...
nslookup -q=TXT _netblocks.google.com 8.8.8.8
64.18.0.0/20
64.233.160.0/19
66.102.0.0/20
66.249.80.0/20
72.14.192.0/18
74.125.0.0/16
108.177.8.0/21
173.194.0.0/16
207.126.144.0/20
209.85.128.0/17
216.58.192.0/19
216.239.32.0/19
nslookup -q=TXT _netblocks3.google.com 8.8.8.8
172.217.0.0/19
172.217.32.0/20
172.217.128.0/19
172.217.160.0/20
172.217.192.0/19
108.177.96.0/19
nslookup -q=TXT _cloud-netblocks1.googleusercontent.com 8.8.8.8
8.34.208.0/20
8.35.192.0/21
8.35.200.0/23
108.59.80.0/20
108.170.192.0/20
108.170.208.0/21
108.170.216.0/22
108.170.220.0/23
108.170.222.0/24
130.211.4.0/22
35.229.0.0/17
nslookup -q=TXT _cloud-netblocks2.googleusercontent.com 8.8.8.8
162.216.148.0/22
162.222.176.0/21
173.255.112.0/20
192.158.28.0/22
199.192.112.0/22
199.223.232.0/22
199.223.236.0/23
23.236.48.0/20
23.251.128.0/19
35.224.0.0/14
35.228.0.0/16
nslookup -q=TXT _cloud-netblocks3.googleusercontent.com 8.8.8.8
107.167.160.0/19
107.178.192.0/18
146.148.2.0/23
146.148.4.0/22
146.148.8.0/21
146.148.16.0/20
146.148.32.0/19
146.148.64.0/18
13035.211203.40.0/2217
35.203.0128.0/1718
35.203.128192.0/1819
35.203.240.0/20
nslookup -q=TXT _cloud-netblocks4.googleusercontent.com 8.8.8.8
130.211.8.0/21
130.211.16.0/20
130.211.32.0/19
130.211.64.0/18
130.211.128.0/17
104.154.0.0/15
104.196.0.0/14
208.68.108.0/23
35.184.0.0/14
35.188.0.0/15
35.206.64.0/18
35.202.0.0/16
nslookup -q=TXT _cloud-netblocks5.googleusercontent.com 8.8.8.8
35.190.0.0/17
35.190.128.0/18
35.190.192.0/19
35.190.224.0/20
35.192.0.0/14
35.196.0.0/15
35.198.0.0/16
35.199.0.0/17
35.199.128.0/18
35.200.0.0/15
35.204.0.0/16
IPv6 blocks
nslookup -q=TXT _netblocks2.google.com 8.8.8.8
2001:4860:4000::/36
2404:6800:4000::/36
2607:f8b0:4000::/36
2800:3f0:4000::/36
2a00:1450:4000::/36
2c0f:fb50:4000::/3615