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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.

Network41.167.72.0/24
Usable hosts254
Subnet mask255.255.255.0
Addresses256
Network address
41.167.72.0
Broadcast address
41.167.72.255
First usable
41.167.72.1
Last usable
41.167.72.254
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 29A74800 · Integer 698828800 to 698829055
Reverse DNS zone
72.167.41.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101001.10100111.01001000..0000000041.167.72.0
Subnet mask11111111.11111111.11111111..00000000255.255.255.0
Network00101001.10100111.01001000..0000000041.167.72.0
Broadcast00101001.10100111.01001000..1111111141.167.72.255
Split into smaller subnets/32
/25 (2)/26 (4)/27 (8)/28 (16)/29 (32)/30 (64)/31 (128)/32 (256)

41.167.72.0/24 makes 256 subnets of /32.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
141.167.72.0/3241.167.72.0 to 41.167.72.0—1
241.167.72.1/3241.167.72.1 to 41.167.72.1—1
341.167.72.2/3241.167.72.2 to 41.167.72.2—1
441.167.72.3/3241.167.72.3 to 41.167.72.3—1
541.167.72.4/3241.167.72.4 to 41.167.72.4—1
641.167.72.5/3241.167.72.5 to 41.167.72.5—1
741.167.72.6/3241.167.72.6 to 41.167.72.6—1
841.167.72.7/3241.167.72.7 to 41.167.72.7—1
941.167.72.8/3241.167.72.8 to 41.167.72.8—1
1041.167.72.9/3241.167.72.9 to 41.167.72.9—1
1141.167.72.10/3241.167.72.10 to 41.167.72.10—1
1241.167.72.11/3241.167.72.11 to 41.167.72.11—1
1341.167.72.12/3241.167.72.12 to 41.167.72.12—1
1441.167.72.13/3241.167.72.13 to 41.167.72.13—1
1541.167.72.14/3241.167.72.14 to 41.167.72.14—1
1641.167.72.15/3241.167.72.15 to 41.167.72.15—1
1741.167.72.16/3241.167.72.16 to 41.167.72.16—1
1841.167.72.17/3241.167.72.17 to 41.167.72.17—1
1941.167.72.18/3241.167.72.18 to 41.167.72.18—1
2041.167.72.19/3241.167.72.19 to 41.167.72.19—1
2141.167.72.20/3241.167.72.20 to 41.167.72.20—1
2241.167.72.21/3241.167.72.21 to 41.167.72.21—1
2341.167.72.22/3241.167.72.22 to 41.167.72.22—1
2441.167.72.23/3241.167.72.23 to 41.167.72.23—1
2541.167.72.24/3241.167.72.24 to 41.167.72.24—1
2641.167.72.25/3241.167.72.25 to 41.167.72.25—1
2741.167.72.26/3241.167.72.26 to 41.167.72.26—1
2841.167.72.27/3241.167.72.27 to 41.167.72.27—1
2941.167.72.28/3241.167.72.28 to 41.167.72.28—1
3041.167.72.29/3241.167.72.29 to 41.167.72.29—1
3141.167.72.30/3241.167.72.30 to 41.167.72.30—1
3241.167.72.31/3241.167.72.31 to 41.167.72.31—1
3341.167.72.32/3241.167.72.32 to 41.167.72.32—1
3441.167.72.33/3241.167.72.33 to 41.167.72.33—1
3541.167.72.34/3241.167.72.34 to 41.167.72.34—1
3641.167.72.35/3241.167.72.35 to 41.167.72.35—1
3741.167.72.36/3241.167.72.36 to 41.167.72.36—1
3841.167.72.37/3241.167.72.37 to 41.167.72.37—1
3941.167.72.38/3241.167.72.38 to 41.167.72.38—1
4041.167.72.39/3241.167.72.39 to 41.167.72.39—1
4141.167.72.40/3241.167.72.40 to 41.167.72.40—1
4241.167.72.41/3241.167.72.41 to 41.167.72.41—1
4341.167.72.42/3241.167.72.42 to 41.167.72.42—1
4441.167.72.43/3241.167.72.43 to 41.167.72.43—1
4541.167.72.44/3241.167.72.44 to 41.167.72.44—1
4641.167.72.45/3241.167.72.45 to 41.167.72.45—1
4741.167.72.46/3241.167.72.46 to 41.167.72.46—1
4841.167.72.47/3241.167.72.47 to 41.167.72.47—1
4941.167.72.48/3241.167.72.48 to 41.167.72.48—1
5041.167.72.49/3241.167.72.49 to 41.167.72.49—1
5141.167.72.50/3241.167.72.50 to 41.167.72.50—1
5241.167.72.51/3241.167.72.51 to 41.167.72.51—1
5341.167.72.52/3241.167.72.52 to 41.167.72.52—1
5441.167.72.53/3241.167.72.53 to 41.167.72.53—1
5541.167.72.54/3241.167.72.54 to 41.167.72.54—1
5641.167.72.55/3241.167.72.55 to 41.167.72.55—1
5741.167.72.56/3241.167.72.56 to 41.167.72.56—1
5841.167.72.57/3241.167.72.57 to 41.167.72.57—1
5941.167.72.58/3241.167.72.58 to 41.167.72.58—1
6041.167.72.59/3241.167.72.59 to 41.167.72.59—1
6141.167.72.60/3241.167.72.60 to 41.167.72.60—1
6241.167.72.61/3241.167.72.61 to 41.167.72.61—1
6341.167.72.62/3241.167.72.62 to 41.167.72.62—1
6441.167.72.63/3241.167.72.63 to 41.167.72.63—1
6541.167.72.64/3241.167.72.64 to 41.167.72.64—1
6641.167.72.65/3241.167.72.65 to 41.167.72.65—1
6741.167.72.66/3241.167.72.66 to 41.167.72.66—1
6841.167.72.67/3241.167.72.67 to 41.167.72.67—1
6941.167.72.68/3241.167.72.68 to 41.167.72.68—1
7041.167.72.69/3241.167.72.69 to 41.167.72.69—1
7141.167.72.70/3241.167.72.70 to 41.167.72.70—1
7241.167.72.71/3241.167.72.71 to 41.167.72.71—1
7341.167.72.72/3241.167.72.72 to 41.167.72.72—1
7441.167.72.73/3241.167.72.73 to 41.167.72.73—1
7541.167.72.74/3241.167.72.74 to 41.167.72.74—1
7641.167.72.75/3241.167.72.75 to 41.167.72.75—1
7741.167.72.76/3241.167.72.76 to 41.167.72.76—1
7841.167.72.77/3241.167.72.77 to 41.167.72.77—1
7941.167.72.78/3241.167.72.78 to 41.167.72.78—1
8041.167.72.79/3241.167.72.79 to 41.167.72.79—1
8141.167.72.80/3241.167.72.80 to 41.167.72.80—1
8241.167.72.81/3241.167.72.81 to 41.167.72.81—1
8341.167.72.82/3241.167.72.82 to 41.167.72.82—1
8441.167.72.83/3241.167.72.83 to 41.167.72.83—1
8541.167.72.84/3241.167.72.84 to 41.167.72.84—1
8641.167.72.85/3241.167.72.85 to 41.167.72.85—1
8741.167.72.86/3241.167.72.86 to 41.167.72.86—1
8841.167.72.87/3241.167.72.87 to 41.167.72.87—1
8941.167.72.88/3241.167.72.88 to 41.167.72.88—1
9041.167.72.89/3241.167.72.89 to 41.167.72.89—1
9141.167.72.90/3241.167.72.90 to 41.167.72.90—1
9241.167.72.91/3241.167.72.91 to 41.167.72.91—1
9341.167.72.92/3241.167.72.92 to 41.167.72.92—1
9441.167.72.93/3241.167.72.93 to 41.167.72.93—1
9541.167.72.94/3241.167.72.94 to 41.167.72.94—1
9641.167.72.95/3241.167.72.95 to 41.167.72.95—1
9741.167.72.96/3241.167.72.96 to 41.167.72.96—1
9841.167.72.97/3241.167.72.97 to 41.167.72.97—1
9941.167.72.98/3241.167.72.98 to 41.167.72.98—1
10041.167.72.99/3241.167.72.99 to 41.167.72.99—1
10141.167.72.100/3241.167.72.100 to 41.167.72.100—1
10241.167.72.101/3241.167.72.101 to 41.167.72.101—1
10341.167.72.102/3241.167.72.102 to 41.167.72.102—1
10441.167.72.103/3241.167.72.103 to 41.167.72.103—1
10541.167.72.104/3241.167.72.104 to 41.167.72.104—1
10641.167.72.105/3241.167.72.105 to 41.167.72.105—1
10741.167.72.106/3241.167.72.106 to 41.167.72.106—1
10841.167.72.107/3241.167.72.107 to 41.167.72.107—1
10941.167.72.108/3241.167.72.108 to 41.167.72.108—1
11041.167.72.109/3241.167.72.109 to 41.167.72.109—1
11141.167.72.110/3241.167.72.110 to 41.167.72.110—1
11241.167.72.111/3241.167.72.111 to 41.167.72.111—1
11341.167.72.112/3241.167.72.112 to 41.167.72.112—1
11441.167.72.113/3241.167.72.113 to 41.167.72.113—1
11541.167.72.114/3241.167.72.114 to 41.167.72.114—1
11641.167.72.115/3241.167.72.115 to 41.167.72.115—1
11741.167.72.116/3241.167.72.116 to 41.167.72.116—1
11841.167.72.117/3241.167.72.117 to 41.167.72.117—1
11941.167.72.118/3241.167.72.118 to 41.167.72.118—1
12041.167.72.119/3241.167.72.119 to 41.167.72.119—1
12141.167.72.120/3241.167.72.120 to 41.167.72.120—1
12241.167.72.121/3241.167.72.121 to 41.167.72.121—1
12341.167.72.122/3241.167.72.122 to 41.167.72.122—1
12441.167.72.123/3241.167.72.123 to 41.167.72.123—1
12541.167.72.124/3241.167.72.124 to 41.167.72.124—1
12641.167.72.125/3241.167.72.125 to 41.167.72.125—1
12741.167.72.126/3241.167.72.126 to 41.167.72.126—1
12841.167.72.127/3241.167.72.127 to 41.167.72.127—1
12941.167.72.128/3241.167.72.128 to 41.167.72.128—1
13041.167.72.129/3241.167.72.129 to 41.167.72.129—1
13141.167.72.130/3241.167.72.130 to 41.167.72.130—1
13241.167.72.131/3241.167.72.131 to 41.167.72.131—1
13341.167.72.132/3241.167.72.132 to 41.167.72.132—1
13441.167.72.133/3241.167.72.133 to 41.167.72.133—1
13541.167.72.134/3241.167.72.134 to 41.167.72.134—1
13641.167.72.135/3241.167.72.135 to 41.167.72.135—1
13741.167.72.136/3241.167.72.136 to 41.167.72.136—1
13841.167.72.137/3241.167.72.137 to 41.167.72.137—1
13941.167.72.138/3241.167.72.138 to 41.167.72.138—1
14041.167.72.139/3241.167.72.139 to 41.167.72.139—1
14141.167.72.140/3241.167.72.140 to 41.167.72.140—1
14241.167.72.141/3241.167.72.141 to 41.167.72.141—1
14341.167.72.142/3241.167.72.142 to 41.167.72.142—1
14441.167.72.143/3241.167.72.143 to 41.167.72.143—1
14541.167.72.144/3241.167.72.144 to 41.167.72.144—1
14641.167.72.145/3241.167.72.145 to 41.167.72.145—1
14741.167.72.146/3241.167.72.146 to 41.167.72.146—1
14841.167.72.147/3241.167.72.147 to 41.167.72.147—1
14941.167.72.148/3241.167.72.148 to 41.167.72.148—1
15041.167.72.149/3241.167.72.149 to 41.167.72.149—1
15141.167.72.150/3241.167.72.150 to 41.167.72.150—1
15241.167.72.151/3241.167.72.151 to 41.167.72.151—1
15341.167.72.152/3241.167.72.152 to 41.167.72.152—1
15441.167.72.153/3241.167.72.153 to 41.167.72.153—1
15541.167.72.154/3241.167.72.154 to 41.167.72.154—1
15641.167.72.155/3241.167.72.155 to 41.167.72.155—1
15741.167.72.156/3241.167.72.156 to 41.167.72.156—1
15841.167.72.157/3241.167.72.157 to 41.167.72.157—1
15941.167.72.158/3241.167.72.158 to 41.167.72.158—1
16041.167.72.159/3241.167.72.159 to 41.167.72.159—1
16141.167.72.160/3241.167.72.160 to 41.167.72.160—1
16241.167.72.161/3241.167.72.161 to 41.167.72.161—1
16341.167.72.162/3241.167.72.162 to 41.167.72.162—1
16441.167.72.163/3241.167.72.163 to 41.167.72.163—1
16541.167.72.164/3241.167.72.164 to 41.167.72.164—1
16641.167.72.165/3241.167.72.165 to 41.167.72.165—1
16741.167.72.166/3241.167.72.166 to 41.167.72.166—1
16841.167.72.167/3241.167.72.167 to 41.167.72.167—1
16941.167.72.168/3241.167.72.168 to 41.167.72.168—1
17041.167.72.169/3241.167.72.169 to 41.167.72.169—1
17141.167.72.170/3241.167.72.170 to 41.167.72.170—1
17241.167.72.171/3241.167.72.171 to 41.167.72.171—1
17341.167.72.172/3241.167.72.172 to 41.167.72.172—1
17441.167.72.173/3241.167.72.173 to 41.167.72.173—1
17541.167.72.174/3241.167.72.174 to 41.167.72.174—1
17641.167.72.175/3241.167.72.175 to 41.167.72.175—1
17741.167.72.176/3241.167.72.176 to 41.167.72.176—1
17841.167.72.177/3241.167.72.177 to 41.167.72.177—1
17941.167.72.178/3241.167.72.178 to 41.167.72.178—1
18041.167.72.179/3241.167.72.179 to 41.167.72.179—1
18141.167.72.180/3241.167.72.180 to 41.167.72.180—1
18241.167.72.181/3241.167.72.181 to 41.167.72.181—1
18341.167.72.182/3241.167.72.182 to 41.167.72.182—1
18441.167.72.183/3241.167.72.183 to 41.167.72.183—1
18541.167.72.184/3241.167.72.184 to 41.167.72.184—1
18641.167.72.185/3241.167.72.185 to 41.167.72.185—1
18741.167.72.186/3241.167.72.186 to 41.167.72.186—1
18841.167.72.187/3241.167.72.187 to 41.167.72.187—1
18941.167.72.188/3241.167.72.188 to 41.167.72.188—1
19041.167.72.189/3241.167.72.189 to 41.167.72.189—1
19141.167.72.190/3241.167.72.190 to 41.167.72.190—1
19241.167.72.191/3241.167.72.191 to 41.167.72.191—1
19341.167.72.192/3241.167.72.192 to 41.167.72.192—1
19441.167.72.193/3241.167.72.193 to 41.167.72.193—1
19541.167.72.194/3241.167.72.194 to 41.167.72.194—1
19641.167.72.195/3241.167.72.195 to 41.167.72.195—1
19741.167.72.196/3241.167.72.196 to 41.167.72.196—1
19841.167.72.197/3241.167.72.197 to 41.167.72.197—1
19941.167.72.198/3241.167.72.198 to 41.167.72.198—1
20041.167.72.199/3241.167.72.199 to 41.167.72.199—1
20141.167.72.200/3241.167.72.200 to 41.167.72.200—1
20241.167.72.201/3241.167.72.201 to 41.167.72.201—1
20341.167.72.202/3241.167.72.202 to 41.167.72.202—1
20441.167.72.203/3241.167.72.203 to 41.167.72.203—1
20541.167.72.204/3241.167.72.204 to 41.167.72.204—1
20641.167.72.205/3241.167.72.205 to 41.167.72.205—1
20741.167.72.206/3241.167.72.206 to 41.167.72.206—1
20841.167.72.207/3241.167.72.207 to 41.167.72.207—1
20941.167.72.208/3241.167.72.208 to 41.167.72.208—1
21041.167.72.209/3241.167.72.209 to 41.167.72.209—1
21141.167.72.210/3241.167.72.210 to 41.167.72.210—1
21241.167.72.211/3241.167.72.211 to 41.167.72.211—1
21341.167.72.212/3241.167.72.212 to 41.167.72.212—1
21441.167.72.213/3241.167.72.213 to 41.167.72.213—1
21541.167.72.214/3241.167.72.214 to 41.167.72.214—1
21641.167.72.215/3241.167.72.215 to 41.167.72.215—1
21741.167.72.216/3241.167.72.216 to 41.167.72.216—1
21841.167.72.217/3241.167.72.217 to 41.167.72.217—1
21941.167.72.218/3241.167.72.218 to 41.167.72.218—1
22041.167.72.219/3241.167.72.219 to 41.167.72.219—1
22141.167.72.220/3241.167.72.220 to 41.167.72.220—1
22241.167.72.221/3241.167.72.221 to 41.167.72.221—1
22341.167.72.222/3241.167.72.222 to 41.167.72.222—1
22441.167.72.223/3241.167.72.223 to 41.167.72.223—1
22541.167.72.224/3241.167.72.224 to 41.167.72.224—1
22641.167.72.225/3241.167.72.225 to 41.167.72.225—1
22741.167.72.226/3241.167.72.226 to 41.167.72.226—1
22841.167.72.227/3241.167.72.227 to 41.167.72.227—1
22941.167.72.228/3241.167.72.228 to 41.167.72.228—1
23041.167.72.229/3241.167.72.229 to 41.167.72.229—1
23141.167.72.230/3241.167.72.230 to 41.167.72.230—1
23241.167.72.231/3241.167.72.231 to 41.167.72.231—1
23341.167.72.232/3241.167.72.232 to 41.167.72.232—1
23441.167.72.233/3241.167.72.233 to 41.167.72.233—1
23541.167.72.234/3241.167.72.234 to 41.167.72.234—1
23641.167.72.235/3241.167.72.235 to 41.167.72.235—1
23741.167.72.236/3241.167.72.236 to 41.167.72.236—1
23841.167.72.237/3241.167.72.237 to 41.167.72.237—1
23941.167.72.238/3241.167.72.238 to 41.167.72.238—1
24041.167.72.239/3241.167.72.239 to 41.167.72.239—1
24141.167.72.240/3241.167.72.240 to 41.167.72.240—1
24241.167.72.241/3241.167.72.241 to 41.167.72.241—1
24341.167.72.242/3241.167.72.242 to 41.167.72.242—1
24441.167.72.243/3241.167.72.243 to 41.167.72.243—1
24541.167.72.244/3241.167.72.244 to 41.167.72.244—1
24641.167.72.245/3241.167.72.245 to 41.167.72.245—1
24741.167.72.246/3241.167.72.246 to 41.167.72.246—1
24841.167.72.247/3241.167.72.247 to 41.167.72.247—1
24941.167.72.248/3241.167.72.248 to 41.167.72.248—1
25041.167.72.249/3241.167.72.249 to 41.167.72.249—1
25141.167.72.250/3241.167.72.250 to 41.167.72.250—1
25241.167.72.251/3241.167.72.251 to 41.167.72.251—1
25341.167.72.252/3241.167.72.252 to 41.167.72.252—1
25441.167.72.253/3241.167.72.253 to 41.167.72.253—1
25541.167.72.254/3241.167.72.254 to 41.167.72.254—1
25641.167.72.255/3241.167.72.255 to 41.167.72.255—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.