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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.

Network71.2.76.0/24
Usable hosts254
Subnet mask255.255.255.0
Addresses256
Network address
71.2.76.0
Broadcast address
71.2.76.255
First usable
71.2.76.1
Last usable
71.2.76.254
Usable hosts
254 (256 less the network and broadcast addresses)
Subnet mask
255.255.255.0
Wildcard mask
0.0.0.255 (Cisco ACLs, OSPF)
Prefix length
/24
Type
Public public
Old class
A (default /8)
As numbers
Hex 47024C00 · Integer 1191332864 to 1191333119
Reverse DNS zone
76.2.71.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01000111.00000010.01001100..0000000071.2.76.0
Subnet mask11111111.11111111.11111111..00000000255.255.255.0
Network01000111.00000010.01001100..0000000071.2.76.0
Broadcast01000111.00000010.01001100..1111111171.2.76.255
Split into smaller subnets/32
/25 (2)/26 (4)/27 (8)/28 (16)/29 (32)/30 (64)/31 (128)/32 (256)

71.2.76.0/24 makes 256 subnets of /32.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
171.2.76.0/3271.2.76.0 to 71.2.76.0—1
271.2.76.1/3271.2.76.1 to 71.2.76.1—1
371.2.76.2/3271.2.76.2 to 71.2.76.2—1
471.2.76.3/3271.2.76.3 to 71.2.76.3—1
571.2.76.4/3271.2.76.4 to 71.2.76.4—1
671.2.76.5/3271.2.76.5 to 71.2.76.5—1
771.2.76.6/3271.2.76.6 to 71.2.76.6—1
871.2.76.7/3271.2.76.7 to 71.2.76.7—1
971.2.76.8/3271.2.76.8 to 71.2.76.8—1
1071.2.76.9/3271.2.76.9 to 71.2.76.9—1
1171.2.76.10/3271.2.76.10 to 71.2.76.10—1
1271.2.76.11/3271.2.76.11 to 71.2.76.11—1
1371.2.76.12/3271.2.76.12 to 71.2.76.12—1
1471.2.76.13/3271.2.76.13 to 71.2.76.13—1
1571.2.76.14/3271.2.76.14 to 71.2.76.14—1
1671.2.76.15/3271.2.76.15 to 71.2.76.15—1
1771.2.76.16/3271.2.76.16 to 71.2.76.16—1
1871.2.76.17/3271.2.76.17 to 71.2.76.17—1
1971.2.76.18/3271.2.76.18 to 71.2.76.18—1
2071.2.76.19/3271.2.76.19 to 71.2.76.19—1
2171.2.76.20/3271.2.76.20 to 71.2.76.20—1
2271.2.76.21/3271.2.76.21 to 71.2.76.21—1
2371.2.76.22/3271.2.76.22 to 71.2.76.22—1
2471.2.76.23/3271.2.76.23 to 71.2.76.23—1
2571.2.76.24/3271.2.76.24 to 71.2.76.24—1
2671.2.76.25/3271.2.76.25 to 71.2.76.25—1
2771.2.76.26/3271.2.76.26 to 71.2.76.26—1
2871.2.76.27/3271.2.76.27 to 71.2.76.27—1
2971.2.76.28/3271.2.76.28 to 71.2.76.28—1
3071.2.76.29/3271.2.76.29 to 71.2.76.29—1
3171.2.76.30/3271.2.76.30 to 71.2.76.30—1
3271.2.76.31/3271.2.76.31 to 71.2.76.31—1
3371.2.76.32/3271.2.76.32 to 71.2.76.32—1
3471.2.76.33/3271.2.76.33 to 71.2.76.33—1
3571.2.76.34/3271.2.76.34 to 71.2.76.34—1
3671.2.76.35/3271.2.76.35 to 71.2.76.35—1
3771.2.76.36/3271.2.76.36 to 71.2.76.36—1
3871.2.76.37/3271.2.76.37 to 71.2.76.37—1
3971.2.76.38/3271.2.76.38 to 71.2.76.38—1
4071.2.76.39/3271.2.76.39 to 71.2.76.39—1
4171.2.76.40/3271.2.76.40 to 71.2.76.40—1
4271.2.76.41/3271.2.76.41 to 71.2.76.41—1
4371.2.76.42/3271.2.76.42 to 71.2.76.42—1
4471.2.76.43/3271.2.76.43 to 71.2.76.43—1
4571.2.76.44/3271.2.76.44 to 71.2.76.44—1
4671.2.76.45/3271.2.76.45 to 71.2.76.45—1
4771.2.76.46/3271.2.76.46 to 71.2.76.46—1
4871.2.76.47/3271.2.76.47 to 71.2.76.47—1
4971.2.76.48/3271.2.76.48 to 71.2.76.48—1
5071.2.76.49/3271.2.76.49 to 71.2.76.49—1
5171.2.76.50/3271.2.76.50 to 71.2.76.50—1
5271.2.76.51/3271.2.76.51 to 71.2.76.51—1
5371.2.76.52/3271.2.76.52 to 71.2.76.52—1
5471.2.76.53/3271.2.76.53 to 71.2.76.53—1
5571.2.76.54/3271.2.76.54 to 71.2.76.54—1
5671.2.76.55/3271.2.76.55 to 71.2.76.55—1
5771.2.76.56/3271.2.76.56 to 71.2.76.56—1
5871.2.76.57/3271.2.76.57 to 71.2.76.57—1
5971.2.76.58/3271.2.76.58 to 71.2.76.58—1
6071.2.76.59/3271.2.76.59 to 71.2.76.59—1
6171.2.76.60/3271.2.76.60 to 71.2.76.60—1
6271.2.76.61/3271.2.76.61 to 71.2.76.61—1
6371.2.76.62/3271.2.76.62 to 71.2.76.62—1
6471.2.76.63/3271.2.76.63 to 71.2.76.63—1
6571.2.76.64/3271.2.76.64 to 71.2.76.64—1
6671.2.76.65/3271.2.76.65 to 71.2.76.65—1
6771.2.76.66/3271.2.76.66 to 71.2.76.66—1
6871.2.76.67/3271.2.76.67 to 71.2.76.67—1
6971.2.76.68/3271.2.76.68 to 71.2.76.68—1
7071.2.76.69/3271.2.76.69 to 71.2.76.69—1
7171.2.76.70/3271.2.76.70 to 71.2.76.70—1
7271.2.76.71/3271.2.76.71 to 71.2.76.71—1
7371.2.76.72/3271.2.76.72 to 71.2.76.72—1
7471.2.76.73/3271.2.76.73 to 71.2.76.73—1
7571.2.76.74/3271.2.76.74 to 71.2.76.74—1
7671.2.76.75/3271.2.76.75 to 71.2.76.75—1
7771.2.76.76/3271.2.76.76 to 71.2.76.76—1
7871.2.76.77/3271.2.76.77 to 71.2.76.77—1
7971.2.76.78/3271.2.76.78 to 71.2.76.78—1
8071.2.76.79/3271.2.76.79 to 71.2.76.79—1
8171.2.76.80/3271.2.76.80 to 71.2.76.80—1
8271.2.76.81/3271.2.76.81 to 71.2.76.81—1
8371.2.76.82/3271.2.76.82 to 71.2.76.82—1
8471.2.76.83/3271.2.76.83 to 71.2.76.83—1
8571.2.76.84/3271.2.76.84 to 71.2.76.84—1
8671.2.76.85/3271.2.76.85 to 71.2.76.85—1
8771.2.76.86/3271.2.76.86 to 71.2.76.86—1
8871.2.76.87/3271.2.76.87 to 71.2.76.87—1
8971.2.76.88/3271.2.76.88 to 71.2.76.88—1
9071.2.76.89/3271.2.76.89 to 71.2.76.89—1
9171.2.76.90/3271.2.76.90 to 71.2.76.90—1
9271.2.76.91/3271.2.76.91 to 71.2.76.91—1
9371.2.76.92/3271.2.76.92 to 71.2.76.92—1
9471.2.76.93/3271.2.76.93 to 71.2.76.93—1
9571.2.76.94/3271.2.76.94 to 71.2.76.94—1
9671.2.76.95/3271.2.76.95 to 71.2.76.95—1
9771.2.76.96/3271.2.76.96 to 71.2.76.96—1
9871.2.76.97/3271.2.76.97 to 71.2.76.97—1
9971.2.76.98/3271.2.76.98 to 71.2.76.98—1
10071.2.76.99/3271.2.76.99 to 71.2.76.99—1
10171.2.76.100/3271.2.76.100 to 71.2.76.100—1
10271.2.76.101/3271.2.76.101 to 71.2.76.101—1
10371.2.76.102/3271.2.76.102 to 71.2.76.102—1
10471.2.76.103/3271.2.76.103 to 71.2.76.103—1
10571.2.76.104/3271.2.76.104 to 71.2.76.104—1
10671.2.76.105/3271.2.76.105 to 71.2.76.105—1
10771.2.76.106/3271.2.76.106 to 71.2.76.106—1
10871.2.76.107/3271.2.76.107 to 71.2.76.107—1
10971.2.76.108/3271.2.76.108 to 71.2.76.108—1
11071.2.76.109/3271.2.76.109 to 71.2.76.109—1
11171.2.76.110/3271.2.76.110 to 71.2.76.110—1
11271.2.76.111/3271.2.76.111 to 71.2.76.111—1
11371.2.76.112/3271.2.76.112 to 71.2.76.112—1
11471.2.76.113/3271.2.76.113 to 71.2.76.113—1
11571.2.76.114/3271.2.76.114 to 71.2.76.114—1
11671.2.76.115/3271.2.76.115 to 71.2.76.115—1
11771.2.76.116/3271.2.76.116 to 71.2.76.116—1
11871.2.76.117/3271.2.76.117 to 71.2.76.117—1
11971.2.76.118/3271.2.76.118 to 71.2.76.118—1
12071.2.76.119/3271.2.76.119 to 71.2.76.119—1
12171.2.76.120/3271.2.76.120 to 71.2.76.120—1
12271.2.76.121/3271.2.76.121 to 71.2.76.121—1
12371.2.76.122/3271.2.76.122 to 71.2.76.122—1
12471.2.76.123/3271.2.76.123 to 71.2.76.123—1
12571.2.76.124/3271.2.76.124 to 71.2.76.124—1
12671.2.76.125/3271.2.76.125 to 71.2.76.125—1
12771.2.76.126/3271.2.76.126 to 71.2.76.126—1
12871.2.76.127/3271.2.76.127 to 71.2.76.127—1
12971.2.76.128/3271.2.76.128 to 71.2.76.128—1
13071.2.76.129/3271.2.76.129 to 71.2.76.129—1
13171.2.76.130/3271.2.76.130 to 71.2.76.130—1
13271.2.76.131/3271.2.76.131 to 71.2.76.131—1
13371.2.76.132/3271.2.76.132 to 71.2.76.132—1
13471.2.76.133/3271.2.76.133 to 71.2.76.133—1
13571.2.76.134/3271.2.76.134 to 71.2.76.134—1
13671.2.76.135/3271.2.76.135 to 71.2.76.135—1
13771.2.76.136/3271.2.76.136 to 71.2.76.136—1
13871.2.76.137/3271.2.76.137 to 71.2.76.137—1
13971.2.76.138/3271.2.76.138 to 71.2.76.138—1
14071.2.76.139/3271.2.76.139 to 71.2.76.139—1
14171.2.76.140/3271.2.76.140 to 71.2.76.140—1
14271.2.76.141/3271.2.76.141 to 71.2.76.141—1
14371.2.76.142/3271.2.76.142 to 71.2.76.142—1
14471.2.76.143/3271.2.76.143 to 71.2.76.143—1
14571.2.76.144/3271.2.76.144 to 71.2.76.144—1
14671.2.76.145/3271.2.76.145 to 71.2.76.145—1
14771.2.76.146/3271.2.76.146 to 71.2.76.146—1
14871.2.76.147/3271.2.76.147 to 71.2.76.147—1
14971.2.76.148/3271.2.76.148 to 71.2.76.148—1
15071.2.76.149/3271.2.76.149 to 71.2.76.149—1
15171.2.76.150/3271.2.76.150 to 71.2.76.150—1
15271.2.76.151/3271.2.76.151 to 71.2.76.151—1
15371.2.76.152/3271.2.76.152 to 71.2.76.152—1
15471.2.76.153/3271.2.76.153 to 71.2.76.153—1
15571.2.76.154/3271.2.76.154 to 71.2.76.154—1
15671.2.76.155/3271.2.76.155 to 71.2.76.155—1
15771.2.76.156/3271.2.76.156 to 71.2.76.156—1
15871.2.76.157/3271.2.76.157 to 71.2.76.157—1
15971.2.76.158/3271.2.76.158 to 71.2.76.158—1
16071.2.76.159/3271.2.76.159 to 71.2.76.159—1
16171.2.76.160/3271.2.76.160 to 71.2.76.160—1
16271.2.76.161/3271.2.76.161 to 71.2.76.161—1
16371.2.76.162/3271.2.76.162 to 71.2.76.162—1
16471.2.76.163/3271.2.76.163 to 71.2.76.163—1
16571.2.76.164/3271.2.76.164 to 71.2.76.164—1
16671.2.76.165/3271.2.76.165 to 71.2.76.165—1
16771.2.76.166/3271.2.76.166 to 71.2.76.166—1
16871.2.76.167/3271.2.76.167 to 71.2.76.167—1
16971.2.76.168/3271.2.76.168 to 71.2.76.168—1
17071.2.76.169/3271.2.76.169 to 71.2.76.169—1
17171.2.76.170/3271.2.76.170 to 71.2.76.170—1
17271.2.76.171/3271.2.76.171 to 71.2.76.171—1
17371.2.76.172/3271.2.76.172 to 71.2.76.172—1
17471.2.76.173/3271.2.76.173 to 71.2.76.173—1
17571.2.76.174/3271.2.76.174 to 71.2.76.174—1
17671.2.76.175/3271.2.76.175 to 71.2.76.175—1
17771.2.76.176/3271.2.76.176 to 71.2.76.176—1
17871.2.76.177/3271.2.76.177 to 71.2.76.177—1
17971.2.76.178/3271.2.76.178 to 71.2.76.178—1
18071.2.76.179/3271.2.76.179 to 71.2.76.179—1
18171.2.76.180/3271.2.76.180 to 71.2.76.180—1
18271.2.76.181/3271.2.76.181 to 71.2.76.181—1
18371.2.76.182/3271.2.76.182 to 71.2.76.182—1
18471.2.76.183/3271.2.76.183 to 71.2.76.183—1
18571.2.76.184/3271.2.76.184 to 71.2.76.184—1
18671.2.76.185/3271.2.76.185 to 71.2.76.185—1
18771.2.76.186/3271.2.76.186 to 71.2.76.186—1
18871.2.76.187/3271.2.76.187 to 71.2.76.187—1
18971.2.76.188/3271.2.76.188 to 71.2.76.188—1
19071.2.76.189/3271.2.76.189 to 71.2.76.189—1
19171.2.76.190/3271.2.76.190 to 71.2.76.190—1
19271.2.76.191/3271.2.76.191 to 71.2.76.191—1
19371.2.76.192/3271.2.76.192 to 71.2.76.192—1
19471.2.76.193/3271.2.76.193 to 71.2.76.193—1
19571.2.76.194/3271.2.76.194 to 71.2.76.194—1
19671.2.76.195/3271.2.76.195 to 71.2.76.195—1
19771.2.76.196/3271.2.76.196 to 71.2.76.196—1
19871.2.76.197/3271.2.76.197 to 71.2.76.197—1
19971.2.76.198/3271.2.76.198 to 71.2.76.198—1
20071.2.76.199/3271.2.76.199 to 71.2.76.199—1
20171.2.76.200/3271.2.76.200 to 71.2.76.200—1
20271.2.76.201/3271.2.76.201 to 71.2.76.201—1
20371.2.76.202/3271.2.76.202 to 71.2.76.202—1
20471.2.76.203/3271.2.76.203 to 71.2.76.203—1
20571.2.76.204/3271.2.76.204 to 71.2.76.204—1
20671.2.76.205/3271.2.76.205 to 71.2.76.205—1
20771.2.76.206/3271.2.76.206 to 71.2.76.206—1
20871.2.76.207/3271.2.76.207 to 71.2.76.207—1
20971.2.76.208/3271.2.76.208 to 71.2.76.208—1
21071.2.76.209/3271.2.76.209 to 71.2.76.209—1
21171.2.76.210/3271.2.76.210 to 71.2.76.210—1
21271.2.76.211/3271.2.76.211 to 71.2.76.211—1
21371.2.76.212/3271.2.76.212 to 71.2.76.212—1
21471.2.76.213/3271.2.76.213 to 71.2.76.213—1
21571.2.76.214/3271.2.76.214 to 71.2.76.214—1
21671.2.76.215/3271.2.76.215 to 71.2.76.215—1
21771.2.76.216/3271.2.76.216 to 71.2.76.216—1
21871.2.76.217/3271.2.76.217 to 71.2.76.217—1
21971.2.76.218/3271.2.76.218 to 71.2.76.218—1
22071.2.76.219/3271.2.76.219 to 71.2.76.219—1
22171.2.76.220/3271.2.76.220 to 71.2.76.220—1
22271.2.76.221/3271.2.76.221 to 71.2.76.221—1
22371.2.76.222/3271.2.76.222 to 71.2.76.222—1
22471.2.76.223/3271.2.76.223 to 71.2.76.223—1
22571.2.76.224/3271.2.76.224 to 71.2.76.224—1
22671.2.76.225/3271.2.76.225 to 71.2.76.225—1
22771.2.76.226/3271.2.76.226 to 71.2.76.226—1
22871.2.76.227/3271.2.76.227 to 71.2.76.227—1
22971.2.76.228/3271.2.76.228 to 71.2.76.228—1
23071.2.76.229/3271.2.76.229 to 71.2.76.229—1
23171.2.76.230/3271.2.76.230 to 71.2.76.230—1
23271.2.76.231/3271.2.76.231 to 71.2.76.231—1
23371.2.76.232/3271.2.76.232 to 71.2.76.232—1
23471.2.76.233/3271.2.76.233 to 71.2.76.233—1
23571.2.76.234/3271.2.76.234 to 71.2.76.234—1
23671.2.76.235/3271.2.76.235 to 71.2.76.235—1
23771.2.76.236/3271.2.76.236 to 71.2.76.236—1
23871.2.76.237/3271.2.76.237 to 71.2.76.237—1
23971.2.76.238/3271.2.76.238 to 71.2.76.238—1
24071.2.76.239/3271.2.76.239 to 71.2.76.239—1
24171.2.76.240/3271.2.76.240 to 71.2.76.240—1
24271.2.76.241/3271.2.76.241 to 71.2.76.241—1
24371.2.76.242/3271.2.76.242 to 71.2.76.242—1
24471.2.76.243/3271.2.76.243 to 71.2.76.243—1
24571.2.76.244/3271.2.76.244 to 71.2.76.244—1
24671.2.76.245/3271.2.76.245 to 71.2.76.245—1
24771.2.76.246/3271.2.76.246 to 71.2.76.246—1
24871.2.76.247/3271.2.76.247 to 71.2.76.247—1
24971.2.76.248/3271.2.76.248 to 71.2.76.248—1
25071.2.76.249/3271.2.76.249 to 71.2.76.249—1
25171.2.76.250/3271.2.76.250 to 71.2.76.250—1
25271.2.76.251/3271.2.76.251 to 71.2.76.251—1
25371.2.76.252/3271.2.76.252 to 71.2.76.252—1
25471.2.76.253/3271.2.76.253 to 71.2.76.253—1
25571.2.76.254/3271.2.76.254 to 71.2.76.254—1
25671.2.76.255/3271.2.76.255 to 71.2.76.255—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.