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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.

Network33.2.44.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
33.2.44.0
Broadcast address
33.2.47.255
First usable
33.2.44.1
Last usable
33.2.47.254
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 21022C00 · Integer 553790464 to 553791487
Reverse DNS zones
44.2.33.in-addr.arpa
45.2.33.in-addr.arpa
46.2.33.in-addr.arpa
47.2.33.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
Address00100001.00000010.00101100.0000000033.2.44.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network00100001.00000010.00101100.0000000033.2.44.0
Broadcast00100001.00000010.00101111.1111111133.2.47.255
Split into smaller subnets/30

33.2.44.0/22 makes 256 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
133.2.44.0/3033.2.44.1 to 33.2.44.233.2.44.32
233.2.44.4/3033.2.44.5 to 33.2.44.633.2.44.72
333.2.44.8/3033.2.44.9 to 33.2.44.1033.2.44.112
433.2.44.12/3033.2.44.13 to 33.2.44.1433.2.44.152
533.2.44.16/3033.2.44.17 to 33.2.44.1833.2.44.192
633.2.44.20/3033.2.44.21 to 33.2.44.2233.2.44.232
733.2.44.24/3033.2.44.25 to 33.2.44.2633.2.44.272
833.2.44.28/3033.2.44.29 to 33.2.44.3033.2.44.312
933.2.44.32/3033.2.44.33 to 33.2.44.3433.2.44.352
1033.2.44.36/3033.2.44.37 to 33.2.44.3833.2.44.392
1133.2.44.40/3033.2.44.41 to 33.2.44.4233.2.44.432
1233.2.44.44/3033.2.44.45 to 33.2.44.4633.2.44.472
1333.2.44.48/3033.2.44.49 to 33.2.44.5033.2.44.512
1433.2.44.52/3033.2.44.53 to 33.2.44.5433.2.44.552
1533.2.44.56/3033.2.44.57 to 33.2.44.5833.2.44.592
1633.2.44.60/3033.2.44.61 to 33.2.44.6233.2.44.632
1733.2.44.64/3033.2.44.65 to 33.2.44.6633.2.44.672
1833.2.44.68/3033.2.44.69 to 33.2.44.7033.2.44.712
1933.2.44.72/3033.2.44.73 to 33.2.44.7433.2.44.752
2033.2.44.76/3033.2.44.77 to 33.2.44.7833.2.44.792
2133.2.44.80/3033.2.44.81 to 33.2.44.8233.2.44.832
2233.2.44.84/3033.2.44.85 to 33.2.44.8633.2.44.872
2333.2.44.88/3033.2.44.89 to 33.2.44.9033.2.44.912
2433.2.44.92/3033.2.44.93 to 33.2.44.9433.2.44.952
2533.2.44.96/3033.2.44.97 to 33.2.44.9833.2.44.992
2633.2.44.100/3033.2.44.101 to 33.2.44.10233.2.44.1032
2733.2.44.104/3033.2.44.105 to 33.2.44.10633.2.44.1072
2833.2.44.108/3033.2.44.109 to 33.2.44.11033.2.44.1112
2933.2.44.112/3033.2.44.113 to 33.2.44.11433.2.44.1152
3033.2.44.116/3033.2.44.117 to 33.2.44.11833.2.44.1192
3133.2.44.120/3033.2.44.121 to 33.2.44.12233.2.44.1232
3233.2.44.124/3033.2.44.125 to 33.2.44.12633.2.44.1272
3333.2.44.128/3033.2.44.129 to 33.2.44.13033.2.44.1312
3433.2.44.132/3033.2.44.133 to 33.2.44.13433.2.44.1352
3533.2.44.136/3033.2.44.137 to 33.2.44.13833.2.44.1392
3633.2.44.140/3033.2.44.141 to 33.2.44.14233.2.44.1432
3733.2.44.144/3033.2.44.145 to 33.2.44.14633.2.44.1472
3833.2.44.148/3033.2.44.149 to 33.2.44.15033.2.44.1512
3933.2.44.152/3033.2.44.153 to 33.2.44.15433.2.44.1552
4033.2.44.156/3033.2.44.157 to 33.2.44.15833.2.44.1592
4133.2.44.160/3033.2.44.161 to 33.2.44.16233.2.44.1632
4233.2.44.164/3033.2.44.165 to 33.2.44.16633.2.44.1672
4333.2.44.168/3033.2.44.169 to 33.2.44.17033.2.44.1712
4433.2.44.172/3033.2.44.173 to 33.2.44.17433.2.44.1752
4533.2.44.176/3033.2.44.177 to 33.2.44.17833.2.44.1792
4633.2.44.180/3033.2.44.181 to 33.2.44.18233.2.44.1832
4733.2.44.184/3033.2.44.185 to 33.2.44.18633.2.44.1872
4833.2.44.188/3033.2.44.189 to 33.2.44.19033.2.44.1912
4933.2.44.192/3033.2.44.193 to 33.2.44.19433.2.44.1952
5033.2.44.196/3033.2.44.197 to 33.2.44.19833.2.44.1992
5133.2.44.200/3033.2.44.201 to 33.2.44.20233.2.44.2032
5233.2.44.204/3033.2.44.205 to 33.2.44.20633.2.44.2072
5333.2.44.208/3033.2.44.209 to 33.2.44.21033.2.44.2112
5433.2.44.212/3033.2.44.213 to 33.2.44.21433.2.44.2152
5533.2.44.216/3033.2.44.217 to 33.2.44.21833.2.44.2192
5633.2.44.220/3033.2.44.221 to 33.2.44.22233.2.44.2232
5733.2.44.224/3033.2.44.225 to 33.2.44.22633.2.44.2272
5833.2.44.228/3033.2.44.229 to 33.2.44.23033.2.44.2312
5933.2.44.232/3033.2.44.233 to 33.2.44.23433.2.44.2352
6033.2.44.236/3033.2.44.237 to 33.2.44.23833.2.44.2392
6133.2.44.240/3033.2.44.241 to 33.2.44.24233.2.44.2432
6233.2.44.244/3033.2.44.245 to 33.2.44.24633.2.44.2472
6333.2.44.248/3033.2.44.249 to 33.2.44.25033.2.44.2512
6433.2.44.252/3033.2.44.253 to 33.2.44.25433.2.44.2552
6533.2.45.0/3033.2.45.1 to 33.2.45.233.2.45.32
6633.2.45.4/3033.2.45.5 to 33.2.45.633.2.45.72
6733.2.45.8/3033.2.45.9 to 33.2.45.1033.2.45.112
6833.2.45.12/3033.2.45.13 to 33.2.45.1433.2.45.152
6933.2.45.16/3033.2.45.17 to 33.2.45.1833.2.45.192
7033.2.45.20/3033.2.45.21 to 33.2.45.2233.2.45.232
7133.2.45.24/3033.2.45.25 to 33.2.45.2633.2.45.272
7233.2.45.28/3033.2.45.29 to 33.2.45.3033.2.45.312
7333.2.45.32/3033.2.45.33 to 33.2.45.3433.2.45.352
7433.2.45.36/3033.2.45.37 to 33.2.45.3833.2.45.392
7533.2.45.40/3033.2.45.41 to 33.2.45.4233.2.45.432
7633.2.45.44/3033.2.45.45 to 33.2.45.4633.2.45.472
7733.2.45.48/3033.2.45.49 to 33.2.45.5033.2.45.512
7833.2.45.52/3033.2.45.53 to 33.2.45.5433.2.45.552
7933.2.45.56/3033.2.45.57 to 33.2.45.5833.2.45.592
8033.2.45.60/3033.2.45.61 to 33.2.45.6233.2.45.632
8133.2.45.64/3033.2.45.65 to 33.2.45.6633.2.45.672
8233.2.45.68/3033.2.45.69 to 33.2.45.7033.2.45.712
8333.2.45.72/3033.2.45.73 to 33.2.45.7433.2.45.752
8433.2.45.76/3033.2.45.77 to 33.2.45.7833.2.45.792
8533.2.45.80/3033.2.45.81 to 33.2.45.8233.2.45.832
8633.2.45.84/3033.2.45.85 to 33.2.45.8633.2.45.872
8733.2.45.88/3033.2.45.89 to 33.2.45.9033.2.45.912
8833.2.45.92/3033.2.45.93 to 33.2.45.9433.2.45.952
8933.2.45.96/3033.2.45.97 to 33.2.45.9833.2.45.992
9033.2.45.100/3033.2.45.101 to 33.2.45.10233.2.45.1032
9133.2.45.104/3033.2.45.105 to 33.2.45.10633.2.45.1072
9233.2.45.108/3033.2.45.109 to 33.2.45.11033.2.45.1112
9333.2.45.112/3033.2.45.113 to 33.2.45.11433.2.45.1152
9433.2.45.116/3033.2.45.117 to 33.2.45.11833.2.45.1192
9533.2.45.120/3033.2.45.121 to 33.2.45.12233.2.45.1232
9633.2.45.124/3033.2.45.125 to 33.2.45.12633.2.45.1272
9733.2.45.128/3033.2.45.129 to 33.2.45.13033.2.45.1312
9833.2.45.132/3033.2.45.133 to 33.2.45.13433.2.45.1352
9933.2.45.136/3033.2.45.137 to 33.2.45.13833.2.45.1392
10033.2.45.140/3033.2.45.141 to 33.2.45.14233.2.45.1432
10133.2.45.144/3033.2.45.145 to 33.2.45.14633.2.45.1472
10233.2.45.148/3033.2.45.149 to 33.2.45.15033.2.45.1512
10333.2.45.152/3033.2.45.153 to 33.2.45.15433.2.45.1552
10433.2.45.156/3033.2.45.157 to 33.2.45.15833.2.45.1592
10533.2.45.160/3033.2.45.161 to 33.2.45.16233.2.45.1632
10633.2.45.164/3033.2.45.165 to 33.2.45.16633.2.45.1672
10733.2.45.168/3033.2.45.169 to 33.2.45.17033.2.45.1712
10833.2.45.172/3033.2.45.173 to 33.2.45.17433.2.45.1752
10933.2.45.176/3033.2.45.177 to 33.2.45.17833.2.45.1792
11033.2.45.180/3033.2.45.181 to 33.2.45.18233.2.45.1832
11133.2.45.184/3033.2.45.185 to 33.2.45.18633.2.45.1872
11233.2.45.188/3033.2.45.189 to 33.2.45.19033.2.45.1912
11333.2.45.192/3033.2.45.193 to 33.2.45.19433.2.45.1952
11433.2.45.196/3033.2.45.197 to 33.2.45.19833.2.45.1992
11533.2.45.200/3033.2.45.201 to 33.2.45.20233.2.45.2032
11633.2.45.204/3033.2.45.205 to 33.2.45.20633.2.45.2072
11733.2.45.208/3033.2.45.209 to 33.2.45.21033.2.45.2112
11833.2.45.212/3033.2.45.213 to 33.2.45.21433.2.45.2152
11933.2.45.216/3033.2.45.217 to 33.2.45.21833.2.45.2192
12033.2.45.220/3033.2.45.221 to 33.2.45.22233.2.45.2232
12133.2.45.224/3033.2.45.225 to 33.2.45.22633.2.45.2272
12233.2.45.228/3033.2.45.229 to 33.2.45.23033.2.45.2312
12333.2.45.232/3033.2.45.233 to 33.2.45.23433.2.45.2352
12433.2.45.236/3033.2.45.237 to 33.2.45.23833.2.45.2392
12533.2.45.240/3033.2.45.241 to 33.2.45.24233.2.45.2432
12633.2.45.244/3033.2.45.245 to 33.2.45.24633.2.45.2472
12733.2.45.248/3033.2.45.249 to 33.2.45.25033.2.45.2512
12833.2.45.252/3033.2.45.253 to 33.2.45.25433.2.45.2552
12933.2.46.0/3033.2.46.1 to 33.2.46.233.2.46.32
13033.2.46.4/3033.2.46.5 to 33.2.46.633.2.46.72
13133.2.46.8/3033.2.46.9 to 33.2.46.1033.2.46.112
13233.2.46.12/3033.2.46.13 to 33.2.46.1433.2.46.152
13333.2.46.16/3033.2.46.17 to 33.2.46.1833.2.46.192
13433.2.46.20/3033.2.46.21 to 33.2.46.2233.2.46.232
13533.2.46.24/3033.2.46.25 to 33.2.46.2633.2.46.272
13633.2.46.28/3033.2.46.29 to 33.2.46.3033.2.46.312
13733.2.46.32/3033.2.46.33 to 33.2.46.3433.2.46.352
13833.2.46.36/3033.2.46.37 to 33.2.46.3833.2.46.392
13933.2.46.40/3033.2.46.41 to 33.2.46.4233.2.46.432
14033.2.46.44/3033.2.46.45 to 33.2.46.4633.2.46.472
14133.2.46.48/3033.2.46.49 to 33.2.46.5033.2.46.512
14233.2.46.52/3033.2.46.53 to 33.2.46.5433.2.46.552
14333.2.46.56/3033.2.46.57 to 33.2.46.5833.2.46.592
14433.2.46.60/3033.2.46.61 to 33.2.46.6233.2.46.632
14533.2.46.64/3033.2.46.65 to 33.2.46.6633.2.46.672
14633.2.46.68/3033.2.46.69 to 33.2.46.7033.2.46.712
14733.2.46.72/3033.2.46.73 to 33.2.46.7433.2.46.752
14833.2.46.76/3033.2.46.77 to 33.2.46.7833.2.46.792
14933.2.46.80/3033.2.46.81 to 33.2.46.8233.2.46.832
15033.2.46.84/3033.2.46.85 to 33.2.46.8633.2.46.872
15133.2.46.88/3033.2.46.89 to 33.2.46.9033.2.46.912
15233.2.46.92/3033.2.46.93 to 33.2.46.9433.2.46.952
15333.2.46.96/3033.2.46.97 to 33.2.46.9833.2.46.992
15433.2.46.100/3033.2.46.101 to 33.2.46.10233.2.46.1032
15533.2.46.104/3033.2.46.105 to 33.2.46.10633.2.46.1072
15633.2.46.108/3033.2.46.109 to 33.2.46.11033.2.46.1112
15733.2.46.112/3033.2.46.113 to 33.2.46.11433.2.46.1152
15833.2.46.116/3033.2.46.117 to 33.2.46.11833.2.46.1192
15933.2.46.120/3033.2.46.121 to 33.2.46.12233.2.46.1232
16033.2.46.124/3033.2.46.125 to 33.2.46.12633.2.46.1272
16133.2.46.128/3033.2.46.129 to 33.2.46.13033.2.46.1312
16233.2.46.132/3033.2.46.133 to 33.2.46.13433.2.46.1352
16333.2.46.136/3033.2.46.137 to 33.2.46.13833.2.46.1392
16433.2.46.140/3033.2.46.141 to 33.2.46.14233.2.46.1432
16533.2.46.144/3033.2.46.145 to 33.2.46.14633.2.46.1472
16633.2.46.148/3033.2.46.149 to 33.2.46.15033.2.46.1512
16733.2.46.152/3033.2.46.153 to 33.2.46.15433.2.46.1552
16833.2.46.156/3033.2.46.157 to 33.2.46.15833.2.46.1592
16933.2.46.160/3033.2.46.161 to 33.2.46.16233.2.46.1632
17033.2.46.164/3033.2.46.165 to 33.2.46.16633.2.46.1672
17133.2.46.168/3033.2.46.169 to 33.2.46.17033.2.46.1712
17233.2.46.172/3033.2.46.173 to 33.2.46.17433.2.46.1752
17333.2.46.176/3033.2.46.177 to 33.2.46.17833.2.46.1792
17433.2.46.180/3033.2.46.181 to 33.2.46.18233.2.46.1832
17533.2.46.184/3033.2.46.185 to 33.2.46.18633.2.46.1872
17633.2.46.188/3033.2.46.189 to 33.2.46.19033.2.46.1912
17733.2.46.192/3033.2.46.193 to 33.2.46.19433.2.46.1952
17833.2.46.196/3033.2.46.197 to 33.2.46.19833.2.46.1992
17933.2.46.200/3033.2.46.201 to 33.2.46.20233.2.46.2032
18033.2.46.204/3033.2.46.205 to 33.2.46.20633.2.46.2072
18133.2.46.208/3033.2.46.209 to 33.2.46.21033.2.46.2112
18233.2.46.212/3033.2.46.213 to 33.2.46.21433.2.46.2152
18333.2.46.216/3033.2.46.217 to 33.2.46.21833.2.46.2192
18433.2.46.220/3033.2.46.221 to 33.2.46.22233.2.46.2232
18533.2.46.224/3033.2.46.225 to 33.2.46.22633.2.46.2272
18633.2.46.228/3033.2.46.229 to 33.2.46.23033.2.46.2312
18733.2.46.232/3033.2.46.233 to 33.2.46.23433.2.46.2352
18833.2.46.236/3033.2.46.237 to 33.2.46.23833.2.46.2392
18933.2.46.240/3033.2.46.241 to 33.2.46.24233.2.46.2432
19033.2.46.244/3033.2.46.245 to 33.2.46.24633.2.46.2472
19133.2.46.248/3033.2.46.249 to 33.2.46.25033.2.46.2512
19233.2.46.252/3033.2.46.253 to 33.2.46.25433.2.46.2552
19333.2.47.0/3033.2.47.1 to 33.2.47.233.2.47.32
19433.2.47.4/3033.2.47.5 to 33.2.47.633.2.47.72
19533.2.47.8/3033.2.47.9 to 33.2.47.1033.2.47.112
19633.2.47.12/3033.2.47.13 to 33.2.47.1433.2.47.152
19733.2.47.16/3033.2.47.17 to 33.2.47.1833.2.47.192
19833.2.47.20/3033.2.47.21 to 33.2.47.2233.2.47.232
19933.2.47.24/3033.2.47.25 to 33.2.47.2633.2.47.272
20033.2.47.28/3033.2.47.29 to 33.2.47.3033.2.47.312
20133.2.47.32/3033.2.47.33 to 33.2.47.3433.2.47.352
20233.2.47.36/3033.2.47.37 to 33.2.47.3833.2.47.392
20333.2.47.40/3033.2.47.41 to 33.2.47.4233.2.47.432
20433.2.47.44/3033.2.47.45 to 33.2.47.4633.2.47.472
20533.2.47.48/3033.2.47.49 to 33.2.47.5033.2.47.512
20633.2.47.52/3033.2.47.53 to 33.2.47.5433.2.47.552
20733.2.47.56/3033.2.47.57 to 33.2.47.5833.2.47.592
20833.2.47.60/3033.2.47.61 to 33.2.47.6233.2.47.632
20933.2.47.64/3033.2.47.65 to 33.2.47.6633.2.47.672
21033.2.47.68/3033.2.47.69 to 33.2.47.7033.2.47.712
21133.2.47.72/3033.2.47.73 to 33.2.47.7433.2.47.752
21233.2.47.76/3033.2.47.77 to 33.2.47.7833.2.47.792
21333.2.47.80/3033.2.47.81 to 33.2.47.8233.2.47.832
21433.2.47.84/3033.2.47.85 to 33.2.47.8633.2.47.872
21533.2.47.88/3033.2.47.89 to 33.2.47.9033.2.47.912
21633.2.47.92/3033.2.47.93 to 33.2.47.9433.2.47.952
21733.2.47.96/3033.2.47.97 to 33.2.47.9833.2.47.992
21833.2.47.100/3033.2.47.101 to 33.2.47.10233.2.47.1032
21933.2.47.104/3033.2.47.105 to 33.2.47.10633.2.47.1072
22033.2.47.108/3033.2.47.109 to 33.2.47.11033.2.47.1112
22133.2.47.112/3033.2.47.113 to 33.2.47.11433.2.47.1152
22233.2.47.116/3033.2.47.117 to 33.2.47.11833.2.47.1192
22333.2.47.120/3033.2.47.121 to 33.2.47.12233.2.47.1232
22433.2.47.124/3033.2.47.125 to 33.2.47.12633.2.47.1272
22533.2.47.128/3033.2.47.129 to 33.2.47.13033.2.47.1312
22633.2.47.132/3033.2.47.133 to 33.2.47.13433.2.47.1352
22733.2.47.136/3033.2.47.137 to 33.2.47.13833.2.47.1392
22833.2.47.140/3033.2.47.141 to 33.2.47.14233.2.47.1432
22933.2.47.144/3033.2.47.145 to 33.2.47.14633.2.47.1472
23033.2.47.148/3033.2.47.149 to 33.2.47.15033.2.47.1512
23133.2.47.152/3033.2.47.153 to 33.2.47.15433.2.47.1552
23233.2.47.156/3033.2.47.157 to 33.2.47.15833.2.47.1592
23333.2.47.160/3033.2.47.161 to 33.2.47.16233.2.47.1632
23433.2.47.164/3033.2.47.165 to 33.2.47.16633.2.47.1672
23533.2.47.168/3033.2.47.169 to 33.2.47.17033.2.47.1712
23633.2.47.172/3033.2.47.173 to 33.2.47.17433.2.47.1752
23733.2.47.176/3033.2.47.177 to 33.2.47.17833.2.47.1792
23833.2.47.180/3033.2.47.181 to 33.2.47.18233.2.47.1832
23933.2.47.184/3033.2.47.185 to 33.2.47.18633.2.47.1872
24033.2.47.188/3033.2.47.189 to 33.2.47.19033.2.47.1912
24133.2.47.192/3033.2.47.193 to 33.2.47.19433.2.47.1952
24233.2.47.196/3033.2.47.197 to 33.2.47.19833.2.47.1992
24333.2.47.200/3033.2.47.201 to 33.2.47.20233.2.47.2032
24433.2.47.204/3033.2.47.205 to 33.2.47.20633.2.47.2072
24533.2.47.208/3033.2.47.209 to 33.2.47.21033.2.47.2112
24633.2.47.212/3033.2.47.213 to 33.2.47.21433.2.47.2152
24733.2.47.216/3033.2.47.217 to 33.2.47.21833.2.47.2192
24833.2.47.220/3033.2.47.221 to 33.2.47.22233.2.47.2232
24933.2.47.224/3033.2.47.225 to 33.2.47.22633.2.47.2272
25033.2.47.228/3033.2.47.229 to 33.2.47.23033.2.47.2312
25133.2.47.232/3033.2.47.233 to 33.2.47.23433.2.47.2352
25233.2.47.236/3033.2.47.237 to 33.2.47.23833.2.47.2392
25333.2.47.240/3033.2.47.241 to 33.2.47.24233.2.47.2432
25433.2.47.244/3033.2.47.245 to 33.2.47.24633.2.47.2472
25533.2.47.248/3033.2.47.249 to 33.2.47.25033.2.47.2512
25633.2.47.252/3033.2.47.253 to 33.2.47.25433.2.47.2552

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