What are the valid public IP address ranges?

Question

There are a number of lists on the web that define all valid public IP addresses ranges but they don't seem to be very accurate.

The most common list Ive found is show below. This list however doesn't include addresses in 191.236.x.x even though there are public web servers in that range.

Is there a definitive and correct list of valid public IP address ranges?

• 1.0.0.0 - 9.255.255.255
• 11.0.0.0 - 126.255.255.255
• 129.0.0.0 - 169.253.255.255
• 169.255.0.0 - 172.15.255.255
• 172.32.0.0 - 191.0.1.255
• 192.0.3.0 - 192.88.98.255
• 192.88.100.0 - 192.167.255.255
• 192.169.0.0 - 198.17.255.255
• 198.20.0.0 - 223.255.255.255

Answer 1

IANA provides standards on this subject. For IPv4, here is what they have in their "special purpose address registry". Meaning, for our purposes, anything in these address blocks shouldn't be assigned because they shouldn't be routable "publicly".

0.0.0.0/8
10.0.0.0/8
100.64.0.0/10
127.0.0.0/8
169.254.0.0/16
172.16.0.0/12
192.0.0.0/24
192.0.0.0/29
192.0.0.8/32
192.0.0.9/32
192.0.0.170/32
192.0.0.171/32
192.0.2.0/24
192.31.196.0/24
192.52.193.0/24
192.88.99.0/24
192.168.0.0/16
192.175.48.0/24
198.18.0.0/15
198.51.100.0/24
203.0.113.0/24
240.0.0.0/4
255.255.255.255/32
Also to be considered, multicast addresses subnet:
224.0.0.0/4

This is more consistent with the example you provided above.

If you don't understand CIDR notation, you can convert them to ranges here.

Answer 2

• 1.0.0.0-9.255.255.255
• 11.0.0.0-100.63.255.255
• 100.128.0.0-126.255.255.255
• 128.0.0.0-169.253.255.255
• 169.255.0.0-172.15.255.255
• 172.32.0.0-191.255.255.255
• 192.0.1.0/24
• 192.0.3.0-192.88.98.255
• 192.88.100.0-192.167.255.255
• 192.169.0.0-198.17.255.255
• 198.20.0.0-198.51.99.255
• 198.51.101.0-203.0.112.255
• 203.0.114.0-223.255.255.255

Answer 3

Combining the lists from BrianC and hmuller I figured that 3 ranges do overlap:

• 192.31.196.0/24
• 192.52.193.0/24
• 192.175.48.0/24

In my combined list, they are considered as not valid:

CIDR             First IP      Last IP          
0.0.0.0/8        0.0.0.0       0.255.255.255    Not valid
                 1.0.0.0       9.255.255.255    Valid
10.0.0.0/8       10.0.0.0      10.255.255.255   Not valid
                 11.0.0.0      100.63.255.255   Valid
100.64.0.0/10    100.64.0.0    100.127.255.255  Not valid
                 100.128.0.0   126.255.255.255  Valid
127.0.0.0/8      127.0.0.0     127.255.255.255  Not valid
                 128.0.0.0     169.253.255.255  Valid
169.254.0.0/16   169.254.0.0   169.254.255.255  Not valid
                 169.255.0.0   172.15.255.255   Valid
172.16.0.0/12    172.16.0.0    172.31.255.255   Not valid
                 172.32.0.0    191.255.255.255  Valid
192.0.0.0/24     192.0.0.0     192.0.0.255      Not valid
192.0.1.0/24     192.0.1.0     192.0.1.255      Valid
192.0.2.0/24     192.0.2.0     192.0.2.255      Not valid
                 192.0.3.0     192.31.195.255   Valid
192.31.196.0/24  192.31.196.0  192.31.196.255   Not valid
                 192.31.197.0  192.52.192.255   Valid
192.52.193.0/24  192.52.193.0  192.52.193.255   Not valid
                 192.52.194.0  192.88.98.255    Valid
192.88.99.0/24   192.88.99.0   192.88.99.255    Not valid
                 192.88.100.0  192.167.255.255  Valid
192.168.0.0/16   192.168.0.0   192.168.255.255  Not valid
                 192.169.0.0   192.175.47.255   Valid
192.175.48.0/24  192.175.48.0  192.175.48.255   Not valid
                 192.175.49.0  198.17.255.255   Valid
198.18.0.0/15    198.18.0.0    198.19.255.255   Not valid
                 198.20.0.0    198.51.99.255    Valid
198.51.100.0/24  198.51.100.0  198.51.100.255   Not valid
                 198.51.101.0  203.0.112.255    Valid
203.0.113.0/24   203.0.113.0   203.0.113.255    Not valid
                 203.0.114.0   223.255.255.255  Valid
224.0.0.0/4      224.0.0.0     239.255.255.255  Not valid
240.0.0.0/4      240.0.0.0     255.255.255.255  Not valid

Answer 4

Rangos de redes públicas

• 1.0.0.0 - 9.255.255.255
• 11.0.0.0 - 126.255.255.255
• 129.0.0.0 - 169.253.255.255
• 169.255.0.0 - 172.15.255.255
• 172.32.0.0 - 191.0.1.255
• 192.0.3.0 - 192.88.98.255
• 192.88.100.0 - 192.167.255.255
• 192.169.0.0 - 198.17.255.255
• 198.20.0.0 - 223.255.255.255

RANGOS DE REDES PUBLICAS DESDE AQUI

1.0.0.0/5 > 7.255.255.255
8.0.0.0/7 > 9.255.255.255
11.0.0.0/2 > 63.255.255.255
64.0.0.0/3 > 95.255.255.255
96.0.0.0/4 > 111.255.255.255
112.0.0.0/5 > 119.255.255.255
120.0.0.0/6 > 123.255.255.255
124.0.0.0/7 > 125.255.255.255
126.0.0.0/8 > 126.255.255.255
129.0.0.0/3 > 159.255.255.255
160.0.0.0/5 > 167.255.255.255
168.0.0.0/8 > 168.255.255.255
169.0.0.0/9 > 169.127.255.255
169.128.0.0/10 > 169.191.255.255
169.192.0.0/11 > 169.223.255.255
169.224.0.0/12 > 169.239.255.255
169.240.0.0/13 > 169.247.255.255
169.248.0.0/14 > 169.251.255.255
169.252.0.0/15 > 169.253.255.255
169.255.0.0/6 > 171.255.255.255
172.0.0.0/12 > 172.15.255.255
172.32.0.0/4 > 175.255.255.255
176.0.0.0/5 > 183.255.255.255
184.0.0.0/6 > 187.255.255.255
188.0.0.0/7 > 189.255.255.255
190.0.0.0/8 > 190.255.255.255
191.0.0.0/23 > 191.0.1.255
192.0.3.0/10 > 192.63.255.255
192.64.0.0/12 > 192.79.255.255
192.80.0.0/13 > 192.87.255.255
192.88.0.0/18 > 192.88.63.255
192.88.64.0/19 > 192.88.95.255
192.88.96.0/23 > 192.88.97.255
192.88.98.0/24 > 192.88.98.255
192.88.100.0/9 > 192.127.255.255
192.128.0.0/11 > 192.159.255.255
192.160.0.0/13 > 192.167.255.255
192.169.0.0/6 > 195.255.255.255
196.0.0.0/7 > 197.255.255.255
198.0.0.0/12 > 198.15.255.255
198.16.0.0/15 > 198.17.255.255
198.20.0.0/3 > 223.255.255.255

I just made it manually in case someone need it.

Answer 5

All IP address from 1 to 191 excluding the RFC1918 private addresses below are assigned for Public IPs.:

RFC1918 - Private address alocation:

• 10.0.0.0 - 10.255.255.255 (10/8 prefix)
• 172.16.0.0 - 172.31.255.255 (172.16/12 prefix)
• 192.168.0.0 - 192.168.255.255 (192.168/16 prefix)