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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.

Network33.78.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
33.78.0.0
Broadcast address
33.78.255.255
First usable
33.78.0.1
Last usable
33.78.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 214E0000 · Integer 558759936 to 558825471
Reverse DNS zone
78.33.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00100001.01001110..00000000.0000000033.78.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network00100001.01001110..00000000.0000000033.78.0.0
Broadcast00100001.01001110..11111111.1111111133.78.255.255
Split into smaller subnets/28

33.78.0.0/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
133.78.0.0/2833.78.0.1 to 33.78.0.1433.78.0.1514
233.78.0.16/2833.78.0.17 to 33.78.0.3033.78.0.3114
333.78.0.32/2833.78.0.33 to 33.78.0.4633.78.0.4714
433.78.0.48/2833.78.0.49 to 33.78.0.6233.78.0.6314
533.78.0.64/2833.78.0.65 to 33.78.0.7833.78.0.7914
633.78.0.80/2833.78.0.81 to 33.78.0.9433.78.0.9514
733.78.0.96/2833.78.0.97 to 33.78.0.11033.78.0.11114
833.78.0.112/2833.78.0.113 to 33.78.0.12633.78.0.12714
933.78.0.128/2833.78.0.129 to 33.78.0.14233.78.0.14314
1033.78.0.144/2833.78.0.145 to 33.78.0.15833.78.0.15914
1133.78.0.160/2833.78.0.161 to 33.78.0.17433.78.0.17514
1233.78.0.176/2833.78.0.177 to 33.78.0.19033.78.0.19114
1333.78.0.192/2833.78.0.193 to 33.78.0.20633.78.0.20714
1433.78.0.208/2833.78.0.209 to 33.78.0.22233.78.0.22314
1533.78.0.224/2833.78.0.225 to 33.78.0.23833.78.0.23914
1633.78.0.240/2833.78.0.241 to 33.78.0.25433.78.0.25514
1733.78.1.0/2833.78.1.1 to 33.78.1.1433.78.1.1514
1833.78.1.16/2833.78.1.17 to 33.78.1.3033.78.1.3114
1933.78.1.32/2833.78.1.33 to 33.78.1.4633.78.1.4714
2033.78.1.48/2833.78.1.49 to 33.78.1.6233.78.1.6314
2133.78.1.64/2833.78.1.65 to 33.78.1.7833.78.1.7914
2233.78.1.80/2833.78.1.81 to 33.78.1.9433.78.1.9514
2333.78.1.96/2833.78.1.97 to 33.78.1.11033.78.1.11114
2433.78.1.112/2833.78.1.113 to 33.78.1.12633.78.1.12714
2533.78.1.128/2833.78.1.129 to 33.78.1.14233.78.1.14314
2633.78.1.144/2833.78.1.145 to 33.78.1.15833.78.1.15914
2733.78.1.160/2833.78.1.161 to 33.78.1.17433.78.1.17514
2833.78.1.176/2833.78.1.177 to 33.78.1.19033.78.1.19114
2933.78.1.192/2833.78.1.193 to 33.78.1.20633.78.1.20714
3033.78.1.208/2833.78.1.209 to 33.78.1.22233.78.1.22314
3133.78.1.224/2833.78.1.225 to 33.78.1.23833.78.1.23914
3233.78.1.240/2833.78.1.241 to 33.78.1.25433.78.1.25514
3333.78.2.0/2833.78.2.1 to 33.78.2.1433.78.2.1514
3433.78.2.16/2833.78.2.17 to 33.78.2.3033.78.2.3114
3533.78.2.32/2833.78.2.33 to 33.78.2.4633.78.2.4714
3633.78.2.48/2833.78.2.49 to 33.78.2.6233.78.2.6314
3733.78.2.64/2833.78.2.65 to 33.78.2.7833.78.2.7914
3833.78.2.80/2833.78.2.81 to 33.78.2.9433.78.2.9514
3933.78.2.96/2833.78.2.97 to 33.78.2.11033.78.2.11114
4033.78.2.112/2833.78.2.113 to 33.78.2.12633.78.2.12714
4133.78.2.128/2833.78.2.129 to 33.78.2.14233.78.2.14314
4233.78.2.144/2833.78.2.145 to 33.78.2.15833.78.2.15914
4333.78.2.160/2833.78.2.161 to 33.78.2.17433.78.2.17514
4433.78.2.176/2833.78.2.177 to 33.78.2.19033.78.2.19114
4533.78.2.192/2833.78.2.193 to 33.78.2.20633.78.2.20714
4633.78.2.208/2833.78.2.209 to 33.78.2.22233.78.2.22314
4733.78.2.224/2833.78.2.225 to 33.78.2.23833.78.2.23914
4833.78.2.240/2833.78.2.241 to 33.78.2.25433.78.2.25514
4933.78.3.0/2833.78.3.1 to 33.78.3.1433.78.3.1514
5033.78.3.16/2833.78.3.17 to 33.78.3.3033.78.3.3114
5133.78.3.32/2833.78.3.33 to 33.78.3.4633.78.3.4714
5233.78.3.48/2833.78.3.49 to 33.78.3.6233.78.3.6314
5333.78.3.64/2833.78.3.65 to 33.78.3.7833.78.3.7914
5433.78.3.80/2833.78.3.81 to 33.78.3.9433.78.3.9514
5533.78.3.96/2833.78.3.97 to 33.78.3.11033.78.3.11114
5633.78.3.112/2833.78.3.113 to 33.78.3.12633.78.3.12714
5733.78.3.128/2833.78.3.129 to 33.78.3.14233.78.3.14314
5833.78.3.144/2833.78.3.145 to 33.78.3.15833.78.3.15914
5933.78.3.160/2833.78.3.161 to 33.78.3.17433.78.3.17514
6033.78.3.176/2833.78.3.177 to 33.78.3.19033.78.3.19114
6133.78.3.192/2833.78.3.193 to 33.78.3.20633.78.3.20714
6233.78.3.208/2833.78.3.209 to 33.78.3.22233.78.3.22314
6333.78.3.224/2833.78.3.225 to 33.78.3.23833.78.3.23914
6433.78.3.240/2833.78.3.241 to 33.78.3.25433.78.3.25514
6533.78.4.0/2833.78.4.1 to 33.78.4.1433.78.4.1514
6633.78.4.16/2833.78.4.17 to 33.78.4.3033.78.4.3114
6733.78.4.32/2833.78.4.33 to 33.78.4.4633.78.4.4714
6833.78.4.48/2833.78.4.49 to 33.78.4.6233.78.4.6314
6933.78.4.64/2833.78.4.65 to 33.78.4.7833.78.4.7914
7033.78.4.80/2833.78.4.81 to 33.78.4.9433.78.4.9514
7133.78.4.96/2833.78.4.97 to 33.78.4.11033.78.4.11114
7233.78.4.112/2833.78.4.113 to 33.78.4.12633.78.4.12714
7333.78.4.128/2833.78.4.129 to 33.78.4.14233.78.4.14314
7433.78.4.144/2833.78.4.145 to 33.78.4.15833.78.4.15914
7533.78.4.160/2833.78.4.161 to 33.78.4.17433.78.4.17514
7633.78.4.176/2833.78.4.177 to 33.78.4.19033.78.4.19114
7733.78.4.192/2833.78.4.193 to 33.78.4.20633.78.4.20714
7833.78.4.208/2833.78.4.209 to 33.78.4.22233.78.4.22314
7933.78.4.224/2833.78.4.225 to 33.78.4.23833.78.4.23914
8033.78.4.240/2833.78.4.241 to 33.78.4.25433.78.4.25514
8133.78.5.0/2833.78.5.1 to 33.78.5.1433.78.5.1514
8233.78.5.16/2833.78.5.17 to 33.78.5.3033.78.5.3114
8333.78.5.32/2833.78.5.33 to 33.78.5.4633.78.5.4714
8433.78.5.48/2833.78.5.49 to 33.78.5.6233.78.5.6314
8533.78.5.64/2833.78.5.65 to 33.78.5.7833.78.5.7914
8633.78.5.80/2833.78.5.81 to 33.78.5.9433.78.5.9514
8733.78.5.96/2833.78.5.97 to 33.78.5.11033.78.5.11114
8833.78.5.112/2833.78.5.113 to 33.78.5.12633.78.5.12714
8933.78.5.128/2833.78.5.129 to 33.78.5.14233.78.5.14314
9033.78.5.144/2833.78.5.145 to 33.78.5.15833.78.5.15914
9133.78.5.160/2833.78.5.161 to 33.78.5.17433.78.5.17514
9233.78.5.176/2833.78.5.177 to 33.78.5.19033.78.5.19114
9333.78.5.192/2833.78.5.193 to 33.78.5.20633.78.5.20714
9433.78.5.208/2833.78.5.209 to 33.78.5.22233.78.5.22314
9533.78.5.224/2833.78.5.225 to 33.78.5.23833.78.5.23914
9633.78.5.240/2833.78.5.241 to 33.78.5.25433.78.5.25514
9733.78.6.0/2833.78.6.1 to 33.78.6.1433.78.6.1514
9833.78.6.16/2833.78.6.17 to 33.78.6.3033.78.6.3114
9933.78.6.32/2833.78.6.33 to 33.78.6.4633.78.6.4714
10033.78.6.48/2833.78.6.49 to 33.78.6.6233.78.6.6314
10133.78.6.64/2833.78.6.65 to 33.78.6.7833.78.6.7914
10233.78.6.80/2833.78.6.81 to 33.78.6.9433.78.6.9514
10333.78.6.96/2833.78.6.97 to 33.78.6.11033.78.6.11114
10433.78.6.112/2833.78.6.113 to 33.78.6.12633.78.6.12714
10533.78.6.128/2833.78.6.129 to 33.78.6.14233.78.6.14314
10633.78.6.144/2833.78.6.145 to 33.78.6.15833.78.6.15914
10733.78.6.160/2833.78.6.161 to 33.78.6.17433.78.6.17514
10833.78.6.176/2833.78.6.177 to 33.78.6.19033.78.6.19114
10933.78.6.192/2833.78.6.193 to 33.78.6.20633.78.6.20714
11033.78.6.208/2833.78.6.209 to 33.78.6.22233.78.6.22314
11133.78.6.224/2833.78.6.225 to 33.78.6.23833.78.6.23914
11233.78.6.240/2833.78.6.241 to 33.78.6.25433.78.6.25514
11333.78.7.0/2833.78.7.1 to 33.78.7.1433.78.7.1514
11433.78.7.16/2833.78.7.17 to 33.78.7.3033.78.7.3114
11533.78.7.32/2833.78.7.33 to 33.78.7.4633.78.7.4714
11633.78.7.48/2833.78.7.49 to 33.78.7.6233.78.7.6314
11733.78.7.64/2833.78.7.65 to 33.78.7.7833.78.7.7914
11833.78.7.80/2833.78.7.81 to 33.78.7.9433.78.7.9514
11933.78.7.96/2833.78.7.97 to 33.78.7.11033.78.7.11114
12033.78.7.112/2833.78.7.113 to 33.78.7.12633.78.7.12714
12133.78.7.128/2833.78.7.129 to 33.78.7.14233.78.7.14314
12233.78.7.144/2833.78.7.145 to 33.78.7.15833.78.7.15914
12333.78.7.160/2833.78.7.161 to 33.78.7.17433.78.7.17514
12433.78.7.176/2833.78.7.177 to 33.78.7.19033.78.7.19114
12533.78.7.192/2833.78.7.193 to 33.78.7.20633.78.7.20714
12633.78.7.208/2833.78.7.209 to 33.78.7.22233.78.7.22314
12733.78.7.224/2833.78.7.225 to 33.78.7.23833.78.7.23914
12833.78.7.240/2833.78.7.241 to 33.78.7.25433.78.7.25514
12933.78.8.0/2833.78.8.1 to 33.78.8.1433.78.8.1514
13033.78.8.16/2833.78.8.17 to 33.78.8.3033.78.8.3114
13133.78.8.32/2833.78.8.33 to 33.78.8.4633.78.8.4714
13233.78.8.48/2833.78.8.49 to 33.78.8.6233.78.8.6314
13333.78.8.64/2833.78.8.65 to 33.78.8.7833.78.8.7914
13433.78.8.80/2833.78.8.81 to 33.78.8.9433.78.8.9514
13533.78.8.96/2833.78.8.97 to 33.78.8.11033.78.8.11114
13633.78.8.112/2833.78.8.113 to 33.78.8.12633.78.8.12714
13733.78.8.128/2833.78.8.129 to 33.78.8.14233.78.8.14314
13833.78.8.144/2833.78.8.145 to 33.78.8.15833.78.8.15914
13933.78.8.160/2833.78.8.161 to 33.78.8.17433.78.8.17514
14033.78.8.176/2833.78.8.177 to 33.78.8.19033.78.8.19114
14133.78.8.192/2833.78.8.193 to 33.78.8.20633.78.8.20714
14233.78.8.208/2833.78.8.209 to 33.78.8.22233.78.8.22314
14333.78.8.224/2833.78.8.225 to 33.78.8.23833.78.8.23914
14433.78.8.240/2833.78.8.241 to 33.78.8.25433.78.8.25514
14533.78.9.0/2833.78.9.1 to 33.78.9.1433.78.9.1514
14633.78.9.16/2833.78.9.17 to 33.78.9.3033.78.9.3114
14733.78.9.32/2833.78.9.33 to 33.78.9.4633.78.9.4714
14833.78.9.48/2833.78.9.49 to 33.78.9.6233.78.9.6314
14933.78.9.64/2833.78.9.65 to 33.78.9.7833.78.9.7914
15033.78.9.80/2833.78.9.81 to 33.78.9.9433.78.9.9514
15133.78.9.96/2833.78.9.97 to 33.78.9.11033.78.9.11114
15233.78.9.112/2833.78.9.113 to 33.78.9.12633.78.9.12714
15333.78.9.128/2833.78.9.129 to 33.78.9.14233.78.9.14314
15433.78.9.144/2833.78.9.145 to 33.78.9.15833.78.9.15914
15533.78.9.160/2833.78.9.161 to 33.78.9.17433.78.9.17514
15633.78.9.176/2833.78.9.177 to 33.78.9.19033.78.9.19114
15733.78.9.192/2833.78.9.193 to 33.78.9.20633.78.9.20714
15833.78.9.208/2833.78.9.209 to 33.78.9.22233.78.9.22314
15933.78.9.224/2833.78.9.225 to 33.78.9.23833.78.9.23914
16033.78.9.240/2833.78.9.241 to 33.78.9.25433.78.9.25514
16133.78.10.0/2833.78.10.1 to 33.78.10.1433.78.10.1514
16233.78.10.16/2833.78.10.17 to 33.78.10.3033.78.10.3114
16333.78.10.32/2833.78.10.33 to 33.78.10.4633.78.10.4714
16433.78.10.48/2833.78.10.49 to 33.78.10.6233.78.10.6314
16533.78.10.64/2833.78.10.65 to 33.78.10.7833.78.10.7914
16633.78.10.80/2833.78.10.81 to 33.78.10.9433.78.10.9514
16733.78.10.96/2833.78.10.97 to 33.78.10.11033.78.10.11114
16833.78.10.112/2833.78.10.113 to 33.78.10.12633.78.10.12714
16933.78.10.128/2833.78.10.129 to 33.78.10.14233.78.10.14314
17033.78.10.144/2833.78.10.145 to 33.78.10.15833.78.10.15914
17133.78.10.160/2833.78.10.161 to 33.78.10.17433.78.10.17514
17233.78.10.176/2833.78.10.177 to 33.78.10.19033.78.10.19114
17333.78.10.192/2833.78.10.193 to 33.78.10.20633.78.10.20714
17433.78.10.208/2833.78.10.209 to 33.78.10.22233.78.10.22314
17533.78.10.224/2833.78.10.225 to 33.78.10.23833.78.10.23914
17633.78.10.240/2833.78.10.241 to 33.78.10.25433.78.10.25514
17733.78.11.0/2833.78.11.1 to 33.78.11.1433.78.11.1514
17833.78.11.16/2833.78.11.17 to 33.78.11.3033.78.11.3114
17933.78.11.32/2833.78.11.33 to 33.78.11.4633.78.11.4714
18033.78.11.48/2833.78.11.49 to 33.78.11.6233.78.11.6314
18133.78.11.64/2833.78.11.65 to 33.78.11.7833.78.11.7914
18233.78.11.80/2833.78.11.81 to 33.78.11.9433.78.11.9514
18333.78.11.96/2833.78.11.97 to 33.78.11.11033.78.11.11114
18433.78.11.112/2833.78.11.113 to 33.78.11.12633.78.11.12714
18533.78.11.128/2833.78.11.129 to 33.78.11.14233.78.11.14314
18633.78.11.144/2833.78.11.145 to 33.78.11.15833.78.11.15914
18733.78.11.160/2833.78.11.161 to 33.78.11.17433.78.11.17514
18833.78.11.176/2833.78.11.177 to 33.78.11.19033.78.11.19114
18933.78.11.192/2833.78.11.193 to 33.78.11.20633.78.11.20714
19033.78.11.208/2833.78.11.209 to 33.78.11.22233.78.11.22314
19133.78.11.224/2833.78.11.225 to 33.78.11.23833.78.11.23914
19233.78.11.240/2833.78.11.241 to 33.78.11.25433.78.11.25514
19333.78.12.0/2833.78.12.1 to 33.78.12.1433.78.12.1514
19433.78.12.16/2833.78.12.17 to 33.78.12.3033.78.12.3114
19533.78.12.32/2833.78.12.33 to 33.78.12.4633.78.12.4714
19633.78.12.48/2833.78.12.49 to 33.78.12.6233.78.12.6314
19733.78.12.64/2833.78.12.65 to 33.78.12.7833.78.12.7914
19833.78.12.80/2833.78.12.81 to 33.78.12.9433.78.12.9514
19933.78.12.96/2833.78.12.97 to 33.78.12.11033.78.12.11114
20033.78.12.112/2833.78.12.113 to 33.78.12.12633.78.12.12714
20133.78.12.128/2833.78.12.129 to 33.78.12.14233.78.12.14314
20233.78.12.144/2833.78.12.145 to 33.78.12.15833.78.12.15914
20333.78.12.160/2833.78.12.161 to 33.78.12.17433.78.12.17514
20433.78.12.176/2833.78.12.177 to 33.78.12.19033.78.12.19114
20533.78.12.192/2833.78.12.193 to 33.78.12.20633.78.12.20714
20633.78.12.208/2833.78.12.209 to 33.78.12.22233.78.12.22314
20733.78.12.224/2833.78.12.225 to 33.78.12.23833.78.12.23914
20833.78.12.240/2833.78.12.241 to 33.78.12.25433.78.12.25514
20933.78.13.0/2833.78.13.1 to 33.78.13.1433.78.13.1514
21033.78.13.16/2833.78.13.17 to 33.78.13.3033.78.13.3114
21133.78.13.32/2833.78.13.33 to 33.78.13.4633.78.13.4714
21233.78.13.48/2833.78.13.49 to 33.78.13.6233.78.13.6314
21333.78.13.64/2833.78.13.65 to 33.78.13.7833.78.13.7914
21433.78.13.80/2833.78.13.81 to 33.78.13.9433.78.13.9514
21533.78.13.96/2833.78.13.97 to 33.78.13.11033.78.13.11114
21633.78.13.112/2833.78.13.113 to 33.78.13.12633.78.13.12714
21733.78.13.128/2833.78.13.129 to 33.78.13.14233.78.13.14314
21833.78.13.144/2833.78.13.145 to 33.78.13.15833.78.13.15914
21933.78.13.160/2833.78.13.161 to 33.78.13.17433.78.13.17514
22033.78.13.176/2833.78.13.177 to 33.78.13.19033.78.13.19114
22133.78.13.192/2833.78.13.193 to 33.78.13.20633.78.13.20714
22233.78.13.208/2833.78.13.209 to 33.78.13.22233.78.13.22314
22333.78.13.224/2833.78.13.225 to 33.78.13.23833.78.13.23914
22433.78.13.240/2833.78.13.241 to 33.78.13.25433.78.13.25514
22533.78.14.0/2833.78.14.1 to 33.78.14.1433.78.14.1514
22633.78.14.16/2833.78.14.17 to 33.78.14.3033.78.14.3114
22733.78.14.32/2833.78.14.33 to 33.78.14.4633.78.14.4714
22833.78.14.48/2833.78.14.49 to 33.78.14.6233.78.14.6314
22933.78.14.64/2833.78.14.65 to 33.78.14.7833.78.14.7914
23033.78.14.80/2833.78.14.81 to 33.78.14.9433.78.14.9514
23133.78.14.96/2833.78.14.97 to 33.78.14.11033.78.14.11114
23233.78.14.112/2833.78.14.113 to 33.78.14.12633.78.14.12714
23333.78.14.128/2833.78.14.129 to 33.78.14.14233.78.14.14314
23433.78.14.144/2833.78.14.145 to 33.78.14.15833.78.14.15914
23533.78.14.160/2833.78.14.161 to 33.78.14.17433.78.14.17514
23633.78.14.176/2833.78.14.177 to 33.78.14.19033.78.14.19114
23733.78.14.192/2833.78.14.193 to 33.78.14.20633.78.14.20714
23833.78.14.208/2833.78.14.209 to 33.78.14.22233.78.14.22314
23933.78.14.224/2833.78.14.225 to 33.78.14.23833.78.14.23914
24033.78.14.240/2833.78.14.241 to 33.78.14.25433.78.14.25514
24133.78.15.0/2833.78.15.1 to 33.78.15.1433.78.15.1514
24233.78.15.16/2833.78.15.17 to 33.78.15.3033.78.15.3114
24333.78.15.32/2833.78.15.33 to 33.78.15.4633.78.15.4714
24433.78.15.48/2833.78.15.49 to 33.78.15.6233.78.15.6314
24533.78.15.64/2833.78.15.65 to 33.78.15.7833.78.15.7914
24633.78.15.80/2833.78.15.81 to 33.78.15.9433.78.15.9514
24733.78.15.96/2833.78.15.97 to 33.78.15.11033.78.15.11114
24833.78.15.112/2833.78.15.113 to 33.78.15.12633.78.15.12714
24933.78.15.128/2833.78.15.129 to 33.78.15.14233.78.15.14314
25033.78.15.144/2833.78.15.145 to 33.78.15.15833.78.15.15914
25133.78.15.160/2833.78.15.161 to 33.78.15.17433.78.15.17514
25233.78.15.176/2833.78.15.177 to 33.78.15.19033.78.15.19114
25333.78.15.192/2833.78.15.193 to 33.78.15.20633.78.15.20714
25433.78.15.208/2833.78.15.209 to 33.78.15.22233.78.15.22314
25533.78.15.224/2833.78.15.225 to 33.78.15.23833.78.15.23914
25633.78.15.240/2833.78.15.241 to 33.78.15.25433.78.15.25514

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