What are the valid public ip address ranges

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.

• 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