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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.

Network63.2.76.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
63.2.76.0
Broadcast address
63.2.79.255
First usable
63.2.76.1
Last usable
63.2.79.254
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 3F024C00 · Integer 1057115136 to 1057116159
Reverse DNS zones
76.2.63.in-addr.arpa
77.2.63.in-addr.arpa
78.2.63.in-addr.arpa
79.2.63.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
Address00111111.00000010.01001100.0000000063.2.76.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network00111111.00000010.01001100.0000000063.2.76.0
Broadcast00111111.00000010.01001111.1111111163.2.79.255
Split into smaller subnets/30

63.2.76.0/22 makes 256 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
163.2.76.0/3063.2.76.1 to 63.2.76.263.2.76.32
263.2.76.4/3063.2.76.5 to 63.2.76.663.2.76.72
363.2.76.8/3063.2.76.9 to 63.2.76.1063.2.76.112
463.2.76.12/3063.2.76.13 to 63.2.76.1463.2.76.152
563.2.76.16/3063.2.76.17 to 63.2.76.1863.2.76.192
663.2.76.20/3063.2.76.21 to 63.2.76.2263.2.76.232
763.2.76.24/3063.2.76.25 to 63.2.76.2663.2.76.272
863.2.76.28/3063.2.76.29 to 63.2.76.3063.2.76.312
963.2.76.32/3063.2.76.33 to 63.2.76.3463.2.76.352
1063.2.76.36/3063.2.76.37 to 63.2.76.3863.2.76.392
1163.2.76.40/3063.2.76.41 to 63.2.76.4263.2.76.432
1263.2.76.44/3063.2.76.45 to 63.2.76.4663.2.76.472
1363.2.76.48/3063.2.76.49 to 63.2.76.5063.2.76.512
1463.2.76.52/3063.2.76.53 to 63.2.76.5463.2.76.552
1563.2.76.56/3063.2.76.57 to 63.2.76.5863.2.76.592
1663.2.76.60/3063.2.76.61 to 63.2.76.6263.2.76.632
1763.2.76.64/3063.2.76.65 to 63.2.76.6663.2.76.672
1863.2.76.68/3063.2.76.69 to 63.2.76.7063.2.76.712
1963.2.76.72/3063.2.76.73 to 63.2.76.7463.2.76.752
2063.2.76.76/3063.2.76.77 to 63.2.76.7863.2.76.792
2163.2.76.80/3063.2.76.81 to 63.2.76.8263.2.76.832
2263.2.76.84/3063.2.76.85 to 63.2.76.8663.2.76.872
2363.2.76.88/3063.2.76.89 to 63.2.76.9063.2.76.912
2463.2.76.92/3063.2.76.93 to 63.2.76.9463.2.76.952
2563.2.76.96/3063.2.76.97 to 63.2.76.9863.2.76.992
2663.2.76.100/3063.2.76.101 to 63.2.76.10263.2.76.1032
2763.2.76.104/3063.2.76.105 to 63.2.76.10663.2.76.1072
2863.2.76.108/3063.2.76.109 to 63.2.76.11063.2.76.1112
2963.2.76.112/3063.2.76.113 to 63.2.76.11463.2.76.1152
3063.2.76.116/3063.2.76.117 to 63.2.76.11863.2.76.1192
3163.2.76.120/3063.2.76.121 to 63.2.76.12263.2.76.1232
3263.2.76.124/3063.2.76.125 to 63.2.76.12663.2.76.1272
3363.2.76.128/3063.2.76.129 to 63.2.76.13063.2.76.1312
3463.2.76.132/3063.2.76.133 to 63.2.76.13463.2.76.1352
3563.2.76.136/3063.2.76.137 to 63.2.76.13863.2.76.1392
3663.2.76.140/3063.2.76.141 to 63.2.76.14263.2.76.1432
3763.2.76.144/3063.2.76.145 to 63.2.76.14663.2.76.1472
3863.2.76.148/3063.2.76.149 to 63.2.76.15063.2.76.1512
3963.2.76.152/3063.2.76.153 to 63.2.76.15463.2.76.1552
4063.2.76.156/3063.2.76.157 to 63.2.76.15863.2.76.1592
4163.2.76.160/3063.2.76.161 to 63.2.76.16263.2.76.1632
4263.2.76.164/3063.2.76.165 to 63.2.76.16663.2.76.1672
4363.2.76.168/3063.2.76.169 to 63.2.76.17063.2.76.1712
4463.2.76.172/3063.2.76.173 to 63.2.76.17463.2.76.1752
4563.2.76.176/3063.2.76.177 to 63.2.76.17863.2.76.1792
4663.2.76.180/3063.2.76.181 to 63.2.76.18263.2.76.1832
4763.2.76.184/3063.2.76.185 to 63.2.76.18663.2.76.1872
4863.2.76.188/3063.2.76.189 to 63.2.76.19063.2.76.1912
4963.2.76.192/3063.2.76.193 to 63.2.76.19463.2.76.1952
5063.2.76.196/3063.2.76.197 to 63.2.76.19863.2.76.1992
5163.2.76.200/3063.2.76.201 to 63.2.76.20263.2.76.2032
5263.2.76.204/3063.2.76.205 to 63.2.76.20663.2.76.2072
5363.2.76.208/3063.2.76.209 to 63.2.76.21063.2.76.2112
5463.2.76.212/3063.2.76.213 to 63.2.76.21463.2.76.2152
5563.2.76.216/3063.2.76.217 to 63.2.76.21863.2.76.2192
5663.2.76.220/3063.2.76.221 to 63.2.76.22263.2.76.2232
5763.2.76.224/3063.2.76.225 to 63.2.76.22663.2.76.2272
5863.2.76.228/3063.2.76.229 to 63.2.76.23063.2.76.2312
5963.2.76.232/3063.2.76.233 to 63.2.76.23463.2.76.2352
6063.2.76.236/3063.2.76.237 to 63.2.76.23863.2.76.2392
6163.2.76.240/3063.2.76.241 to 63.2.76.24263.2.76.2432
6263.2.76.244/3063.2.76.245 to 63.2.76.24663.2.76.2472
6363.2.76.248/3063.2.76.249 to 63.2.76.25063.2.76.2512
6463.2.76.252/3063.2.76.253 to 63.2.76.25463.2.76.2552
6563.2.77.0/3063.2.77.1 to 63.2.77.263.2.77.32
6663.2.77.4/3063.2.77.5 to 63.2.77.663.2.77.72
6763.2.77.8/3063.2.77.9 to 63.2.77.1063.2.77.112
6863.2.77.12/3063.2.77.13 to 63.2.77.1463.2.77.152
6963.2.77.16/3063.2.77.17 to 63.2.77.1863.2.77.192
7063.2.77.20/3063.2.77.21 to 63.2.77.2263.2.77.232
7163.2.77.24/3063.2.77.25 to 63.2.77.2663.2.77.272
7263.2.77.28/3063.2.77.29 to 63.2.77.3063.2.77.312
7363.2.77.32/3063.2.77.33 to 63.2.77.3463.2.77.352
7463.2.77.36/3063.2.77.37 to 63.2.77.3863.2.77.392
7563.2.77.40/3063.2.77.41 to 63.2.77.4263.2.77.432
7663.2.77.44/3063.2.77.45 to 63.2.77.4663.2.77.472
7763.2.77.48/3063.2.77.49 to 63.2.77.5063.2.77.512
7863.2.77.52/3063.2.77.53 to 63.2.77.5463.2.77.552
7963.2.77.56/3063.2.77.57 to 63.2.77.5863.2.77.592
8063.2.77.60/3063.2.77.61 to 63.2.77.6263.2.77.632
8163.2.77.64/3063.2.77.65 to 63.2.77.6663.2.77.672
8263.2.77.68/3063.2.77.69 to 63.2.77.7063.2.77.712
8363.2.77.72/3063.2.77.73 to 63.2.77.7463.2.77.752
8463.2.77.76/3063.2.77.77 to 63.2.77.7863.2.77.792
8563.2.77.80/3063.2.77.81 to 63.2.77.8263.2.77.832
8663.2.77.84/3063.2.77.85 to 63.2.77.8663.2.77.872
8763.2.77.88/3063.2.77.89 to 63.2.77.9063.2.77.912
8863.2.77.92/3063.2.77.93 to 63.2.77.9463.2.77.952
8963.2.77.96/3063.2.77.97 to 63.2.77.9863.2.77.992
9063.2.77.100/3063.2.77.101 to 63.2.77.10263.2.77.1032
9163.2.77.104/3063.2.77.105 to 63.2.77.10663.2.77.1072
9263.2.77.108/3063.2.77.109 to 63.2.77.11063.2.77.1112
9363.2.77.112/3063.2.77.113 to 63.2.77.11463.2.77.1152
9463.2.77.116/3063.2.77.117 to 63.2.77.11863.2.77.1192
9563.2.77.120/3063.2.77.121 to 63.2.77.12263.2.77.1232
9663.2.77.124/3063.2.77.125 to 63.2.77.12663.2.77.1272
9763.2.77.128/3063.2.77.129 to 63.2.77.13063.2.77.1312
9863.2.77.132/3063.2.77.133 to 63.2.77.13463.2.77.1352
9963.2.77.136/3063.2.77.137 to 63.2.77.13863.2.77.1392
10063.2.77.140/3063.2.77.141 to 63.2.77.14263.2.77.1432
10163.2.77.144/3063.2.77.145 to 63.2.77.14663.2.77.1472
10263.2.77.148/3063.2.77.149 to 63.2.77.15063.2.77.1512
10363.2.77.152/3063.2.77.153 to 63.2.77.15463.2.77.1552
10463.2.77.156/3063.2.77.157 to 63.2.77.15863.2.77.1592
10563.2.77.160/3063.2.77.161 to 63.2.77.16263.2.77.1632
10663.2.77.164/3063.2.77.165 to 63.2.77.16663.2.77.1672
10763.2.77.168/3063.2.77.169 to 63.2.77.17063.2.77.1712
10863.2.77.172/3063.2.77.173 to 63.2.77.17463.2.77.1752
10963.2.77.176/3063.2.77.177 to 63.2.77.17863.2.77.1792
11063.2.77.180/3063.2.77.181 to 63.2.77.18263.2.77.1832
11163.2.77.184/3063.2.77.185 to 63.2.77.18663.2.77.1872
11263.2.77.188/3063.2.77.189 to 63.2.77.19063.2.77.1912
11363.2.77.192/3063.2.77.193 to 63.2.77.19463.2.77.1952
11463.2.77.196/3063.2.77.197 to 63.2.77.19863.2.77.1992
11563.2.77.200/3063.2.77.201 to 63.2.77.20263.2.77.2032
11663.2.77.204/3063.2.77.205 to 63.2.77.20663.2.77.2072
11763.2.77.208/3063.2.77.209 to 63.2.77.21063.2.77.2112
11863.2.77.212/3063.2.77.213 to 63.2.77.21463.2.77.2152
11963.2.77.216/3063.2.77.217 to 63.2.77.21863.2.77.2192
12063.2.77.220/3063.2.77.221 to 63.2.77.22263.2.77.2232
12163.2.77.224/3063.2.77.225 to 63.2.77.22663.2.77.2272
12263.2.77.228/3063.2.77.229 to 63.2.77.23063.2.77.2312
12363.2.77.232/3063.2.77.233 to 63.2.77.23463.2.77.2352
12463.2.77.236/3063.2.77.237 to 63.2.77.23863.2.77.2392
12563.2.77.240/3063.2.77.241 to 63.2.77.24263.2.77.2432
12663.2.77.244/3063.2.77.245 to 63.2.77.24663.2.77.2472
12763.2.77.248/3063.2.77.249 to 63.2.77.25063.2.77.2512
12863.2.77.252/3063.2.77.253 to 63.2.77.25463.2.77.2552
12963.2.78.0/3063.2.78.1 to 63.2.78.263.2.78.32
13063.2.78.4/3063.2.78.5 to 63.2.78.663.2.78.72
13163.2.78.8/3063.2.78.9 to 63.2.78.1063.2.78.112
13263.2.78.12/3063.2.78.13 to 63.2.78.1463.2.78.152
13363.2.78.16/3063.2.78.17 to 63.2.78.1863.2.78.192
13463.2.78.20/3063.2.78.21 to 63.2.78.2263.2.78.232
13563.2.78.24/3063.2.78.25 to 63.2.78.2663.2.78.272
13663.2.78.28/3063.2.78.29 to 63.2.78.3063.2.78.312
13763.2.78.32/3063.2.78.33 to 63.2.78.3463.2.78.352
13863.2.78.36/3063.2.78.37 to 63.2.78.3863.2.78.392
13963.2.78.40/3063.2.78.41 to 63.2.78.4263.2.78.432
14063.2.78.44/3063.2.78.45 to 63.2.78.4663.2.78.472
14163.2.78.48/3063.2.78.49 to 63.2.78.5063.2.78.512
14263.2.78.52/3063.2.78.53 to 63.2.78.5463.2.78.552
14363.2.78.56/3063.2.78.57 to 63.2.78.5863.2.78.592
14463.2.78.60/3063.2.78.61 to 63.2.78.6263.2.78.632
14563.2.78.64/3063.2.78.65 to 63.2.78.6663.2.78.672
14663.2.78.68/3063.2.78.69 to 63.2.78.7063.2.78.712
14763.2.78.72/3063.2.78.73 to 63.2.78.7463.2.78.752
14863.2.78.76/3063.2.78.77 to 63.2.78.7863.2.78.792
14963.2.78.80/3063.2.78.81 to 63.2.78.8263.2.78.832
15063.2.78.84/3063.2.78.85 to 63.2.78.8663.2.78.872
15163.2.78.88/3063.2.78.89 to 63.2.78.9063.2.78.912
15263.2.78.92/3063.2.78.93 to 63.2.78.9463.2.78.952
15363.2.78.96/3063.2.78.97 to 63.2.78.9863.2.78.992
15463.2.78.100/3063.2.78.101 to 63.2.78.10263.2.78.1032
15563.2.78.104/3063.2.78.105 to 63.2.78.10663.2.78.1072
15663.2.78.108/3063.2.78.109 to 63.2.78.11063.2.78.1112
15763.2.78.112/3063.2.78.113 to 63.2.78.11463.2.78.1152
15863.2.78.116/3063.2.78.117 to 63.2.78.11863.2.78.1192
15963.2.78.120/3063.2.78.121 to 63.2.78.12263.2.78.1232
16063.2.78.124/3063.2.78.125 to 63.2.78.12663.2.78.1272
16163.2.78.128/3063.2.78.129 to 63.2.78.13063.2.78.1312
16263.2.78.132/3063.2.78.133 to 63.2.78.13463.2.78.1352
16363.2.78.136/3063.2.78.137 to 63.2.78.13863.2.78.1392
16463.2.78.140/3063.2.78.141 to 63.2.78.14263.2.78.1432
16563.2.78.144/3063.2.78.145 to 63.2.78.14663.2.78.1472
16663.2.78.148/3063.2.78.149 to 63.2.78.15063.2.78.1512
16763.2.78.152/3063.2.78.153 to 63.2.78.15463.2.78.1552
16863.2.78.156/3063.2.78.157 to 63.2.78.15863.2.78.1592
16963.2.78.160/3063.2.78.161 to 63.2.78.16263.2.78.1632
17063.2.78.164/3063.2.78.165 to 63.2.78.16663.2.78.1672
17163.2.78.168/3063.2.78.169 to 63.2.78.17063.2.78.1712
17263.2.78.172/3063.2.78.173 to 63.2.78.17463.2.78.1752
17363.2.78.176/3063.2.78.177 to 63.2.78.17863.2.78.1792
17463.2.78.180/3063.2.78.181 to 63.2.78.18263.2.78.1832
17563.2.78.184/3063.2.78.185 to 63.2.78.18663.2.78.1872
17663.2.78.188/3063.2.78.189 to 63.2.78.19063.2.78.1912
17763.2.78.192/3063.2.78.193 to 63.2.78.19463.2.78.1952
17863.2.78.196/3063.2.78.197 to 63.2.78.19863.2.78.1992
17963.2.78.200/3063.2.78.201 to 63.2.78.20263.2.78.2032
18063.2.78.204/3063.2.78.205 to 63.2.78.20663.2.78.2072
18163.2.78.208/3063.2.78.209 to 63.2.78.21063.2.78.2112
18263.2.78.212/3063.2.78.213 to 63.2.78.21463.2.78.2152
18363.2.78.216/3063.2.78.217 to 63.2.78.21863.2.78.2192
18463.2.78.220/3063.2.78.221 to 63.2.78.22263.2.78.2232
18563.2.78.224/3063.2.78.225 to 63.2.78.22663.2.78.2272
18663.2.78.228/3063.2.78.229 to 63.2.78.23063.2.78.2312
18763.2.78.232/3063.2.78.233 to 63.2.78.23463.2.78.2352
18863.2.78.236/3063.2.78.237 to 63.2.78.23863.2.78.2392
18963.2.78.240/3063.2.78.241 to 63.2.78.24263.2.78.2432
19063.2.78.244/3063.2.78.245 to 63.2.78.24663.2.78.2472
19163.2.78.248/3063.2.78.249 to 63.2.78.25063.2.78.2512
19263.2.78.252/3063.2.78.253 to 63.2.78.25463.2.78.2552
19363.2.79.0/3063.2.79.1 to 63.2.79.263.2.79.32
19463.2.79.4/3063.2.79.5 to 63.2.79.663.2.79.72
19563.2.79.8/3063.2.79.9 to 63.2.79.1063.2.79.112
19663.2.79.12/3063.2.79.13 to 63.2.79.1463.2.79.152
19763.2.79.16/3063.2.79.17 to 63.2.79.1863.2.79.192
19863.2.79.20/3063.2.79.21 to 63.2.79.2263.2.79.232
19963.2.79.24/3063.2.79.25 to 63.2.79.2663.2.79.272
20063.2.79.28/3063.2.79.29 to 63.2.79.3063.2.79.312
20163.2.79.32/3063.2.79.33 to 63.2.79.3463.2.79.352
20263.2.79.36/3063.2.79.37 to 63.2.79.3863.2.79.392
20363.2.79.40/3063.2.79.41 to 63.2.79.4263.2.79.432
20463.2.79.44/3063.2.79.45 to 63.2.79.4663.2.79.472
20563.2.79.48/3063.2.79.49 to 63.2.79.5063.2.79.512
20663.2.79.52/3063.2.79.53 to 63.2.79.5463.2.79.552
20763.2.79.56/3063.2.79.57 to 63.2.79.5863.2.79.592
20863.2.79.60/3063.2.79.61 to 63.2.79.6263.2.79.632
20963.2.79.64/3063.2.79.65 to 63.2.79.6663.2.79.672
21063.2.79.68/3063.2.79.69 to 63.2.79.7063.2.79.712
21163.2.79.72/3063.2.79.73 to 63.2.79.7463.2.79.752
21263.2.79.76/3063.2.79.77 to 63.2.79.7863.2.79.792
21363.2.79.80/3063.2.79.81 to 63.2.79.8263.2.79.832
21463.2.79.84/3063.2.79.85 to 63.2.79.8663.2.79.872
21563.2.79.88/3063.2.79.89 to 63.2.79.9063.2.79.912
21663.2.79.92/3063.2.79.93 to 63.2.79.9463.2.79.952
21763.2.79.96/3063.2.79.97 to 63.2.79.9863.2.79.992
21863.2.79.100/3063.2.79.101 to 63.2.79.10263.2.79.1032
21963.2.79.104/3063.2.79.105 to 63.2.79.10663.2.79.1072
22063.2.79.108/3063.2.79.109 to 63.2.79.11063.2.79.1112
22163.2.79.112/3063.2.79.113 to 63.2.79.11463.2.79.1152
22263.2.79.116/3063.2.79.117 to 63.2.79.11863.2.79.1192
22363.2.79.120/3063.2.79.121 to 63.2.79.12263.2.79.1232
22463.2.79.124/3063.2.79.125 to 63.2.79.12663.2.79.1272
22563.2.79.128/3063.2.79.129 to 63.2.79.13063.2.79.1312
22663.2.79.132/3063.2.79.133 to 63.2.79.13463.2.79.1352
22763.2.79.136/3063.2.79.137 to 63.2.79.13863.2.79.1392
22863.2.79.140/3063.2.79.141 to 63.2.79.14263.2.79.1432
22963.2.79.144/3063.2.79.145 to 63.2.79.14663.2.79.1472
23063.2.79.148/3063.2.79.149 to 63.2.79.15063.2.79.1512
23163.2.79.152/3063.2.79.153 to 63.2.79.15463.2.79.1552
23263.2.79.156/3063.2.79.157 to 63.2.79.15863.2.79.1592
23363.2.79.160/3063.2.79.161 to 63.2.79.16263.2.79.1632
23463.2.79.164/3063.2.79.165 to 63.2.79.16663.2.79.1672
23563.2.79.168/3063.2.79.169 to 63.2.79.17063.2.79.1712
23663.2.79.172/3063.2.79.173 to 63.2.79.17463.2.79.1752
23763.2.79.176/3063.2.79.177 to 63.2.79.17863.2.79.1792
23863.2.79.180/3063.2.79.181 to 63.2.79.18263.2.79.1832
23963.2.79.184/3063.2.79.185 to 63.2.79.18663.2.79.1872
24063.2.79.188/3063.2.79.189 to 63.2.79.19063.2.79.1912
24163.2.79.192/3063.2.79.193 to 63.2.79.19463.2.79.1952
24263.2.79.196/3063.2.79.197 to 63.2.79.19863.2.79.1992
24363.2.79.200/3063.2.79.201 to 63.2.79.20263.2.79.2032
24463.2.79.204/3063.2.79.205 to 63.2.79.20663.2.79.2072
24563.2.79.208/3063.2.79.209 to 63.2.79.21063.2.79.2112
24663.2.79.212/3063.2.79.213 to 63.2.79.21463.2.79.2152
24763.2.79.216/3063.2.79.217 to 63.2.79.21863.2.79.2192
24863.2.79.220/3063.2.79.221 to 63.2.79.22263.2.79.2232
24963.2.79.224/3063.2.79.225 to 63.2.79.22663.2.79.2272
25063.2.79.228/3063.2.79.229 to 63.2.79.23063.2.79.2312
25163.2.79.232/3063.2.79.233 to 63.2.79.23463.2.79.2352
25263.2.79.236/3063.2.79.237 to 63.2.79.23863.2.79.2392
25363.2.79.240/3063.2.79.241 to 63.2.79.24263.2.79.2432
25463.2.79.244/3063.2.79.245 to 63.2.79.24663.2.79.2472
25563.2.79.248/3063.2.79.249 to 63.2.79.25063.2.79.2512
25663.2.79.252/3063.2.79.253 to 63.2.79.25463.2.79.2552

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