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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.

Network90.167.72.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
90.167.72.0
Broadcast address
90.167.75.255
First usable
90.167.72.1
Last usable
90.167.75.254
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 5AA74800 · Integer 1520912384 to 1520913407
Reverse DNS zones
72.167.90.in-addr.arpa
73.167.90.in-addr.arpa
74.167.90.in-addr.arpa
75.167.90.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
Address01011010.10100111.01001000.0000000090.167.72.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network01011010.10100111.01001000.0000000090.167.72.0
Broadcast01011010.10100111.01001011.1111111190.167.75.255
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)

90.167.72.0/22 makes 1,024 subnets of /32; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
190.167.72.0/3290.167.72.0 to 90.167.72.0—1
290.167.72.1/3290.167.72.1 to 90.167.72.1—1
390.167.72.2/3290.167.72.2 to 90.167.72.2—1
490.167.72.3/3290.167.72.3 to 90.167.72.3—1
590.167.72.4/3290.167.72.4 to 90.167.72.4—1
690.167.72.5/3290.167.72.5 to 90.167.72.5—1
790.167.72.6/3290.167.72.6 to 90.167.72.6—1
890.167.72.7/3290.167.72.7 to 90.167.72.7—1
990.167.72.8/3290.167.72.8 to 90.167.72.8—1
1090.167.72.9/3290.167.72.9 to 90.167.72.9—1
1190.167.72.10/3290.167.72.10 to 90.167.72.10—1
1290.167.72.11/3290.167.72.11 to 90.167.72.11—1
1390.167.72.12/3290.167.72.12 to 90.167.72.12—1
1490.167.72.13/3290.167.72.13 to 90.167.72.13—1
1590.167.72.14/3290.167.72.14 to 90.167.72.14—1
1690.167.72.15/3290.167.72.15 to 90.167.72.15—1
1790.167.72.16/3290.167.72.16 to 90.167.72.16—1
1890.167.72.17/3290.167.72.17 to 90.167.72.17—1
1990.167.72.18/3290.167.72.18 to 90.167.72.18—1
2090.167.72.19/3290.167.72.19 to 90.167.72.19—1
2190.167.72.20/3290.167.72.20 to 90.167.72.20—1
2290.167.72.21/3290.167.72.21 to 90.167.72.21—1
2390.167.72.22/3290.167.72.22 to 90.167.72.22—1
2490.167.72.23/3290.167.72.23 to 90.167.72.23—1
2590.167.72.24/3290.167.72.24 to 90.167.72.24—1
2690.167.72.25/3290.167.72.25 to 90.167.72.25—1
2790.167.72.26/3290.167.72.26 to 90.167.72.26—1
2890.167.72.27/3290.167.72.27 to 90.167.72.27—1
2990.167.72.28/3290.167.72.28 to 90.167.72.28—1
3090.167.72.29/3290.167.72.29 to 90.167.72.29—1
3190.167.72.30/3290.167.72.30 to 90.167.72.30—1
3290.167.72.31/3290.167.72.31 to 90.167.72.31—1
3390.167.72.32/3290.167.72.32 to 90.167.72.32—1
3490.167.72.33/3290.167.72.33 to 90.167.72.33—1
3590.167.72.34/3290.167.72.34 to 90.167.72.34—1
3690.167.72.35/3290.167.72.35 to 90.167.72.35—1
3790.167.72.36/3290.167.72.36 to 90.167.72.36—1
3890.167.72.37/3290.167.72.37 to 90.167.72.37—1
3990.167.72.38/3290.167.72.38 to 90.167.72.38—1
4090.167.72.39/3290.167.72.39 to 90.167.72.39—1
4190.167.72.40/3290.167.72.40 to 90.167.72.40—1
4290.167.72.41/3290.167.72.41 to 90.167.72.41—1
4390.167.72.42/3290.167.72.42 to 90.167.72.42—1
4490.167.72.43/3290.167.72.43 to 90.167.72.43—1
4590.167.72.44/3290.167.72.44 to 90.167.72.44—1
4690.167.72.45/3290.167.72.45 to 90.167.72.45—1
4790.167.72.46/3290.167.72.46 to 90.167.72.46—1
4890.167.72.47/3290.167.72.47 to 90.167.72.47—1
4990.167.72.48/3290.167.72.48 to 90.167.72.48—1
5090.167.72.49/3290.167.72.49 to 90.167.72.49—1
5190.167.72.50/3290.167.72.50 to 90.167.72.50—1
5290.167.72.51/3290.167.72.51 to 90.167.72.51—1
5390.167.72.52/3290.167.72.52 to 90.167.72.52—1
5490.167.72.53/3290.167.72.53 to 90.167.72.53—1
5590.167.72.54/3290.167.72.54 to 90.167.72.54—1
5690.167.72.55/3290.167.72.55 to 90.167.72.55—1
5790.167.72.56/3290.167.72.56 to 90.167.72.56—1
5890.167.72.57/3290.167.72.57 to 90.167.72.57—1
5990.167.72.58/3290.167.72.58 to 90.167.72.58—1
6090.167.72.59/3290.167.72.59 to 90.167.72.59—1
6190.167.72.60/3290.167.72.60 to 90.167.72.60—1
6290.167.72.61/3290.167.72.61 to 90.167.72.61—1
6390.167.72.62/3290.167.72.62 to 90.167.72.62—1
6490.167.72.63/3290.167.72.63 to 90.167.72.63—1
6590.167.72.64/3290.167.72.64 to 90.167.72.64—1
6690.167.72.65/3290.167.72.65 to 90.167.72.65—1
6790.167.72.66/3290.167.72.66 to 90.167.72.66—1
6890.167.72.67/3290.167.72.67 to 90.167.72.67—1
6990.167.72.68/3290.167.72.68 to 90.167.72.68—1
7090.167.72.69/3290.167.72.69 to 90.167.72.69—1
7190.167.72.70/3290.167.72.70 to 90.167.72.70—1
7290.167.72.71/3290.167.72.71 to 90.167.72.71—1
7390.167.72.72/3290.167.72.72 to 90.167.72.72—1
7490.167.72.73/3290.167.72.73 to 90.167.72.73—1
7590.167.72.74/3290.167.72.74 to 90.167.72.74—1
7690.167.72.75/3290.167.72.75 to 90.167.72.75—1
7790.167.72.76/3290.167.72.76 to 90.167.72.76—1
7890.167.72.77/3290.167.72.77 to 90.167.72.77—1
7990.167.72.78/3290.167.72.78 to 90.167.72.78—1
8090.167.72.79/3290.167.72.79 to 90.167.72.79—1
8190.167.72.80/3290.167.72.80 to 90.167.72.80—1
8290.167.72.81/3290.167.72.81 to 90.167.72.81—1
8390.167.72.82/3290.167.72.82 to 90.167.72.82—1
8490.167.72.83/3290.167.72.83 to 90.167.72.83—1
8590.167.72.84/3290.167.72.84 to 90.167.72.84—1
8690.167.72.85/3290.167.72.85 to 90.167.72.85—1
8790.167.72.86/3290.167.72.86 to 90.167.72.86—1
8890.167.72.87/3290.167.72.87 to 90.167.72.87—1
8990.167.72.88/3290.167.72.88 to 90.167.72.88—1
9090.167.72.89/3290.167.72.89 to 90.167.72.89—1
9190.167.72.90/3290.167.72.90 to 90.167.72.90—1
9290.167.72.91/3290.167.72.91 to 90.167.72.91—1
9390.167.72.92/3290.167.72.92 to 90.167.72.92—1
9490.167.72.93/3290.167.72.93 to 90.167.72.93—1
9590.167.72.94/3290.167.72.94 to 90.167.72.94—1
9690.167.72.95/3290.167.72.95 to 90.167.72.95—1
9790.167.72.96/3290.167.72.96 to 90.167.72.96—1
9890.167.72.97/3290.167.72.97 to 90.167.72.97—1
9990.167.72.98/3290.167.72.98 to 90.167.72.98—1
10090.167.72.99/3290.167.72.99 to 90.167.72.99—1
10190.167.72.100/3290.167.72.100 to 90.167.72.100—1
10290.167.72.101/3290.167.72.101 to 90.167.72.101—1
10390.167.72.102/3290.167.72.102 to 90.167.72.102—1
10490.167.72.103/3290.167.72.103 to 90.167.72.103—1
10590.167.72.104/3290.167.72.104 to 90.167.72.104—1
10690.167.72.105/3290.167.72.105 to 90.167.72.105—1
10790.167.72.106/3290.167.72.106 to 90.167.72.106—1
10890.167.72.107/3290.167.72.107 to 90.167.72.107—1
10990.167.72.108/3290.167.72.108 to 90.167.72.108—1
11090.167.72.109/3290.167.72.109 to 90.167.72.109—1
11190.167.72.110/3290.167.72.110 to 90.167.72.110—1
11290.167.72.111/3290.167.72.111 to 90.167.72.111—1
11390.167.72.112/3290.167.72.112 to 90.167.72.112—1
11490.167.72.113/3290.167.72.113 to 90.167.72.113—1
11590.167.72.114/3290.167.72.114 to 90.167.72.114—1
11690.167.72.115/3290.167.72.115 to 90.167.72.115—1
11790.167.72.116/3290.167.72.116 to 90.167.72.116—1
11890.167.72.117/3290.167.72.117 to 90.167.72.117—1
11990.167.72.118/3290.167.72.118 to 90.167.72.118—1
12090.167.72.119/3290.167.72.119 to 90.167.72.119—1
12190.167.72.120/3290.167.72.120 to 90.167.72.120—1
12290.167.72.121/3290.167.72.121 to 90.167.72.121—1
12390.167.72.122/3290.167.72.122 to 90.167.72.122—1
12490.167.72.123/3290.167.72.123 to 90.167.72.123—1
12590.167.72.124/3290.167.72.124 to 90.167.72.124—1
12690.167.72.125/3290.167.72.125 to 90.167.72.125—1
12790.167.72.126/3290.167.72.126 to 90.167.72.126—1
12890.167.72.127/3290.167.72.127 to 90.167.72.127—1
12990.167.72.128/3290.167.72.128 to 90.167.72.128—1
13090.167.72.129/3290.167.72.129 to 90.167.72.129—1
13190.167.72.130/3290.167.72.130 to 90.167.72.130—1
13290.167.72.131/3290.167.72.131 to 90.167.72.131—1
13390.167.72.132/3290.167.72.132 to 90.167.72.132—1
13490.167.72.133/3290.167.72.133 to 90.167.72.133—1
13590.167.72.134/3290.167.72.134 to 90.167.72.134—1
13690.167.72.135/3290.167.72.135 to 90.167.72.135—1
13790.167.72.136/3290.167.72.136 to 90.167.72.136—1
13890.167.72.137/3290.167.72.137 to 90.167.72.137—1
13990.167.72.138/3290.167.72.138 to 90.167.72.138—1
14090.167.72.139/3290.167.72.139 to 90.167.72.139—1
14190.167.72.140/3290.167.72.140 to 90.167.72.140—1
14290.167.72.141/3290.167.72.141 to 90.167.72.141—1
14390.167.72.142/3290.167.72.142 to 90.167.72.142—1
14490.167.72.143/3290.167.72.143 to 90.167.72.143—1
14590.167.72.144/3290.167.72.144 to 90.167.72.144—1
14690.167.72.145/3290.167.72.145 to 90.167.72.145—1
14790.167.72.146/3290.167.72.146 to 90.167.72.146—1
14890.167.72.147/3290.167.72.147 to 90.167.72.147—1
14990.167.72.148/3290.167.72.148 to 90.167.72.148—1
15090.167.72.149/3290.167.72.149 to 90.167.72.149—1
15190.167.72.150/3290.167.72.150 to 90.167.72.150—1
15290.167.72.151/3290.167.72.151 to 90.167.72.151—1
15390.167.72.152/3290.167.72.152 to 90.167.72.152—1
15490.167.72.153/3290.167.72.153 to 90.167.72.153—1
15590.167.72.154/3290.167.72.154 to 90.167.72.154—1
15690.167.72.155/3290.167.72.155 to 90.167.72.155—1
15790.167.72.156/3290.167.72.156 to 90.167.72.156—1
15890.167.72.157/3290.167.72.157 to 90.167.72.157—1
15990.167.72.158/3290.167.72.158 to 90.167.72.158—1
16090.167.72.159/3290.167.72.159 to 90.167.72.159—1
16190.167.72.160/3290.167.72.160 to 90.167.72.160—1
16290.167.72.161/3290.167.72.161 to 90.167.72.161—1
16390.167.72.162/3290.167.72.162 to 90.167.72.162—1
16490.167.72.163/3290.167.72.163 to 90.167.72.163—1
16590.167.72.164/3290.167.72.164 to 90.167.72.164—1
16690.167.72.165/3290.167.72.165 to 90.167.72.165—1
16790.167.72.166/3290.167.72.166 to 90.167.72.166—1
16890.167.72.167/3290.167.72.167 to 90.167.72.167—1
16990.167.72.168/3290.167.72.168 to 90.167.72.168—1
17090.167.72.169/3290.167.72.169 to 90.167.72.169—1
17190.167.72.170/3290.167.72.170 to 90.167.72.170—1
17290.167.72.171/3290.167.72.171 to 90.167.72.171—1
17390.167.72.172/3290.167.72.172 to 90.167.72.172—1
17490.167.72.173/3290.167.72.173 to 90.167.72.173—1
17590.167.72.174/3290.167.72.174 to 90.167.72.174—1
17690.167.72.175/3290.167.72.175 to 90.167.72.175—1
17790.167.72.176/3290.167.72.176 to 90.167.72.176—1
17890.167.72.177/3290.167.72.177 to 90.167.72.177—1
17990.167.72.178/3290.167.72.178 to 90.167.72.178—1
18090.167.72.179/3290.167.72.179 to 90.167.72.179—1
18190.167.72.180/3290.167.72.180 to 90.167.72.180—1
18290.167.72.181/3290.167.72.181 to 90.167.72.181—1
18390.167.72.182/3290.167.72.182 to 90.167.72.182—1
18490.167.72.183/3290.167.72.183 to 90.167.72.183—1
18590.167.72.184/3290.167.72.184 to 90.167.72.184—1
18690.167.72.185/3290.167.72.185 to 90.167.72.185—1
18790.167.72.186/3290.167.72.186 to 90.167.72.186—1
18890.167.72.187/3290.167.72.187 to 90.167.72.187—1
18990.167.72.188/3290.167.72.188 to 90.167.72.188—1
19090.167.72.189/3290.167.72.189 to 90.167.72.189—1
19190.167.72.190/3290.167.72.190 to 90.167.72.190—1
19290.167.72.191/3290.167.72.191 to 90.167.72.191—1
19390.167.72.192/3290.167.72.192 to 90.167.72.192—1
19490.167.72.193/3290.167.72.193 to 90.167.72.193—1
19590.167.72.194/3290.167.72.194 to 90.167.72.194—1
19690.167.72.195/3290.167.72.195 to 90.167.72.195—1
19790.167.72.196/3290.167.72.196 to 90.167.72.196—1
19890.167.72.197/3290.167.72.197 to 90.167.72.197—1
19990.167.72.198/3290.167.72.198 to 90.167.72.198—1
20090.167.72.199/3290.167.72.199 to 90.167.72.199—1
20190.167.72.200/3290.167.72.200 to 90.167.72.200—1
20290.167.72.201/3290.167.72.201 to 90.167.72.201—1
20390.167.72.202/3290.167.72.202 to 90.167.72.202—1
20490.167.72.203/3290.167.72.203 to 90.167.72.203—1
20590.167.72.204/3290.167.72.204 to 90.167.72.204—1
20690.167.72.205/3290.167.72.205 to 90.167.72.205—1
20790.167.72.206/3290.167.72.206 to 90.167.72.206—1
20890.167.72.207/3290.167.72.207 to 90.167.72.207—1
20990.167.72.208/3290.167.72.208 to 90.167.72.208—1
21090.167.72.209/3290.167.72.209 to 90.167.72.209—1
21190.167.72.210/3290.167.72.210 to 90.167.72.210—1
21290.167.72.211/3290.167.72.211 to 90.167.72.211—1
21390.167.72.212/3290.167.72.212 to 90.167.72.212—1
21490.167.72.213/3290.167.72.213 to 90.167.72.213—1
21590.167.72.214/3290.167.72.214 to 90.167.72.214—1
21690.167.72.215/3290.167.72.215 to 90.167.72.215—1
21790.167.72.216/3290.167.72.216 to 90.167.72.216—1
21890.167.72.217/3290.167.72.217 to 90.167.72.217—1
21990.167.72.218/3290.167.72.218 to 90.167.72.218—1
22090.167.72.219/3290.167.72.219 to 90.167.72.219—1
22190.167.72.220/3290.167.72.220 to 90.167.72.220—1
22290.167.72.221/3290.167.72.221 to 90.167.72.221—1
22390.167.72.222/3290.167.72.222 to 90.167.72.222—1
22490.167.72.223/3290.167.72.223 to 90.167.72.223—1
22590.167.72.224/3290.167.72.224 to 90.167.72.224—1
22690.167.72.225/3290.167.72.225 to 90.167.72.225—1
22790.167.72.226/3290.167.72.226 to 90.167.72.226—1
22890.167.72.227/3290.167.72.227 to 90.167.72.227—1
22990.167.72.228/3290.167.72.228 to 90.167.72.228—1
23090.167.72.229/3290.167.72.229 to 90.167.72.229—1
23190.167.72.230/3290.167.72.230 to 90.167.72.230—1
23290.167.72.231/3290.167.72.231 to 90.167.72.231—1
23390.167.72.232/3290.167.72.232 to 90.167.72.232—1
23490.167.72.233/3290.167.72.233 to 90.167.72.233—1
23590.167.72.234/3290.167.72.234 to 90.167.72.234—1
23690.167.72.235/3290.167.72.235 to 90.167.72.235—1
23790.167.72.236/3290.167.72.236 to 90.167.72.236—1
23890.167.72.237/3290.167.72.237 to 90.167.72.237—1
23990.167.72.238/3290.167.72.238 to 90.167.72.238—1
24090.167.72.239/3290.167.72.239 to 90.167.72.239—1
24190.167.72.240/3290.167.72.240 to 90.167.72.240—1
24290.167.72.241/3290.167.72.241 to 90.167.72.241—1
24390.167.72.242/3290.167.72.242 to 90.167.72.242—1
24490.167.72.243/3290.167.72.243 to 90.167.72.243—1
24590.167.72.244/3290.167.72.244 to 90.167.72.244—1
24690.167.72.245/3290.167.72.245 to 90.167.72.245—1
24790.167.72.246/3290.167.72.246 to 90.167.72.246—1
24890.167.72.247/3290.167.72.247 to 90.167.72.247—1
24990.167.72.248/3290.167.72.248 to 90.167.72.248—1
25090.167.72.249/3290.167.72.249 to 90.167.72.249—1
25190.167.72.250/3290.167.72.250 to 90.167.72.250—1
25290.167.72.251/3290.167.72.251 to 90.167.72.251—1
25390.167.72.252/3290.167.72.252 to 90.167.72.252—1
25490.167.72.253/3290.167.72.253 to 90.167.72.253—1
25590.167.72.254/3290.167.72.254 to 90.167.72.254—1
25690.167.72.255/3290.167.72.255 to 90.167.72.255—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.