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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Network72.167.4.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
72.167.4.0
Broadcast address
72.167.7.255
First usable
72.167.4.1
Last usable
72.167.7.254
Usable hosts
1,022 (1,024 less the network and broadcast addresses)
Subnet mask
255.255.252.0
Wildcard mask
0.0.3.255 (Cisco ACLs, OSPF)
Prefix length
/22
Type
Public public
Old class
A (default /8)
As numbers
Hex 48A70400 · Integer 1218905088 to 1218906111
Reverse DNS zones
4.167.72.in-addr.arpa
5.167.72.in-addr.arpa
6.167.72.in-addr.arpa
7.167.72.in-addr.arpa
/22 is not on a 8-bit boundary, so it takes 4 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01001000.10100111.00000100.0000000072.167.4.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network01001000.10100111.00000100.0000000072.167.4.0
Broadcast01001000.10100111.00000111.1111111172.167.7.255
Split into smaller subnets/30

72.167.4.0/22 makes 256 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
172.167.4.0/3072.167.4.1 to 72.167.4.272.167.4.32
272.167.4.4/3072.167.4.5 to 72.167.4.672.167.4.72
372.167.4.8/3072.167.4.9 to 72.167.4.1072.167.4.112
472.167.4.12/3072.167.4.13 to 72.167.4.1472.167.4.152
572.167.4.16/3072.167.4.17 to 72.167.4.1872.167.4.192
672.167.4.20/3072.167.4.21 to 72.167.4.2272.167.4.232
772.167.4.24/3072.167.4.25 to 72.167.4.2672.167.4.272
872.167.4.28/3072.167.4.29 to 72.167.4.3072.167.4.312
972.167.4.32/3072.167.4.33 to 72.167.4.3472.167.4.352
1072.167.4.36/3072.167.4.37 to 72.167.4.3872.167.4.392
1172.167.4.40/3072.167.4.41 to 72.167.4.4272.167.4.432
1272.167.4.44/3072.167.4.45 to 72.167.4.4672.167.4.472
1372.167.4.48/3072.167.4.49 to 72.167.4.5072.167.4.512
1472.167.4.52/3072.167.4.53 to 72.167.4.5472.167.4.552
1572.167.4.56/3072.167.4.57 to 72.167.4.5872.167.4.592
1672.167.4.60/3072.167.4.61 to 72.167.4.6272.167.4.632
1772.167.4.64/3072.167.4.65 to 72.167.4.6672.167.4.672
1872.167.4.68/3072.167.4.69 to 72.167.4.7072.167.4.712
1972.167.4.72/3072.167.4.73 to 72.167.4.7472.167.4.752
2072.167.4.76/3072.167.4.77 to 72.167.4.7872.167.4.792
2172.167.4.80/3072.167.4.81 to 72.167.4.8272.167.4.832
2272.167.4.84/3072.167.4.85 to 72.167.4.8672.167.4.872
2372.167.4.88/3072.167.4.89 to 72.167.4.9072.167.4.912
2472.167.4.92/3072.167.4.93 to 72.167.4.9472.167.4.952
2572.167.4.96/3072.167.4.97 to 72.167.4.9872.167.4.992
2672.167.4.100/3072.167.4.101 to 72.167.4.10272.167.4.1032
2772.167.4.104/3072.167.4.105 to 72.167.4.10672.167.4.1072
2872.167.4.108/3072.167.4.109 to 72.167.4.11072.167.4.1112
2972.167.4.112/3072.167.4.113 to 72.167.4.11472.167.4.1152
3072.167.4.116/3072.167.4.117 to 72.167.4.11872.167.4.1192
3172.167.4.120/3072.167.4.121 to 72.167.4.12272.167.4.1232
3272.167.4.124/3072.167.4.125 to 72.167.4.12672.167.4.1272
3372.167.4.128/3072.167.4.129 to 72.167.4.13072.167.4.1312
3472.167.4.132/3072.167.4.133 to 72.167.4.13472.167.4.1352
3572.167.4.136/3072.167.4.137 to 72.167.4.13872.167.4.1392
3672.167.4.140/3072.167.4.141 to 72.167.4.14272.167.4.1432
3772.167.4.144/3072.167.4.145 to 72.167.4.14672.167.4.1472
3872.167.4.148/3072.167.4.149 to 72.167.4.15072.167.4.1512
3972.167.4.152/3072.167.4.153 to 72.167.4.15472.167.4.1552
4072.167.4.156/3072.167.4.157 to 72.167.4.15872.167.4.1592
4172.167.4.160/3072.167.4.161 to 72.167.4.16272.167.4.1632
4272.167.4.164/3072.167.4.165 to 72.167.4.16672.167.4.1672
4372.167.4.168/3072.167.4.169 to 72.167.4.17072.167.4.1712
4472.167.4.172/3072.167.4.173 to 72.167.4.17472.167.4.1752
4572.167.4.176/3072.167.4.177 to 72.167.4.17872.167.4.1792
4672.167.4.180/3072.167.4.181 to 72.167.4.18272.167.4.1832
4772.167.4.184/3072.167.4.185 to 72.167.4.18672.167.4.1872
4872.167.4.188/3072.167.4.189 to 72.167.4.19072.167.4.1912
4972.167.4.192/3072.167.4.193 to 72.167.4.19472.167.4.1952
5072.167.4.196/3072.167.4.197 to 72.167.4.19872.167.4.1992
5172.167.4.200/3072.167.4.201 to 72.167.4.20272.167.4.2032
5272.167.4.204/3072.167.4.205 to 72.167.4.20672.167.4.2072
5372.167.4.208/3072.167.4.209 to 72.167.4.21072.167.4.2112
5472.167.4.212/3072.167.4.213 to 72.167.4.21472.167.4.2152
5572.167.4.216/3072.167.4.217 to 72.167.4.21872.167.4.2192
5672.167.4.220/3072.167.4.221 to 72.167.4.22272.167.4.2232
5772.167.4.224/3072.167.4.225 to 72.167.4.22672.167.4.2272
5872.167.4.228/3072.167.4.229 to 72.167.4.23072.167.4.2312
5972.167.4.232/3072.167.4.233 to 72.167.4.23472.167.4.2352
6072.167.4.236/3072.167.4.237 to 72.167.4.23872.167.4.2392
6172.167.4.240/3072.167.4.241 to 72.167.4.24272.167.4.2432
6272.167.4.244/3072.167.4.245 to 72.167.4.24672.167.4.2472
6372.167.4.248/3072.167.4.249 to 72.167.4.25072.167.4.2512
6472.167.4.252/3072.167.4.253 to 72.167.4.25472.167.4.2552
6572.167.5.0/3072.167.5.1 to 72.167.5.272.167.5.32
6672.167.5.4/3072.167.5.5 to 72.167.5.672.167.5.72
6772.167.5.8/3072.167.5.9 to 72.167.5.1072.167.5.112
6872.167.5.12/3072.167.5.13 to 72.167.5.1472.167.5.152
6972.167.5.16/3072.167.5.17 to 72.167.5.1872.167.5.192
7072.167.5.20/3072.167.5.21 to 72.167.5.2272.167.5.232
7172.167.5.24/3072.167.5.25 to 72.167.5.2672.167.5.272
7272.167.5.28/3072.167.5.29 to 72.167.5.3072.167.5.312
7372.167.5.32/3072.167.5.33 to 72.167.5.3472.167.5.352
7472.167.5.36/3072.167.5.37 to 72.167.5.3872.167.5.392
7572.167.5.40/3072.167.5.41 to 72.167.5.4272.167.5.432
7672.167.5.44/3072.167.5.45 to 72.167.5.4672.167.5.472
7772.167.5.48/3072.167.5.49 to 72.167.5.5072.167.5.512
7872.167.5.52/3072.167.5.53 to 72.167.5.5472.167.5.552
7972.167.5.56/3072.167.5.57 to 72.167.5.5872.167.5.592
8072.167.5.60/3072.167.5.61 to 72.167.5.6272.167.5.632
8172.167.5.64/3072.167.5.65 to 72.167.5.6672.167.5.672
8272.167.5.68/3072.167.5.69 to 72.167.5.7072.167.5.712
8372.167.5.72/3072.167.5.73 to 72.167.5.7472.167.5.752
8472.167.5.76/3072.167.5.77 to 72.167.5.7872.167.5.792
8572.167.5.80/3072.167.5.81 to 72.167.5.8272.167.5.832
8672.167.5.84/3072.167.5.85 to 72.167.5.8672.167.5.872
8772.167.5.88/3072.167.5.89 to 72.167.5.9072.167.5.912
8872.167.5.92/3072.167.5.93 to 72.167.5.9472.167.5.952
8972.167.5.96/3072.167.5.97 to 72.167.5.9872.167.5.992
9072.167.5.100/3072.167.5.101 to 72.167.5.10272.167.5.1032
9172.167.5.104/3072.167.5.105 to 72.167.5.10672.167.5.1072
9272.167.5.108/3072.167.5.109 to 72.167.5.11072.167.5.1112
9372.167.5.112/3072.167.5.113 to 72.167.5.11472.167.5.1152
9472.167.5.116/3072.167.5.117 to 72.167.5.11872.167.5.1192
9572.167.5.120/3072.167.5.121 to 72.167.5.12272.167.5.1232
9672.167.5.124/3072.167.5.125 to 72.167.5.12672.167.5.1272
9772.167.5.128/3072.167.5.129 to 72.167.5.13072.167.5.1312
9872.167.5.132/3072.167.5.133 to 72.167.5.13472.167.5.1352
9972.167.5.136/3072.167.5.137 to 72.167.5.13872.167.5.1392
10072.167.5.140/3072.167.5.141 to 72.167.5.14272.167.5.1432
10172.167.5.144/3072.167.5.145 to 72.167.5.14672.167.5.1472
10272.167.5.148/3072.167.5.149 to 72.167.5.15072.167.5.1512
10372.167.5.152/3072.167.5.153 to 72.167.5.15472.167.5.1552
10472.167.5.156/3072.167.5.157 to 72.167.5.15872.167.5.1592
10572.167.5.160/3072.167.5.161 to 72.167.5.16272.167.5.1632
10672.167.5.164/3072.167.5.165 to 72.167.5.16672.167.5.1672
10772.167.5.168/3072.167.5.169 to 72.167.5.17072.167.5.1712
10872.167.5.172/3072.167.5.173 to 72.167.5.17472.167.5.1752
10972.167.5.176/3072.167.5.177 to 72.167.5.17872.167.5.1792
11072.167.5.180/3072.167.5.181 to 72.167.5.18272.167.5.1832
11172.167.5.184/3072.167.5.185 to 72.167.5.18672.167.5.1872
11272.167.5.188/3072.167.5.189 to 72.167.5.19072.167.5.1912
11372.167.5.192/3072.167.5.193 to 72.167.5.19472.167.5.1952
11472.167.5.196/3072.167.5.197 to 72.167.5.19872.167.5.1992
11572.167.5.200/3072.167.5.201 to 72.167.5.20272.167.5.2032
11672.167.5.204/3072.167.5.205 to 72.167.5.20672.167.5.2072
11772.167.5.208/3072.167.5.209 to 72.167.5.21072.167.5.2112
11872.167.5.212/3072.167.5.213 to 72.167.5.21472.167.5.2152
11972.167.5.216/3072.167.5.217 to 72.167.5.21872.167.5.2192
12072.167.5.220/3072.167.5.221 to 72.167.5.22272.167.5.2232
12172.167.5.224/3072.167.5.225 to 72.167.5.22672.167.5.2272
12272.167.5.228/3072.167.5.229 to 72.167.5.23072.167.5.2312
12372.167.5.232/3072.167.5.233 to 72.167.5.23472.167.5.2352
12472.167.5.236/3072.167.5.237 to 72.167.5.23872.167.5.2392
12572.167.5.240/3072.167.5.241 to 72.167.5.24272.167.5.2432
12672.167.5.244/3072.167.5.245 to 72.167.5.24672.167.5.2472
12772.167.5.248/3072.167.5.249 to 72.167.5.25072.167.5.2512
12872.167.5.252/3072.167.5.253 to 72.167.5.25472.167.5.2552
12972.167.6.0/3072.167.6.1 to 72.167.6.272.167.6.32
13072.167.6.4/3072.167.6.5 to 72.167.6.672.167.6.72
13172.167.6.8/3072.167.6.9 to 72.167.6.1072.167.6.112
13272.167.6.12/3072.167.6.13 to 72.167.6.1472.167.6.152
13372.167.6.16/3072.167.6.17 to 72.167.6.1872.167.6.192
13472.167.6.20/3072.167.6.21 to 72.167.6.2272.167.6.232
13572.167.6.24/3072.167.6.25 to 72.167.6.2672.167.6.272
13672.167.6.28/3072.167.6.29 to 72.167.6.3072.167.6.312
13772.167.6.32/3072.167.6.33 to 72.167.6.3472.167.6.352
13872.167.6.36/3072.167.6.37 to 72.167.6.3872.167.6.392
13972.167.6.40/3072.167.6.41 to 72.167.6.4272.167.6.432
14072.167.6.44/3072.167.6.45 to 72.167.6.4672.167.6.472
14172.167.6.48/3072.167.6.49 to 72.167.6.5072.167.6.512
14272.167.6.52/3072.167.6.53 to 72.167.6.5472.167.6.552
14372.167.6.56/3072.167.6.57 to 72.167.6.5872.167.6.592
14472.167.6.60/3072.167.6.61 to 72.167.6.6272.167.6.632
14572.167.6.64/3072.167.6.65 to 72.167.6.6672.167.6.672
14672.167.6.68/3072.167.6.69 to 72.167.6.7072.167.6.712
14772.167.6.72/3072.167.6.73 to 72.167.6.7472.167.6.752
14872.167.6.76/3072.167.6.77 to 72.167.6.7872.167.6.792
14972.167.6.80/3072.167.6.81 to 72.167.6.8272.167.6.832
15072.167.6.84/3072.167.6.85 to 72.167.6.8672.167.6.872
15172.167.6.88/3072.167.6.89 to 72.167.6.9072.167.6.912
15272.167.6.92/3072.167.6.93 to 72.167.6.9472.167.6.952
15372.167.6.96/3072.167.6.97 to 72.167.6.9872.167.6.992
15472.167.6.100/3072.167.6.101 to 72.167.6.10272.167.6.1032
15572.167.6.104/3072.167.6.105 to 72.167.6.10672.167.6.1072
15672.167.6.108/3072.167.6.109 to 72.167.6.11072.167.6.1112
15772.167.6.112/3072.167.6.113 to 72.167.6.11472.167.6.1152
15872.167.6.116/3072.167.6.117 to 72.167.6.11872.167.6.1192
15972.167.6.120/3072.167.6.121 to 72.167.6.12272.167.6.1232
16072.167.6.124/3072.167.6.125 to 72.167.6.12672.167.6.1272
16172.167.6.128/3072.167.6.129 to 72.167.6.13072.167.6.1312
16272.167.6.132/3072.167.6.133 to 72.167.6.13472.167.6.1352
16372.167.6.136/3072.167.6.137 to 72.167.6.13872.167.6.1392
16472.167.6.140/3072.167.6.141 to 72.167.6.14272.167.6.1432
16572.167.6.144/3072.167.6.145 to 72.167.6.14672.167.6.1472
16672.167.6.148/3072.167.6.149 to 72.167.6.15072.167.6.1512
16772.167.6.152/3072.167.6.153 to 72.167.6.15472.167.6.1552
16872.167.6.156/3072.167.6.157 to 72.167.6.15872.167.6.1592
16972.167.6.160/3072.167.6.161 to 72.167.6.16272.167.6.1632
17072.167.6.164/3072.167.6.165 to 72.167.6.16672.167.6.1672
17172.167.6.168/3072.167.6.169 to 72.167.6.17072.167.6.1712
17272.167.6.172/3072.167.6.173 to 72.167.6.17472.167.6.1752
17372.167.6.176/3072.167.6.177 to 72.167.6.17872.167.6.1792
17472.167.6.180/3072.167.6.181 to 72.167.6.18272.167.6.1832
17572.167.6.184/3072.167.6.185 to 72.167.6.18672.167.6.1872
17672.167.6.188/3072.167.6.189 to 72.167.6.19072.167.6.1912
17772.167.6.192/3072.167.6.193 to 72.167.6.19472.167.6.1952
17872.167.6.196/3072.167.6.197 to 72.167.6.19872.167.6.1992
17972.167.6.200/3072.167.6.201 to 72.167.6.20272.167.6.2032
18072.167.6.204/3072.167.6.205 to 72.167.6.20672.167.6.2072
18172.167.6.208/3072.167.6.209 to 72.167.6.21072.167.6.2112
18272.167.6.212/3072.167.6.213 to 72.167.6.21472.167.6.2152
18372.167.6.216/3072.167.6.217 to 72.167.6.21872.167.6.2192
18472.167.6.220/3072.167.6.221 to 72.167.6.22272.167.6.2232
18572.167.6.224/3072.167.6.225 to 72.167.6.22672.167.6.2272
18672.167.6.228/3072.167.6.229 to 72.167.6.23072.167.6.2312
18772.167.6.232/3072.167.6.233 to 72.167.6.23472.167.6.2352
18872.167.6.236/3072.167.6.237 to 72.167.6.23872.167.6.2392
18972.167.6.240/3072.167.6.241 to 72.167.6.24272.167.6.2432
19072.167.6.244/3072.167.6.245 to 72.167.6.24672.167.6.2472
19172.167.6.248/3072.167.6.249 to 72.167.6.25072.167.6.2512
19272.167.6.252/3072.167.6.253 to 72.167.6.25472.167.6.2552
19372.167.7.0/3072.167.7.1 to 72.167.7.272.167.7.32
19472.167.7.4/3072.167.7.5 to 72.167.7.672.167.7.72
19572.167.7.8/3072.167.7.9 to 72.167.7.1072.167.7.112
19672.167.7.12/3072.167.7.13 to 72.167.7.1472.167.7.152
19772.167.7.16/3072.167.7.17 to 72.167.7.1872.167.7.192
19872.167.7.20/3072.167.7.21 to 72.167.7.2272.167.7.232
19972.167.7.24/3072.167.7.25 to 72.167.7.2672.167.7.272
20072.167.7.28/3072.167.7.29 to 72.167.7.3072.167.7.312
20172.167.7.32/3072.167.7.33 to 72.167.7.3472.167.7.352
20272.167.7.36/3072.167.7.37 to 72.167.7.3872.167.7.392
20372.167.7.40/3072.167.7.41 to 72.167.7.4272.167.7.432
20472.167.7.44/3072.167.7.45 to 72.167.7.4672.167.7.472
20572.167.7.48/3072.167.7.49 to 72.167.7.5072.167.7.512
20672.167.7.52/3072.167.7.53 to 72.167.7.5472.167.7.552
20772.167.7.56/3072.167.7.57 to 72.167.7.5872.167.7.592
20872.167.7.60/3072.167.7.61 to 72.167.7.6272.167.7.632
20972.167.7.64/3072.167.7.65 to 72.167.7.6672.167.7.672
21072.167.7.68/3072.167.7.69 to 72.167.7.7072.167.7.712
21172.167.7.72/3072.167.7.73 to 72.167.7.7472.167.7.752
21272.167.7.76/3072.167.7.77 to 72.167.7.7872.167.7.792
21372.167.7.80/3072.167.7.81 to 72.167.7.8272.167.7.832
21472.167.7.84/3072.167.7.85 to 72.167.7.8672.167.7.872
21572.167.7.88/3072.167.7.89 to 72.167.7.9072.167.7.912
21672.167.7.92/3072.167.7.93 to 72.167.7.9472.167.7.952
21772.167.7.96/3072.167.7.97 to 72.167.7.9872.167.7.992
21872.167.7.100/3072.167.7.101 to 72.167.7.10272.167.7.1032
21972.167.7.104/3072.167.7.105 to 72.167.7.10672.167.7.1072
22072.167.7.108/3072.167.7.109 to 72.167.7.11072.167.7.1112
22172.167.7.112/3072.167.7.113 to 72.167.7.11472.167.7.1152
22272.167.7.116/3072.167.7.117 to 72.167.7.11872.167.7.1192
22372.167.7.120/3072.167.7.121 to 72.167.7.12272.167.7.1232
22472.167.7.124/3072.167.7.125 to 72.167.7.12672.167.7.1272
22572.167.7.128/3072.167.7.129 to 72.167.7.13072.167.7.1312
22672.167.7.132/3072.167.7.133 to 72.167.7.13472.167.7.1352
22772.167.7.136/3072.167.7.137 to 72.167.7.13872.167.7.1392
22872.167.7.140/3072.167.7.141 to 72.167.7.14272.167.7.1432
22972.167.7.144/3072.167.7.145 to 72.167.7.14672.167.7.1472
23072.167.7.148/3072.167.7.149 to 72.167.7.15072.167.7.1512
23172.167.7.152/3072.167.7.153 to 72.167.7.15472.167.7.1552
23272.167.7.156/3072.167.7.157 to 72.167.7.15872.167.7.1592
23372.167.7.160/3072.167.7.161 to 72.167.7.16272.167.7.1632
23472.167.7.164/3072.167.7.165 to 72.167.7.16672.167.7.1672
23572.167.7.168/3072.167.7.169 to 72.167.7.17072.167.7.1712
23672.167.7.172/3072.167.7.173 to 72.167.7.17472.167.7.1752
23772.167.7.176/3072.167.7.177 to 72.167.7.17872.167.7.1792
23872.167.7.180/3072.167.7.181 to 72.167.7.18272.167.7.1832
23972.167.7.184/3072.167.7.185 to 72.167.7.18672.167.7.1872
24072.167.7.188/3072.167.7.189 to 72.167.7.19072.167.7.1912
24172.167.7.192/3072.167.7.193 to 72.167.7.19472.167.7.1952
24272.167.7.196/3072.167.7.197 to 72.167.7.19872.167.7.1992
24372.167.7.200/3072.167.7.201 to 72.167.7.20272.167.7.2032
24472.167.7.204/3072.167.7.205 to 72.167.7.20672.167.7.2072
24572.167.7.208/3072.167.7.209 to 72.167.7.21072.167.7.2112
24672.167.7.212/3072.167.7.213 to 72.167.7.21472.167.7.2152
24772.167.7.216/3072.167.7.217 to 72.167.7.21872.167.7.2192
24872.167.7.220/3072.167.7.221 to 72.167.7.22272.167.7.2232
24972.167.7.224/3072.167.7.225 to 72.167.7.22672.167.7.2272
25072.167.7.228/3072.167.7.229 to 72.167.7.23072.167.7.2312
25172.167.7.232/3072.167.7.233 to 72.167.7.23472.167.7.2352
25272.167.7.236/3072.167.7.237 to 72.167.7.23872.167.7.2392
25372.167.7.240/3072.167.7.241 to 72.167.7.24272.167.7.2432
25472.167.7.244/3072.167.7.245 to 72.167.7.24672.167.7.2472
25572.167.7.248/3072.167.7.249 to 72.167.7.25072.167.7.2512
25672.167.7.252/3072.167.7.253 to 72.167.7.25472.167.7.2552

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses