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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.

Network72.167.232.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
72.167.232.0
Broadcast address
72.167.235.255
First usable
72.167.232.1
Last usable
72.167.235.254
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 48A7E800 · Integer 1218963456 to 1218964479
Reverse DNS zones
232.167.72.in-addr.arpa
233.167.72.in-addr.arpa
234.167.72.in-addr.arpa
235.167.72.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
Address01001000.10100111.11101000.0000000072.167.232.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network01001000.10100111.11101000.0000000072.167.232.0
Broadcast01001000.10100111.11101011.1111111172.167.235.255
Split into smaller subnets/32
/23 (2)/24 (4)/25 (8)/26 (16)/27 (32)/28 (64)/29 (128)/30 (256)/31 (512)/32 (1,024)

72.167.232.0/22 makes 1,024 subnets of /32; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
172.167.232.0/3272.167.232.0 to 72.167.232.0—1
272.167.232.1/3272.167.232.1 to 72.167.232.1—1
372.167.232.2/3272.167.232.2 to 72.167.232.2—1
472.167.232.3/3272.167.232.3 to 72.167.232.3—1
572.167.232.4/3272.167.232.4 to 72.167.232.4—1
672.167.232.5/3272.167.232.5 to 72.167.232.5—1
772.167.232.6/3272.167.232.6 to 72.167.232.6—1
872.167.232.7/3272.167.232.7 to 72.167.232.7—1
972.167.232.8/3272.167.232.8 to 72.167.232.8—1
1072.167.232.9/3272.167.232.9 to 72.167.232.9—1
1172.167.232.10/3272.167.232.10 to 72.167.232.10—1
1272.167.232.11/3272.167.232.11 to 72.167.232.11—1
1372.167.232.12/3272.167.232.12 to 72.167.232.12—1
1472.167.232.13/3272.167.232.13 to 72.167.232.13—1
1572.167.232.14/3272.167.232.14 to 72.167.232.14—1
1672.167.232.15/3272.167.232.15 to 72.167.232.15—1
1772.167.232.16/3272.167.232.16 to 72.167.232.16—1
1872.167.232.17/3272.167.232.17 to 72.167.232.17—1
1972.167.232.18/3272.167.232.18 to 72.167.232.18—1
2072.167.232.19/3272.167.232.19 to 72.167.232.19—1
2172.167.232.20/3272.167.232.20 to 72.167.232.20—1
2272.167.232.21/3272.167.232.21 to 72.167.232.21—1
2372.167.232.22/3272.167.232.22 to 72.167.232.22—1
2472.167.232.23/3272.167.232.23 to 72.167.232.23—1
2572.167.232.24/3272.167.232.24 to 72.167.232.24—1
2672.167.232.25/3272.167.232.25 to 72.167.232.25—1
2772.167.232.26/3272.167.232.26 to 72.167.232.26—1
2872.167.232.27/3272.167.232.27 to 72.167.232.27—1
2972.167.232.28/3272.167.232.28 to 72.167.232.28—1
3072.167.232.29/3272.167.232.29 to 72.167.232.29—1
3172.167.232.30/3272.167.232.30 to 72.167.232.30—1
3272.167.232.31/3272.167.232.31 to 72.167.232.31—1
3372.167.232.32/3272.167.232.32 to 72.167.232.32—1
3472.167.232.33/3272.167.232.33 to 72.167.232.33—1
3572.167.232.34/3272.167.232.34 to 72.167.232.34—1
3672.167.232.35/3272.167.232.35 to 72.167.232.35—1
3772.167.232.36/3272.167.232.36 to 72.167.232.36—1
3872.167.232.37/3272.167.232.37 to 72.167.232.37—1
3972.167.232.38/3272.167.232.38 to 72.167.232.38—1
4072.167.232.39/3272.167.232.39 to 72.167.232.39—1
4172.167.232.40/3272.167.232.40 to 72.167.232.40—1
4272.167.232.41/3272.167.232.41 to 72.167.232.41—1
4372.167.232.42/3272.167.232.42 to 72.167.232.42—1
4472.167.232.43/3272.167.232.43 to 72.167.232.43—1
4572.167.232.44/3272.167.232.44 to 72.167.232.44—1
4672.167.232.45/3272.167.232.45 to 72.167.232.45—1
4772.167.232.46/3272.167.232.46 to 72.167.232.46—1
4872.167.232.47/3272.167.232.47 to 72.167.232.47—1
4972.167.232.48/3272.167.232.48 to 72.167.232.48—1
5072.167.232.49/3272.167.232.49 to 72.167.232.49—1
5172.167.232.50/3272.167.232.50 to 72.167.232.50—1
5272.167.232.51/3272.167.232.51 to 72.167.232.51—1
5372.167.232.52/3272.167.232.52 to 72.167.232.52—1
5472.167.232.53/3272.167.232.53 to 72.167.232.53—1
5572.167.232.54/3272.167.232.54 to 72.167.232.54—1
5672.167.232.55/3272.167.232.55 to 72.167.232.55—1
5772.167.232.56/3272.167.232.56 to 72.167.232.56—1
5872.167.232.57/3272.167.232.57 to 72.167.232.57—1
5972.167.232.58/3272.167.232.58 to 72.167.232.58—1
6072.167.232.59/3272.167.232.59 to 72.167.232.59—1
6172.167.232.60/3272.167.232.60 to 72.167.232.60—1
6272.167.232.61/3272.167.232.61 to 72.167.232.61—1
6372.167.232.62/3272.167.232.62 to 72.167.232.62—1
6472.167.232.63/3272.167.232.63 to 72.167.232.63—1
6572.167.232.64/3272.167.232.64 to 72.167.232.64—1
6672.167.232.65/3272.167.232.65 to 72.167.232.65—1
6772.167.232.66/3272.167.232.66 to 72.167.232.66—1
6872.167.232.67/3272.167.232.67 to 72.167.232.67—1
6972.167.232.68/3272.167.232.68 to 72.167.232.68—1
7072.167.232.69/3272.167.232.69 to 72.167.232.69—1
7172.167.232.70/3272.167.232.70 to 72.167.232.70—1
7272.167.232.71/3272.167.232.71 to 72.167.232.71—1
7372.167.232.72/3272.167.232.72 to 72.167.232.72—1
7472.167.232.73/3272.167.232.73 to 72.167.232.73—1
7572.167.232.74/3272.167.232.74 to 72.167.232.74—1
7672.167.232.75/3272.167.232.75 to 72.167.232.75—1
7772.167.232.76/3272.167.232.76 to 72.167.232.76—1
7872.167.232.77/3272.167.232.77 to 72.167.232.77—1
7972.167.232.78/3272.167.232.78 to 72.167.232.78—1
8072.167.232.79/3272.167.232.79 to 72.167.232.79—1
8172.167.232.80/3272.167.232.80 to 72.167.232.80—1
8272.167.232.81/3272.167.232.81 to 72.167.232.81—1
8372.167.232.82/3272.167.232.82 to 72.167.232.82—1
8472.167.232.83/3272.167.232.83 to 72.167.232.83—1
8572.167.232.84/3272.167.232.84 to 72.167.232.84—1
8672.167.232.85/3272.167.232.85 to 72.167.232.85—1
8772.167.232.86/3272.167.232.86 to 72.167.232.86—1
8872.167.232.87/3272.167.232.87 to 72.167.232.87—1
8972.167.232.88/3272.167.232.88 to 72.167.232.88—1
9072.167.232.89/3272.167.232.89 to 72.167.232.89—1
9172.167.232.90/3272.167.232.90 to 72.167.232.90—1
9272.167.232.91/3272.167.232.91 to 72.167.232.91—1
9372.167.232.92/3272.167.232.92 to 72.167.232.92—1
9472.167.232.93/3272.167.232.93 to 72.167.232.93—1
9572.167.232.94/3272.167.232.94 to 72.167.232.94—1
9672.167.232.95/3272.167.232.95 to 72.167.232.95—1
9772.167.232.96/3272.167.232.96 to 72.167.232.96—1
9872.167.232.97/3272.167.232.97 to 72.167.232.97—1
9972.167.232.98/3272.167.232.98 to 72.167.232.98—1
10072.167.232.99/3272.167.232.99 to 72.167.232.99—1
10172.167.232.100/3272.167.232.100 to 72.167.232.100—1
10272.167.232.101/3272.167.232.101 to 72.167.232.101—1
10372.167.232.102/3272.167.232.102 to 72.167.232.102—1
10472.167.232.103/3272.167.232.103 to 72.167.232.103—1
10572.167.232.104/3272.167.232.104 to 72.167.232.104—1
10672.167.232.105/3272.167.232.105 to 72.167.232.105—1
10772.167.232.106/3272.167.232.106 to 72.167.232.106—1
10872.167.232.107/3272.167.232.107 to 72.167.232.107—1
10972.167.232.108/3272.167.232.108 to 72.167.232.108—1
11072.167.232.109/3272.167.232.109 to 72.167.232.109—1
11172.167.232.110/3272.167.232.110 to 72.167.232.110—1
11272.167.232.111/3272.167.232.111 to 72.167.232.111—1
11372.167.232.112/3272.167.232.112 to 72.167.232.112—1
11472.167.232.113/3272.167.232.113 to 72.167.232.113—1
11572.167.232.114/3272.167.232.114 to 72.167.232.114—1
11672.167.232.115/3272.167.232.115 to 72.167.232.115—1
11772.167.232.116/3272.167.232.116 to 72.167.232.116—1
11872.167.232.117/3272.167.232.117 to 72.167.232.117—1
11972.167.232.118/3272.167.232.118 to 72.167.232.118—1
12072.167.232.119/3272.167.232.119 to 72.167.232.119—1
12172.167.232.120/3272.167.232.120 to 72.167.232.120—1
12272.167.232.121/3272.167.232.121 to 72.167.232.121—1
12372.167.232.122/3272.167.232.122 to 72.167.232.122—1
12472.167.232.123/3272.167.232.123 to 72.167.232.123—1
12572.167.232.124/3272.167.232.124 to 72.167.232.124—1
12672.167.232.125/3272.167.232.125 to 72.167.232.125—1
12772.167.232.126/3272.167.232.126 to 72.167.232.126—1
12872.167.232.127/3272.167.232.127 to 72.167.232.127—1
12972.167.232.128/3272.167.232.128 to 72.167.232.128—1
13072.167.232.129/3272.167.232.129 to 72.167.232.129—1
13172.167.232.130/3272.167.232.130 to 72.167.232.130—1
13272.167.232.131/3272.167.232.131 to 72.167.232.131—1
13372.167.232.132/3272.167.232.132 to 72.167.232.132—1
13472.167.232.133/3272.167.232.133 to 72.167.232.133—1
13572.167.232.134/3272.167.232.134 to 72.167.232.134—1
13672.167.232.135/3272.167.232.135 to 72.167.232.135—1
13772.167.232.136/3272.167.232.136 to 72.167.232.136—1
13872.167.232.137/3272.167.232.137 to 72.167.232.137—1
13972.167.232.138/3272.167.232.138 to 72.167.232.138—1
14072.167.232.139/3272.167.232.139 to 72.167.232.139—1
14172.167.232.140/3272.167.232.140 to 72.167.232.140—1
14272.167.232.141/3272.167.232.141 to 72.167.232.141—1
14372.167.232.142/3272.167.232.142 to 72.167.232.142—1
14472.167.232.143/3272.167.232.143 to 72.167.232.143—1
14572.167.232.144/3272.167.232.144 to 72.167.232.144—1
14672.167.232.145/3272.167.232.145 to 72.167.232.145—1
14772.167.232.146/3272.167.232.146 to 72.167.232.146—1
14872.167.232.147/3272.167.232.147 to 72.167.232.147—1
14972.167.232.148/3272.167.232.148 to 72.167.232.148—1
15072.167.232.149/3272.167.232.149 to 72.167.232.149—1
15172.167.232.150/3272.167.232.150 to 72.167.232.150—1
15272.167.232.151/3272.167.232.151 to 72.167.232.151—1
15372.167.232.152/3272.167.232.152 to 72.167.232.152—1
15472.167.232.153/3272.167.232.153 to 72.167.232.153—1
15572.167.232.154/3272.167.232.154 to 72.167.232.154—1
15672.167.232.155/3272.167.232.155 to 72.167.232.155—1
15772.167.232.156/3272.167.232.156 to 72.167.232.156—1
15872.167.232.157/3272.167.232.157 to 72.167.232.157—1
15972.167.232.158/3272.167.232.158 to 72.167.232.158—1
16072.167.232.159/3272.167.232.159 to 72.167.232.159—1
16172.167.232.160/3272.167.232.160 to 72.167.232.160—1
16272.167.232.161/3272.167.232.161 to 72.167.232.161—1
16372.167.232.162/3272.167.232.162 to 72.167.232.162—1
16472.167.232.163/3272.167.232.163 to 72.167.232.163—1
16572.167.232.164/3272.167.232.164 to 72.167.232.164—1
16672.167.232.165/3272.167.232.165 to 72.167.232.165—1
16772.167.232.166/3272.167.232.166 to 72.167.232.166—1
16872.167.232.167/3272.167.232.167 to 72.167.232.167—1
16972.167.232.168/3272.167.232.168 to 72.167.232.168—1
17072.167.232.169/3272.167.232.169 to 72.167.232.169—1
17172.167.232.170/3272.167.232.170 to 72.167.232.170—1
17272.167.232.171/3272.167.232.171 to 72.167.232.171—1
17372.167.232.172/3272.167.232.172 to 72.167.232.172—1
17472.167.232.173/3272.167.232.173 to 72.167.232.173—1
17572.167.232.174/3272.167.232.174 to 72.167.232.174—1
17672.167.232.175/3272.167.232.175 to 72.167.232.175—1
17772.167.232.176/3272.167.232.176 to 72.167.232.176—1
17872.167.232.177/3272.167.232.177 to 72.167.232.177—1
17972.167.232.178/3272.167.232.178 to 72.167.232.178—1
18072.167.232.179/3272.167.232.179 to 72.167.232.179—1
18172.167.232.180/3272.167.232.180 to 72.167.232.180—1
18272.167.232.181/3272.167.232.181 to 72.167.232.181—1
18372.167.232.182/3272.167.232.182 to 72.167.232.182—1
18472.167.232.183/3272.167.232.183 to 72.167.232.183—1
18572.167.232.184/3272.167.232.184 to 72.167.232.184—1
18672.167.232.185/3272.167.232.185 to 72.167.232.185—1
18772.167.232.186/3272.167.232.186 to 72.167.232.186—1
18872.167.232.187/3272.167.232.187 to 72.167.232.187—1
18972.167.232.188/3272.167.232.188 to 72.167.232.188—1
19072.167.232.189/3272.167.232.189 to 72.167.232.189—1
19172.167.232.190/3272.167.232.190 to 72.167.232.190—1
19272.167.232.191/3272.167.232.191 to 72.167.232.191—1
19372.167.232.192/3272.167.232.192 to 72.167.232.192—1
19472.167.232.193/3272.167.232.193 to 72.167.232.193—1
19572.167.232.194/3272.167.232.194 to 72.167.232.194—1
19672.167.232.195/3272.167.232.195 to 72.167.232.195—1
19772.167.232.196/3272.167.232.196 to 72.167.232.196—1
19872.167.232.197/3272.167.232.197 to 72.167.232.197—1
19972.167.232.198/3272.167.232.198 to 72.167.232.198—1
20072.167.232.199/3272.167.232.199 to 72.167.232.199—1
20172.167.232.200/3272.167.232.200 to 72.167.232.200—1
20272.167.232.201/3272.167.232.201 to 72.167.232.201—1
20372.167.232.202/3272.167.232.202 to 72.167.232.202—1
20472.167.232.203/3272.167.232.203 to 72.167.232.203—1
20572.167.232.204/3272.167.232.204 to 72.167.232.204—1
20672.167.232.205/3272.167.232.205 to 72.167.232.205—1
20772.167.232.206/3272.167.232.206 to 72.167.232.206—1
20872.167.232.207/3272.167.232.207 to 72.167.232.207—1
20972.167.232.208/3272.167.232.208 to 72.167.232.208—1
21072.167.232.209/3272.167.232.209 to 72.167.232.209—1
21172.167.232.210/3272.167.232.210 to 72.167.232.210—1
21272.167.232.211/3272.167.232.211 to 72.167.232.211—1
21372.167.232.212/3272.167.232.212 to 72.167.232.212—1
21472.167.232.213/3272.167.232.213 to 72.167.232.213—1
21572.167.232.214/3272.167.232.214 to 72.167.232.214—1
21672.167.232.215/3272.167.232.215 to 72.167.232.215—1
21772.167.232.216/3272.167.232.216 to 72.167.232.216—1
21872.167.232.217/3272.167.232.217 to 72.167.232.217—1
21972.167.232.218/3272.167.232.218 to 72.167.232.218—1
22072.167.232.219/3272.167.232.219 to 72.167.232.219—1
22172.167.232.220/3272.167.232.220 to 72.167.232.220—1
22272.167.232.221/3272.167.232.221 to 72.167.232.221—1
22372.167.232.222/3272.167.232.222 to 72.167.232.222—1
22472.167.232.223/3272.167.232.223 to 72.167.232.223—1
22572.167.232.224/3272.167.232.224 to 72.167.232.224—1
22672.167.232.225/3272.167.232.225 to 72.167.232.225—1
22772.167.232.226/3272.167.232.226 to 72.167.232.226—1
22872.167.232.227/3272.167.232.227 to 72.167.232.227—1
22972.167.232.228/3272.167.232.228 to 72.167.232.228—1
23072.167.232.229/3272.167.232.229 to 72.167.232.229—1
23172.167.232.230/3272.167.232.230 to 72.167.232.230—1
23272.167.232.231/3272.167.232.231 to 72.167.232.231—1
23372.167.232.232/3272.167.232.232 to 72.167.232.232—1
23472.167.232.233/3272.167.232.233 to 72.167.232.233—1
23572.167.232.234/3272.167.232.234 to 72.167.232.234—1
23672.167.232.235/3272.167.232.235 to 72.167.232.235—1
23772.167.232.236/3272.167.232.236 to 72.167.232.236—1
23872.167.232.237/3272.167.232.237 to 72.167.232.237—1
23972.167.232.238/3272.167.232.238 to 72.167.232.238—1
24072.167.232.239/3272.167.232.239 to 72.167.232.239—1
24172.167.232.240/3272.167.232.240 to 72.167.232.240—1
24272.167.232.241/3272.167.232.241 to 72.167.232.241—1
24372.167.232.242/3272.167.232.242 to 72.167.232.242—1
24472.167.232.243/3272.167.232.243 to 72.167.232.243—1
24572.167.232.244/3272.167.232.244 to 72.167.232.244—1
24672.167.232.245/3272.167.232.245 to 72.167.232.245—1
24772.167.232.246/3272.167.232.246 to 72.167.232.246—1
24872.167.232.247/3272.167.232.247 to 72.167.232.247—1
24972.167.232.248/3272.167.232.248 to 72.167.232.248—1
25072.167.232.249/3272.167.232.249 to 72.167.232.249—1
25172.167.232.250/3272.167.232.250 to 72.167.232.250—1
25272.167.232.251/3272.167.232.251 to 72.167.232.251—1
25372.167.232.252/3272.167.232.252 to 72.167.232.252—1
25472.167.232.253/3272.167.232.253 to 72.167.232.253—1
25572.167.232.254/3272.167.232.254 to 72.167.232.254—1
25672.167.232.255/3272.167.232.255 to 72.167.232.255—1

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

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.