0.0.0/4

Private Prefixes

These are the prefixes which are reserved for use across private networks which may or may not have internet access. Note: All these are explicitly excluded from the public prefixes

10.0.0.0/8 172.16.0.0/12 192.168.0.0/16

Other Reserved Prefixes

These are the remaining prefixes which have been excluded from the public prefixes, please see the IANA documentation for their designated use. Note: All these are explicitly excluded from the public prefixes

0.0.0.0/8 127.0.0.0/8 169.254.0.0/16 192.0.0.0/24 192.18.0.0/15 192.88.99.0/24 224.0.0.0/2