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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.

Network80.22.96.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
80.22.96.0
Broadcast address
80.22.127.255
First usable
80.22.96.1
Last usable
80.22.127.254
Usable hosts
8,190 (8,192 less the network and broadcast addresses)
Subnet mask
255.255.224.0
Wildcard mask
0.0.31.255 (Cisco ACLs, OSPF)
Prefix length
/19
Type
Public public
Old class
A (default /8)
As numbers
Hex 50166000 · Integer 1343643648 to 1343651839
Reverse DNS zones
96.22.80.in-addr.arpa
97.22.80.in-addr.arpa
98.22.80.in-addr.arpa
99.22.80.in-addr.arpa
100.22.80.in-addr.arpa
101.22.80.in-addr.arpa
102.22.80.in-addr.arpa
103.22.80.in-addr.arpa
104.22.80.in-addr.arpa
105.22.80.in-addr.arpa
106.22.80.in-addr.arpa
107.22.80.in-addr.arpa
108.22.80.in-addr.arpa
109.22.80.in-addr.arpa
110.22.80.in-addr.arpa
111.22.80.in-addr.arpa
and 16 more
/19 is not on a 8-bit boundary, so it takes 32 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010000.00010110.01100000.0000000080.22.96.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network01010000.00010110.01100000.0000000080.22.96.0
Broadcast01010000.00010110.01111111.1111111180.22.127.255
Split into smaller subnets/30
/20 (2)/21 (4)/22 (8)/23 (16)/24 (32)/25 (64)/26 (128)/27 (256)/28 (512)/29 (1,024)/30 (2,048)/31 (4,096)

80.22.96.0/19 makes 2,048 subnets of /30; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
180.22.96.0/3080.22.96.1 to 80.22.96.280.22.96.32
280.22.96.4/3080.22.96.5 to 80.22.96.680.22.96.72
380.22.96.8/3080.22.96.9 to 80.22.96.1080.22.96.112
480.22.96.12/3080.22.96.13 to 80.22.96.1480.22.96.152
580.22.96.16/3080.22.96.17 to 80.22.96.1880.22.96.192
680.22.96.20/3080.22.96.21 to 80.22.96.2280.22.96.232
780.22.96.24/3080.22.96.25 to 80.22.96.2680.22.96.272
880.22.96.28/3080.22.96.29 to 80.22.96.3080.22.96.312
980.22.96.32/3080.22.96.33 to 80.22.96.3480.22.96.352
1080.22.96.36/3080.22.96.37 to 80.22.96.3880.22.96.392
1180.22.96.40/3080.22.96.41 to 80.22.96.4280.22.96.432
1280.22.96.44/3080.22.96.45 to 80.22.96.4680.22.96.472
1380.22.96.48/3080.22.96.49 to 80.22.96.5080.22.96.512
1480.22.96.52/3080.22.96.53 to 80.22.96.5480.22.96.552
1580.22.96.56/3080.22.96.57 to 80.22.96.5880.22.96.592
1680.22.96.60/3080.22.96.61 to 80.22.96.6280.22.96.632
1780.22.96.64/3080.22.96.65 to 80.22.96.6680.22.96.672
1880.22.96.68/3080.22.96.69 to 80.22.96.7080.22.96.712
1980.22.96.72/3080.22.96.73 to 80.22.96.7480.22.96.752
2080.22.96.76/3080.22.96.77 to 80.22.96.7880.22.96.792
2180.22.96.80/3080.22.96.81 to 80.22.96.8280.22.96.832
2280.22.96.84/3080.22.96.85 to 80.22.96.8680.22.96.872
2380.22.96.88/3080.22.96.89 to 80.22.96.9080.22.96.912
2480.22.96.92/3080.22.96.93 to 80.22.96.9480.22.96.952
2580.22.96.96/3080.22.96.97 to 80.22.96.9880.22.96.992
2680.22.96.100/3080.22.96.101 to 80.22.96.10280.22.96.1032
2780.22.96.104/3080.22.96.105 to 80.22.96.10680.22.96.1072
2880.22.96.108/3080.22.96.109 to 80.22.96.11080.22.96.1112
2980.22.96.112/3080.22.96.113 to 80.22.96.11480.22.96.1152
3080.22.96.116/3080.22.96.117 to 80.22.96.11880.22.96.1192
3180.22.96.120/3080.22.96.121 to 80.22.96.12280.22.96.1232
3280.22.96.124/3080.22.96.125 to 80.22.96.12680.22.96.1272
3380.22.96.128/3080.22.96.129 to 80.22.96.13080.22.96.1312
3480.22.96.132/3080.22.96.133 to 80.22.96.13480.22.96.1352
3580.22.96.136/3080.22.96.137 to 80.22.96.13880.22.96.1392
3680.22.96.140/3080.22.96.141 to 80.22.96.14280.22.96.1432
3780.22.96.144/3080.22.96.145 to 80.22.96.14680.22.96.1472
3880.22.96.148/3080.22.96.149 to 80.22.96.15080.22.96.1512
3980.22.96.152/3080.22.96.153 to 80.22.96.15480.22.96.1552
4080.22.96.156/3080.22.96.157 to 80.22.96.15880.22.96.1592
4180.22.96.160/3080.22.96.161 to 80.22.96.16280.22.96.1632
4280.22.96.164/3080.22.96.165 to 80.22.96.16680.22.96.1672
4380.22.96.168/3080.22.96.169 to 80.22.96.17080.22.96.1712
4480.22.96.172/3080.22.96.173 to 80.22.96.17480.22.96.1752
4580.22.96.176/3080.22.96.177 to 80.22.96.17880.22.96.1792
4680.22.96.180/3080.22.96.181 to 80.22.96.18280.22.96.1832
4780.22.96.184/3080.22.96.185 to 80.22.96.18680.22.96.1872
4880.22.96.188/3080.22.96.189 to 80.22.96.19080.22.96.1912
4980.22.96.192/3080.22.96.193 to 80.22.96.19480.22.96.1952
5080.22.96.196/3080.22.96.197 to 80.22.96.19880.22.96.1992
5180.22.96.200/3080.22.96.201 to 80.22.96.20280.22.96.2032
5280.22.96.204/3080.22.96.205 to 80.22.96.20680.22.96.2072
5380.22.96.208/3080.22.96.209 to 80.22.96.21080.22.96.2112
5480.22.96.212/3080.22.96.213 to 80.22.96.21480.22.96.2152
5580.22.96.216/3080.22.96.217 to 80.22.96.21880.22.96.2192
5680.22.96.220/3080.22.96.221 to 80.22.96.22280.22.96.2232
5780.22.96.224/3080.22.96.225 to 80.22.96.22680.22.96.2272
5880.22.96.228/3080.22.96.229 to 80.22.96.23080.22.96.2312
5980.22.96.232/3080.22.96.233 to 80.22.96.23480.22.96.2352
6080.22.96.236/3080.22.96.237 to 80.22.96.23880.22.96.2392
6180.22.96.240/3080.22.96.241 to 80.22.96.24280.22.96.2432
6280.22.96.244/3080.22.96.245 to 80.22.96.24680.22.96.2472
6380.22.96.248/3080.22.96.249 to 80.22.96.25080.22.96.2512
6480.22.96.252/3080.22.96.253 to 80.22.96.25480.22.96.2552
6580.22.97.0/3080.22.97.1 to 80.22.97.280.22.97.32
6680.22.97.4/3080.22.97.5 to 80.22.97.680.22.97.72
6780.22.97.8/3080.22.97.9 to 80.22.97.1080.22.97.112
6880.22.97.12/3080.22.97.13 to 80.22.97.1480.22.97.152
6980.22.97.16/3080.22.97.17 to 80.22.97.1880.22.97.192
7080.22.97.20/3080.22.97.21 to 80.22.97.2280.22.97.232
7180.22.97.24/3080.22.97.25 to 80.22.97.2680.22.97.272
7280.22.97.28/3080.22.97.29 to 80.22.97.3080.22.97.312
7380.22.97.32/3080.22.97.33 to 80.22.97.3480.22.97.352
7480.22.97.36/3080.22.97.37 to 80.22.97.3880.22.97.392
7580.22.97.40/3080.22.97.41 to 80.22.97.4280.22.97.432
7680.22.97.44/3080.22.97.45 to 80.22.97.4680.22.97.472
7780.22.97.48/3080.22.97.49 to 80.22.97.5080.22.97.512
7880.22.97.52/3080.22.97.53 to 80.22.97.5480.22.97.552
7980.22.97.56/3080.22.97.57 to 80.22.97.5880.22.97.592
8080.22.97.60/3080.22.97.61 to 80.22.97.6280.22.97.632
8180.22.97.64/3080.22.97.65 to 80.22.97.6680.22.97.672
8280.22.97.68/3080.22.97.69 to 80.22.97.7080.22.97.712
8380.22.97.72/3080.22.97.73 to 80.22.97.7480.22.97.752
8480.22.97.76/3080.22.97.77 to 80.22.97.7880.22.97.792
8580.22.97.80/3080.22.97.81 to 80.22.97.8280.22.97.832
8680.22.97.84/3080.22.97.85 to 80.22.97.8680.22.97.872
8780.22.97.88/3080.22.97.89 to 80.22.97.9080.22.97.912
8880.22.97.92/3080.22.97.93 to 80.22.97.9480.22.97.952
8980.22.97.96/3080.22.97.97 to 80.22.97.9880.22.97.992
9080.22.97.100/3080.22.97.101 to 80.22.97.10280.22.97.1032
9180.22.97.104/3080.22.97.105 to 80.22.97.10680.22.97.1072
9280.22.97.108/3080.22.97.109 to 80.22.97.11080.22.97.1112
9380.22.97.112/3080.22.97.113 to 80.22.97.11480.22.97.1152
9480.22.97.116/3080.22.97.117 to 80.22.97.11880.22.97.1192
9580.22.97.120/3080.22.97.121 to 80.22.97.12280.22.97.1232
9680.22.97.124/3080.22.97.125 to 80.22.97.12680.22.97.1272
9780.22.97.128/3080.22.97.129 to 80.22.97.13080.22.97.1312
9880.22.97.132/3080.22.97.133 to 80.22.97.13480.22.97.1352
9980.22.97.136/3080.22.97.137 to 80.22.97.13880.22.97.1392
10080.22.97.140/3080.22.97.141 to 80.22.97.14280.22.97.1432
10180.22.97.144/3080.22.97.145 to 80.22.97.14680.22.97.1472
10280.22.97.148/3080.22.97.149 to 80.22.97.15080.22.97.1512
10380.22.97.152/3080.22.97.153 to 80.22.97.15480.22.97.1552
10480.22.97.156/3080.22.97.157 to 80.22.97.15880.22.97.1592
10580.22.97.160/3080.22.97.161 to 80.22.97.16280.22.97.1632
10680.22.97.164/3080.22.97.165 to 80.22.97.16680.22.97.1672
10780.22.97.168/3080.22.97.169 to 80.22.97.17080.22.97.1712
10880.22.97.172/3080.22.97.173 to 80.22.97.17480.22.97.1752
10980.22.97.176/3080.22.97.177 to 80.22.97.17880.22.97.1792
11080.22.97.180/3080.22.97.181 to 80.22.97.18280.22.97.1832
11180.22.97.184/3080.22.97.185 to 80.22.97.18680.22.97.1872
11280.22.97.188/3080.22.97.189 to 80.22.97.19080.22.97.1912
11380.22.97.192/3080.22.97.193 to 80.22.97.19480.22.97.1952
11480.22.97.196/3080.22.97.197 to 80.22.97.19880.22.97.1992
11580.22.97.200/3080.22.97.201 to 80.22.97.20280.22.97.2032
11680.22.97.204/3080.22.97.205 to 80.22.97.20680.22.97.2072
11780.22.97.208/3080.22.97.209 to 80.22.97.21080.22.97.2112
11880.22.97.212/3080.22.97.213 to 80.22.97.21480.22.97.2152
11980.22.97.216/3080.22.97.217 to 80.22.97.21880.22.97.2192
12080.22.97.220/3080.22.97.221 to 80.22.97.22280.22.97.2232
12180.22.97.224/3080.22.97.225 to 80.22.97.22680.22.97.2272
12280.22.97.228/3080.22.97.229 to 80.22.97.23080.22.97.2312
12380.22.97.232/3080.22.97.233 to 80.22.97.23480.22.97.2352
12480.22.97.236/3080.22.97.237 to 80.22.97.23880.22.97.2392
12580.22.97.240/3080.22.97.241 to 80.22.97.24280.22.97.2432
12680.22.97.244/3080.22.97.245 to 80.22.97.24680.22.97.2472
12780.22.97.248/3080.22.97.249 to 80.22.97.25080.22.97.2512
12880.22.97.252/3080.22.97.253 to 80.22.97.25480.22.97.2552
12980.22.98.0/3080.22.98.1 to 80.22.98.280.22.98.32
13080.22.98.4/3080.22.98.5 to 80.22.98.680.22.98.72
13180.22.98.8/3080.22.98.9 to 80.22.98.1080.22.98.112
13280.22.98.12/3080.22.98.13 to 80.22.98.1480.22.98.152
13380.22.98.16/3080.22.98.17 to 80.22.98.1880.22.98.192
13480.22.98.20/3080.22.98.21 to 80.22.98.2280.22.98.232
13580.22.98.24/3080.22.98.25 to 80.22.98.2680.22.98.272
13680.22.98.28/3080.22.98.29 to 80.22.98.3080.22.98.312
13780.22.98.32/3080.22.98.33 to 80.22.98.3480.22.98.352
13880.22.98.36/3080.22.98.37 to 80.22.98.3880.22.98.392
13980.22.98.40/3080.22.98.41 to 80.22.98.4280.22.98.432
14080.22.98.44/3080.22.98.45 to 80.22.98.4680.22.98.472
14180.22.98.48/3080.22.98.49 to 80.22.98.5080.22.98.512
14280.22.98.52/3080.22.98.53 to 80.22.98.5480.22.98.552
14380.22.98.56/3080.22.98.57 to 80.22.98.5880.22.98.592
14480.22.98.60/3080.22.98.61 to 80.22.98.6280.22.98.632
14580.22.98.64/3080.22.98.65 to 80.22.98.6680.22.98.672
14680.22.98.68/3080.22.98.69 to 80.22.98.7080.22.98.712
14780.22.98.72/3080.22.98.73 to 80.22.98.7480.22.98.752
14880.22.98.76/3080.22.98.77 to 80.22.98.7880.22.98.792
14980.22.98.80/3080.22.98.81 to 80.22.98.8280.22.98.832
15080.22.98.84/3080.22.98.85 to 80.22.98.8680.22.98.872
15180.22.98.88/3080.22.98.89 to 80.22.98.9080.22.98.912
15280.22.98.92/3080.22.98.93 to 80.22.98.9480.22.98.952
15380.22.98.96/3080.22.98.97 to 80.22.98.9880.22.98.992
15480.22.98.100/3080.22.98.101 to 80.22.98.10280.22.98.1032
15580.22.98.104/3080.22.98.105 to 80.22.98.10680.22.98.1072
15680.22.98.108/3080.22.98.109 to 80.22.98.11080.22.98.1112
15780.22.98.112/3080.22.98.113 to 80.22.98.11480.22.98.1152
15880.22.98.116/3080.22.98.117 to 80.22.98.11880.22.98.1192
15980.22.98.120/3080.22.98.121 to 80.22.98.12280.22.98.1232
16080.22.98.124/3080.22.98.125 to 80.22.98.12680.22.98.1272
16180.22.98.128/3080.22.98.129 to 80.22.98.13080.22.98.1312
16280.22.98.132/3080.22.98.133 to 80.22.98.13480.22.98.1352
16380.22.98.136/3080.22.98.137 to 80.22.98.13880.22.98.1392
16480.22.98.140/3080.22.98.141 to 80.22.98.14280.22.98.1432
16580.22.98.144/3080.22.98.145 to 80.22.98.14680.22.98.1472
16680.22.98.148/3080.22.98.149 to 80.22.98.15080.22.98.1512
16780.22.98.152/3080.22.98.153 to 80.22.98.15480.22.98.1552
16880.22.98.156/3080.22.98.157 to 80.22.98.15880.22.98.1592
16980.22.98.160/3080.22.98.161 to 80.22.98.16280.22.98.1632
17080.22.98.164/3080.22.98.165 to 80.22.98.16680.22.98.1672
17180.22.98.168/3080.22.98.169 to 80.22.98.17080.22.98.1712
17280.22.98.172/3080.22.98.173 to 80.22.98.17480.22.98.1752
17380.22.98.176/3080.22.98.177 to 80.22.98.17880.22.98.1792
17480.22.98.180/3080.22.98.181 to 80.22.98.18280.22.98.1832
17580.22.98.184/3080.22.98.185 to 80.22.98.18680.22.98.1872
17680.22.98.188/3080.22.98.189 to 80.22.98.19080.22.98.1912
17780.22.98.192/3080.22.98.193 to 80.22.98.19480.22.98.1952
17880.22.98.196/3080.22.98.197 to 80.22.98.19880.22.98.1992
17980.22.98.200/3080.22.98.201 to 80.22.98.20280.22.98.2032
18080.22.98.204/3080.22.98.205 to 80.22.98.20680.22.98.2072
18180.22.98.208/3080.22.98.209 to 80.22.98.21080.22.98.2112
18280.22.98.212/3080.22.98.213 to 80.22.98.21480.22.98.2152
18380.22.98.216/3080.22.98.217 to 80.22.98.21880.22.98.2192
18480.22.98.220/3080.22.98.221 to 80.22.98.22280.22.98.2232
18580.22.98.224/3080.22.98.225 to 80.22.98.22680.22.98.2272
18680.22.98.228/3080.22.98.229 to 80.22.98.23080.22.98.2312
18780.22.98.232/3080.22.98.233 to 80.22.98.23480.22.98.2352
18880.22.98.236/3080.22.98.237 to 80.22.98.23880.22.98.2392
18980.22.98.240/3080.22.98.241 to 80.22.98.24280.22.98.2432
19080.22.98.244/3080.22.98.245 to 80.22.98.24680.22.98.2472
19180.22.98.248/3080.22.98.249 to 80.22.98.25080.22.98.2512
19280.22.98.252/3080.22.98.253 to 80.22.98.25480.22.98.2552
19380.22.99.0/3080.22.99.1 to 80.22.99.280.22.99.32
19480.22.99.4/3080.22.99.5 to 80.22.99.680.22.99.72
19580.22.99.8/3080.22.99.9 to 80.22.99.1080.22.99.112
19680.22.99.12/3080.22.99.13 to 80.22.99.1480.22.99.152
19780.22.99.16/3080.22.99.17 to 80.22.99.1880.22.99.192
19880.22.99.20/3080.22.99.21 to 80.22.99.2280.22.99.232
19980.22.99.24/3080.22.99.25 to 80.22.99.2680.22.99.272
20080.22.99.28/3080.22.99.29 to 80.22.99.3080.22.99.312
20180.22.99.32/3080.22.99.33 to 80.22.99.3480.22.99.352
20280.22.99.36/3080.22.99.37 to 80.22.99.3880.22.99.392
20380.22.99.40/3080.22.99.41 to 80.22.99.4280.22.99.432
20480.22.99.44/3080.22.99.45 to 80.22.99.4680.22.99.472
20580.22.99.48/3080.22.99.49 to 80.22.99.5080.22.99.512
20680.22.99.52/3080.22.99.53 to 80.22.99.5480.22.99.552
20780.22.99.56/3080.22.99.57 to 80.22.99.5880.22.99.592
20880.22.99.60/3080.22.99.61 to 80.22.99.6280.22.99.632
20980.22.99.64/3080.22.99.65 to 80.22.99.6680.22.99.672
21080.22.99.68/3080.22.99.69 to 80.22.99.7080.22.99.712
21180.22.99.72/3080.22.99.73 to 80.22.99.7480.22.99.752
21280.22.99.76/3080.22.99.77 to 80.22.99.7880.22.99.792
21380.22.99.80/3080.22.99.81 to 80.22.99.8280.22.99.832
21480.22.99.84/3080.22.99.85 to 80.22.99.8680.22.99.872
21580.22.99.88/3080.22.99.89 to 80.22.99.9080.22.99.912
21680.22.99.92/3080.22.99.93 to 80.22.99.9480.22.99.952
21780.22.99.96/3080.22.99.97 to 80.22.99.9880.22.99.992
21880.22.99.100/3080.22.99.101 to 80.22.99.10280.22.99.1032
21980.22.99.104/3080.22.99.105 to 80.22.99.10680.22.99.1072
22080.22.99.108/3080.22.99.109 to 80.22.99.11080.22.99.1112
22180.22.99.112/3080.22.99.113 to 80.22.99.11480.22.99.1152
22280.22.99.116/3080.22.99.117 to 80.22.99.11880.22.99.1192
22380.22.99.120/3080.22.99.121 to 80.22.99.12280.22.99.1232
22480.22.99.124/3080.22.99.125 to 80.22.99.12680.22.99.1272
22580.22.99.128/3080.22.99.129 to 80.22.99.13080.22.99.1312
22680.22.99.132/3080.22.99.133 to 80.22.99.13480.22.99.1352
22780.22.99.136/3080.22.99.137 to 80.22.99.13880.22.99.1392
22880.22.99.140/3080.22.99.141 to 80.22.99.14280.22.99.1432
22980.22.99.144/3080.22.99.145 to 80.22.99.14680.22.99.1472
23080.22.99.148/3080.22.99.149 to 80.22.99.15080.22.99.1512
23180.22.99.152/3080.22.99.153 to 80.22.99.15480.22.99.1552
23280.22.99.156/3080.22.99.157 to 80.22.99.15880.22.99.1592
23380.22.99.160/3080.22.99.161 to 80.22.99.16280.22.99.1632
23480.22.99.164/3080.22.99.165 to 80.22.99.16680.22.99.1672
23580.22.99.168/3080.22.99.169 to 80.22.99.17080.22.99.1712
23680.22.99.172/3080.22.99.173 to 80.22.99.17480.22.99.1752
23780.22.99.176/3080.22.99.177 to 80.22.99.17880.22.99.1792
23880.22.99.180/3080.22.99.181 to 80.22.99.18280.22.99.1832
23980.22.99.184/3080.22.99.185 to 80.22.99.18680.22.99.1872
24080.22.99.188/3080.22.99.189 to 80.22.99.19080.22.99.1912
24180.22.99.192/3080.22.99.193 to 80.22.99.19480.22.99.1952
24280.22.99.196/3080.22.99.197 to 80.22.99.19880.22.99.1992
24380.22.99.200/3080.22.99.201 to 80.22.99.20280.22.99.2032
24480.22.99.204/3080.22.99.205 to 80.22.99.20680.22.99.2072
24580.22.99.208/3080.22.99.209 to 80.22.99.21080.22.99.2112
24680.22.99.212/3080.22.99.213 to 80.22.99.21480.22.99.2152
24780.22.99.216/3080.22.99.217 to 80.22.99.21880.22.99.2192
24880.22.99.220/3080.22.99.221 to 80.22.99.22280.22.99.2232
24980.22.99.224/3080.22.99.225 to 80.22.99.22680.22.99.2272
25080.22.99.228/3080.22.99.229 to 80.22.99.23080.22.99.2312
25180.22.99.232/3080.22.99.233 to 80.22.99.23480.22.99.2352
25280.22.99.236/3080.22.99.237 to 80.22.99.23880.22.99.2392
25380.22.99.240/3080.22.99.241 to 80.22.99.24280.22.99.2432
25480.22.99.244/3080.22.99.245 to 80.22.99.24680.22.99.2472
25580.22.99.248/3080.22.99.249 to 80.22.99.25080.22.99.2512
25680.22.99.252/3080.22.99.253 to 80.22.99.25480.22.99.2552

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

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.