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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.

Network43.3.76.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
43.3.76.0
Broadcast address
43.3.79.255
First usable
43.3.76.1
Last usable
43.3.79.254
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 2B034C00 · Integer 721636352 to 721637375
Reverse DNS zones
76.3.43.in-addr.arpa
77.3.43.in-addr.arpa
78.3.43.in-addr.arpa
79.3.43.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
Address00101011.00000011.01001100.0000000043.3.76.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network00101011.00000011.01001100.0000000043.3.76.0
Broadcast00101011.00000011.01001111.1111111143.3.79.255
Split into smaller subnets/30

43.3.76.0/22 makes 256 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
143.3.76.0/3043.3.76.1 to 43.3.76.243.3.76.32
243.3.76.4/3043.3.76.5 to 43.3.76.643.3.76.72
343.3.76.8/3043.3.76.9 to 43.3.76.1043.3.76.112
443.3.76.12/3043.3.76.13 to 43.3.76.1443.3.76.152
543.3.76.16/3043.3.76.17 to 43.3.76.1843.3.76.192
643.3.76.20/3043.3.76.21 to 43.3.76.2243.3.76.232
743.3.76.24/3043.3.76.25 to 43.3.76.2643.3.76.272
843.3.76.28/3043.3.76.29 to 43.3.76.3043.3.76.312
943.3.76.32/3043.3.76.33 to 43.3.76.3443.3.76.352
1043.3.76.36/3043.3.76.37 to 43.3.76.3843.3.76.392
1143.3.76.40/3043.3.76.41 to 43.3.76.4243.3.76.432
1243.3.76.44/3043.3.76.45 to 43.3.76.4643.3.76.472
1343.3.76.48/3043.3.76.49 to 43.3.76.5043.3.76.512
1443.3.76.52/3043.3.76.53 to 43.3.76.5443.3.76.552
1543.3.76.56/3043.3.76.57 to 43.3.76.5843.3.76.592
1643.3.76.60/3043.3.76.61 to 43.3.76.6243.3.76.632
1743.3.76.64/3043.3.76.65 to 43.3.76.6643.3.76.672
1843.3.76.68/3043.3.76.69 to 43.3.76.7043.3.76.712
1943.3.76.72/3043.3.76.73 to 43.3.76.7443.3.76.752
2043.3.76.76/3043.3.76.77 to 43.3.76.7843.3.76.792
2143.3.76.80/3043.3.76.81 to 43.3.76.8243.3.76.832
2243.3.76.84/3043.3.76.85 to 43.3.76.8643.3.76.872
2343.3.76.88/3043.3.76.89 to 43.3.76.9043.3.76.912
2443.3.76.92/3043.3.76.93 to 43.3.76.9443.3.76.952
2543.3.76.96/3043.3.76.97 to 43.3.76.9843.3.76.992
2643.3.76.100/3043.3.76.101 to 43.3.76.10243.3.76.1032
2743.3.76.104/3043.3.76.105 to 43.3.76.10643.3.76.1072
2843.3.76.108/3043.3.76.109 to 43.3.76.11043.3.76.1112
2943.3.76.112/3043.3.76.113 to 43.3.76.11443.3.76.1152
3043.3.76.116/3043.3.76.117 to 43.3.76.11843.3.76.1192
3143.3.76.120/3043.3.76.121 to 43.3.76.12243.3.76.1232
3243.3.76.124/3043.3.76.125 to 43.3.76.12643.3.76.1272
3343.3.76.128/3043.3.76.129 to 43.3.76.13043.3.76.1312
3443.3.76.132/3043.3.76.133 to 43.3.76.13443.3.76.1352
3543.3.76.136/3043.3.76.137 to 43.3.76.13843.3.76.1392
3643.3.76.140/3043.3.76.141 to 43.3.76.14243.3.76.1432
3743.3.76.144/3043.3.76.145 to 43.3.76.14643.3.76.1472
3843.3.76.148/3043.3.76.149 to 43.3.76.15043.3.76.1512
3943.3.76.152/3043.3.76.153 to 43.3.76.15443.3.76.1552
4043.3.76.156/3043.3.76.157 to 43.3.76.15843.3.76.1592
4143.3.76.160/3043.3.76.161 to 43.3.76.16243.3.76.1632
4243.3.76.164/3043.3.76.165 to 43.3.76.16643.3.76.1672
4343.3.76.168/3043.3.76.169 to 43.3.76.17043.3.76.1712
4443.3.76.172/3043.3.76.173 to 43.3.76.17443.3.76.1752
4543.3.76.176/3043.3.76.177 to 43.3.76.17843.3.76.1792
4643.3.76.180/3043.3.76.181 to 43.3.76.18243.3.76.1832
4743.3.76.184/3043.3.76.185 to 43.3.76.18643.3.76.1872
4843.3.76.188/3043.3.76.189 to 43.3.76.19043.3.76.1912
4943.3.76.192/3043.3.76.193 to 43.3.76.19443.3.76.1952
5043.3.76.196/3043.3.76.197 to 43.3.76.19843.3.76.1992
5143.3.76.200/3043.3.76.201 to 43.3.76.20243.3.76.2032
5243.3.76.204/3043.3.76.205 to 43.3.76.20643.3.76.2072
5343.3.76.208/3043.3.76.209 to 43.3.76.21043.3.76.2112
5443.3.76.212/3043.3.76.213 to 43.3.76.21443.3.76.2152
5543.3.76.216/3043.3.76.217 to 43.3.76.21843.3.76.2192
5643.3.76.220/3043.3.76.221 to 43.3.76.22243.3.76.2232
5743.3.76.224/3043.3.76.225 to 43.3.76.22643.3.76.2272
5843.3.76.228/3043.3.76.229 to 43.3.76.23043.3.76.2312
5943.3.76.232/3043.3.76.233 to 43.3.76.23443.3.76.2352
6043.3.76.236/3043.3.76.237 to 43.3.76.23843.3.76.2392
6143.3.76.240/3043.3.76.241 to 43.3.76.24243.3.76.2432
6243.3.76.244/3043.3.76.245 to 43.3.76.24643.3.76.2472
6343.3.76.248/3043.3.76.249 to 43.3.76.25043.3.76.2512
6443.3.76.252/3043.3.76.253 to 43.3.76.25443.3.76.2552
6543.3.77.0/3043.3.77.1 to 43.3.77.243.3.77.32
6643.3.77.4/3043.3.77.5 to 43.3.77.643.3.77.72
6743.3.77.8/3043.3.77.9 to 43.3.77.1043.3.77.112
6843.3.77.12/3043.3.77.13 to 43.3.77.1443.3.77.152
6943.3.77.16/3043.3.77.17 to 43.3.77.1843.3.77.192
7043.3.77.20/3043.3.77.21 to 43.3.77.2243.3.77.232
7143.3.77.24/3043.3.77.25 to 43.3.77.2643.3.77.272
7243.3.77.28/3043.3.77.29 to 43.3.77.3043.3.77.312
7343.3.77.32/3043.3.77.33 to 43.3.77.3443.3.77.352
7443.3.77.36/3043.3.77.37 to 43.3.77.3843.3.77.392
7543.3.77.40/3043.3.77.41 to 43.3.77.4243.3.77.432
7643.3.77.44/3043.3.77.45 to 43.3.77.4643.3.77.472
7743.3.77.48/3043.3.77.49 to 43.3.77.5043.3.77.512
7843.3.77.52/3043.3.77.53 to 43.3.77.5443.3.77.552
7943.3.77.56/3043.3.77.57 to 43.3.77.5843.3.77.592
8043.3.77.60/3043.3.77.61 to 43.3.77.6243.3.77.632
8143.3.77.64/3043.3.77.65 to 43.3.77.6643.3.77.672
8243.3.77.68/3043.3.77.69 to 43.3.77.7043.3.77.712
8343.3.77.72/3043.3.77.73 to 43.3.77.7443.3.77.752
8443.3.77.76/3043.3.77.77 to 43.3.77.7843.3.77.792
8543.3.77.80/3043.3.77.81 to 43.3.77.8243.3.77.832
8643.3.77.84/3043.3.77.85 to 43.3.77.8643.3.77.872
8743.3.77.88/3043.3.77.89 to 43.3.77.9043.3.77.912
8843.3.77.92/3043.3.77.93 to 43.3.77.9443.3.77.952
8943.3.77.96/3043.3.77.97 to 43.3.77.9843.3.77.992
9043.3.77.100/3043.3.77.101 to 43.3.77.10243.3.77.1032
9143.3.77.104/3043.3.77.105 to 43.3.77.10643.3.77.1072
9243.3.77.108/3043.3.77.109 to 43.3.77.11043.3.77.1112
9343.3.77.112/3043.3.77.113 to 43.3.77.11443.3.77.1152
9443.3.77.116/3043.3.77.117 to 43.3.77.11843.3.77.1192
9543.3.77.120/3043.3.77.121 to 43.3.77.12243.3.77.1232
9643.3.77.124/3043.3.77.125 to 43.3.77.12643.3.77.1272
9743.3.77.128/3043.3.77.129 to 43.3.77.13043.3.77.1312
9843.3.77.132/3043.3.77.133 to 43.3.77.13443.3.77.1352
9943.3.77.136/3043.3.77.137 to 43.3.77.13843.3.77.1392
10043.3.77.140/3043.3.77.141 to 43.3.77.14243.3.77.1432
10143.3.77.144/3043.3.77.145 to 43.3.77.14643.3.77.1472
10243.3.77.148/3043.3.77.149 to 43.3.77.15043.3.77.1512
10343.3.77.152/3043.3.77.153 to 43.3.77.15443.3.77.1552
10443.3.77.156/3043.3.77.157 to 43.3.77.15843.3.77.1592
10543.3.77.160/3043.3.77.161 to 43.3.77.16243.3.77.1632
10643.3.77.164/3043.3.77.165 to 43.3.77.16643.3.77.1672
10743.3.77.168/3043.3.77.169 to 43.3.77.17043.3.77.1712
10843.3.77.172/3043.3.77.173 to 43.3.77.17443.3.77.1752
10943.3.77.176/3043.3.77.177 to 43.3.77.17843.3.77.1792
11043.3.77.180/3043.3.77.181 to 43.3.77.18243.3.77.1832
11143.3.77.184/3043.3.77.185 to 43.3.77.18643.3.77.1872
11243.3.77.188/3043.3.77.189 to 43.3.77.19043.3.77.1912
11343.3.77.192/3043.3.77.193 to 43.3.77.19443.3.77.1952
11443.3.77.196/3043.3.77.197 to 43.3.77.19843.3.77.1992
11543.3.77.200/3043.3.77.201 to 43.3.77.20243.3.77.2032
11643.3.77.204/3043.3.77.205 to 43.3.77.20643.3.77.2072
11743.3.77.208/3043.3.77.209 to 43.3.77.21043.3.77.2112
11843.3.77.212/3043.3.77.213 to 43.3.77.21443.3.77.2152
11943.3.77.216/3043.3.77.217 to 43.3.77.21843.3.77.2192
12043.3.77.220/3043.3.77.221 to 43.3.77.22243.3.77.2232
12143.3.77.224/3043.3.77.225 to 43.3.77.22643.3.77.2272
12243.3.77.228/3043.3.77.229 to 43.3.77.23043.3.77.2312
12343.3.77.232/3043.3.77.233 to 43.3.77.23443.3.77.2352
12443.3.77.236/3043.3.77.237 to 43.3.77.23843.3.77.2392
12543.3.77.240/3043.3.77.241 to 43.3.77.24243.3.77.2432
12643.3.77.244/3043.3.77.245 to 43.3.77.24643.3.77.2472
12743.3.77.248/3043.3.77.249 to 43.3.77.25043.3.77.2512
12843.3.77.252/3043.3.77.253 to 43.3.77.25443.3.77.2552
12943.3.78.0/3043.3.78.1 to 43.3.78.243.3.78.32
13043.3.78.4/3043.3.78.5 to 43.3.78.643.3.78.72
13143.3.78.8/3043.3.78.9 to 43.3.78.1043.3.78.112
13243.3.78.12/3043.3.78.13 to 43.3.78.1443.3.78.152
13343.3.78.16/3043.3.78.17 to 43.3.78.1843.3.78.192
13443.3.78.20/3043.3.78.21 to 43.3.78.2243.3.78.232
13543.3.78.24/3043.3.78.25 to 43.3.78.2643.3.78.272
13643.3.78.28/3043.3.78.29 to 43.3.78.3043.3.78.312
13743.3.78.32/3043.3.78.33 to 43.3.78.3443.3.78.352
13843.3.78.36/3043.3.78.37 to 43.3.78.3843.3.78.392
13943.3.78.40/3043.3.78.41 to 43.3.78.4243.3.78.432
14043.3.78.44/3043.3.78.45 to 43.3.78.4643.3.78.472
14143.3.78.48/3043.3.78.49 to 43.3.78.5043.3.78.512
14243.3.78.52/3043.3.78.53 to 43.3.78.5443.3.78.552
14343.3.78.56/3043.3.78.57 to 43.3.78.5843.3.78.592
14443.3.78.60/3043.3.78.61 to 43.3.78.6243.3.78.632
14543.3.78.64/3043.3.78.65 to 43.3.78.6643.3.78.672
14643.3.78.68/3043.3.78.69 to 43.3.78.7043.3.78.712
14743.3.78.72/3043.3.78.73 to 43.3.78.7443.3.78.752
14843.3.78.76/3043.3.78.77 to 43.3.78.7843.3.78.792
14943.3.78.80/3043.3.78.81 to 43.3.78.8243.3.78.832
15043.3.78.84/3043.3.78.85 to 43.3.78.8643.3.78.872
15143.3.78.88/3043.3.78.89 to 43.3.78.9043.3.78.912
15243.3.78.92/3043.3.78.93 to 43.3.78.9443.3.78.952
15343.3.78.96/3043.3.78.97 to 43.3.78.9843.3.78.992
15443.3.78.100/3043.3.78.101 to 43.3.78.10243.3.78.1032
15543.3.78.104/3043.3.78.105 to 43.3.78.10643.3.78.1072
15643.3.78.108/3043.3.78.109 to 43.3.78.11043.3.78.1112
15743.3.78.112/3043.3.78.113 to 43.3.78.11443.3.78.1152
15843.3.78.116/3043.3.78.117 to 43.3.78.11843.3.78.1192
15943.3.78.120/3043.3.78.121 to 43.3.78.12243.3.78.1232
16043.3.78.124/3043.3.78.125 to 43.3.78.12643.3.78.1272
16143.3.78.128/3043.3.78.129 to 43.3.78.13043.3.78.1312
16243.3.78.132/3043.3.78.133 to 43.3.78.13443.3.78.1352
16343.3.78.136/3043.3.78.137 to 43.3.78.13843.3.78.1392
16443.3.78.140/3043.3.78.141 to 43.3.78.14243.3.78.1432
16543.3.78.144/3043.3.78.145 to 43.3.78.14643.3.78.1472
16643.3.78.148/3043.3.78.149 to 43.3.78.15043.3.78.1512
16743.3.78.152/3043.3.78.153 to 43.3.78.15443.3.78.1552
16843.3.78.156/3043.3.78.157 to 43.3.78.15843.3.78.1592
16943.3.78.160/3043.3.78.161 to 43.3.78.16243.3.78.1632
17043.3.78.164/3043.3.78.165 to 43.3.78.16643.3.78.1672
17143.3.78.168/3043.3.78.169 to 43.3.78.17043.3.78.1712
17243.3.78.172/3043.3.78.173 to 43.3.78.17443.3.78.1752
17343.3.78.176/3043.3.78.177 to 43.3.78.17843.3.78.1792
17443.3.78.180/3043.3.78.181 to 43.3.78.18243.3.78.1832
17543.3.78.184/3043.3.78.185 to 43.3.78.18643.3.78.1872
17643.3.78.188/3043.3.78.189 to 43.3.78.19043.3.78.1912
17743.3.78.192/3043.3.78.193 to 43.3.78.19443.3.78.1952
17843.3.78.196/3043.3.78.197 to 43.3.78.19843.3.78.1992
17943.3.78.200/3043.3.78.201 to 43.3.78.20243.3.78.2032
18043.3.78.204/3043.3.78.205 to 43.3.78.20643.3.78.2072
18143.3.78.208/3043.3.78.209 to 43.3.78.21043.3.78.2112
18243.3.78.212/3043.3.78.213 to 43.3.78.21443.3.78.2152
18343.3.78.216/3043.3.78.217 to 43.3.78.21843.3.78.2192
18443.3.78.220/3043.3.78.221 to 43.3.78.22243.3.78.2232
18543.3.78.224/3043.3.78.225 to 43.3.78.22643.3.78.2272
18643.3.78.228/3043.3.78.229 to 43.3.78.23043.3.78.2312
18743.3.78.232/3043.3.78.233 to 43.3.78.23443.3.78.2352
18843.3.78.236/3043.3.78.237 to 43.3.78.23843.3.78.2392
18943.3.78.240/3043.3.78.241 to 43.3.78.24243.3.78.2432
19043.3.78.244/3043.3.78.245 to 43.3.78.24643.3.78.2472
19143.3.78.248/3043.3.78.249 to 43.3.78.25043.3.78.2512
19243.3.78.252/3043.3.78.253 to 43.3.78.25443.3.78.2552
19343.3.79.0/3043.3.79.1 to 43.3.79.243.3.79.32
19443.3.79.4/3043.3.79.5 to 43.3.79.643.3.79.72
19543.3.79.8/3043.3.79.9 to 43.3.79.1043.3.79.112
19643.3.79.12/3043.3.79.13 to 43.3.79.1443.3.79.152
19743.3.79.16/3043.3.79.17 to 43.3.79.1843.3.79.192
19843.3.79.20/3043.3.79.21 to 43.3.79.2243.3.79.232
19943.3.79.24/3043.3.79.25 to 43.3.79.2643.3.79.272
20043.3.79.28/3043.3.79.29 to 43.3.79.3043.3.79.312
20143.3.79.32/3043.3.79.33 to 43.3.79.3443.3.79.352
20243.3.79.36/3043.3.79.37 to 43.3.79.3843.3.79.392
20343.3.79.40/3043.3.79.41 to 43.3.79.4243.3.79.432
20443.3.79.44/3043.3.79.45 to 43.3.79.4643.3.79.472
20543.3.79.48/3043.3.79.49 to 43.3.79.5043.3.79.512
20643.3.79.52/3043.3.79.53 to 43.3.79.5443.3.79.552
20743.3.79.56/3043.3.79.57 to 43.3.79.5843.3.79.592
20843.3.79.60/3043.3.79.61 to 43.3.79.6243.3.79.632
20943.3.79.64/3043.3.79.65 to 43.3.79.6643.3.79.672
21043.3.79.68/3043.3.79.69 to 43.3.79.7043.3.79.712
21143.3.79.72/3043.3.79.73 to 43.3.79.7443.3.79.752
21243.3.79.76/3043.3.79.77 to 43.3.79.7843.3.79.792
21343.3.79.80/3043.3.79.81 to 43.3.79.8243.3.79.832
21443.3.79.84/3043.3.79.85 to 43.3.79.8643.3.79.872
21543.3.79.88/3043.3.79.89 to 43.3.79.9043.3.79.912
21643.3.79.92/3043.3.79.93 to 43.3.79.9443.3.79.952
21743.3.79.96/3043.3.79.97 to 43.3.79.9843.3.79.992
21843.3.79.100/3043.3.79.101 to 43.3.79.10243.3.79.1032
21943.3.79.104/3043.3.79.105 to 43.3.79.10643.3.79.1072
22043.3.79.108/3043.3.79.109 to 43.3.79.11043.3.79.1112
22143.3.79.112/3043.3.79.113 to 43.3.79.11443.3.79.1152
22243.3.79.116/3043.3.79.117 to 43.3.79.11843.3.79.1192
22343.3.79.120/3043.3.79.121 to 43.3.79.12243.3.79.1232
22443.3.79.124/3043.3.79.125 to 43.3.79.12643.3.79.1272
22543.3.79.128/3043.3.79.129 to 43.3.79.13043.3.79.1312
22643.3.79.132/3043.3.79.133 to 43.3.79.13443.3.79.1352
22743.3.79.136/3043.3.79.137 to 43.3.79.13843.3.79.1392
22843.3.79.140/3043.3.79.141 to 43.3.79.14243.3.79.1432
22943.3.79.144/3043.3.79.145 to 43.3.79.14643.3.79.1472
23043.3.79.148/3043.3.79.149 to 43.3.79.15043.3.79.1512
23143.3.79.152/3043.3.79.153 to 43.3.79.15443.3.79.1552
23243.3.79.156/3043.3.79.157 to 43.3.79.15843.3.79.1592
23343.3.79.160/3043.3.79.161 to 43.3.79.16243.3.79.1632
23443.3.79.164/3043.3.79.165 to 43.3.79.16643.3.79.1672
23543.3.79.168/3043.3.79.169 to 43.3.79.17043.3.79.1712
23643.3.79.172/3043.3.79.173 to 43.3.79.17443.3.79.1752
23743.3.79.176/3043.3.79.177 to 43.3.79.17843.3.79.1792
23843.3.79.180/3043.3.79.181 to 43.3.79.18243.3.79.1832
23943.3.79.184/3043.3.79.185 to 43.3.79.18643.3.79.1872
24043.3.79.188/3043.3.79.189 to 43.3.79.19043.3.79.1912
24143.3.79.192/3043.3.79.193 to 43.3.79.19443.3.79.1952
24243.3.79.196/3043.3.79.197 to 43.3.79.19843.3.79.1992
24343.3.79.200/3043.3.79.201 to 43.3.79.20243.3.79.2032
24443.3.79.204/3043.3.79.205 to 43.3.79.20643.3.79.2072
24543.3.79.208/3043.3.79.209 to 43.3.79.21043.3.79.2112
24643.3.79.212/3043.3.79.213 to 43.3.79.21443.3.79.2152
24743.3.79.216/3043.3.79.217 to 43.3.79.21843.3.79.2192
24843.3.79.220/3043.3.79.221 to 43.3.79.22243.3.79.2232
24943.3.79.224/3043.3.79.225 to 43.3.79.22643.3.79.2272
25043.3.79.228/3043.3.79.229 to 43.3.79.23043.3.79.2312
25143.3.79.232/3043.3.79.233 to 43.3.79.23443.3.79.2352
25243.3.79.236/3043.3.79.237 to 43.3.79.23843.3.79.2392
25343.3.79.240/3043.3.79.241 to 43.3.79.24243.3.79.2432
25443.3.79.244/3043.3.79.245 to 43.3.79.24643.3.79.2472
25543.3.79.248/3043.3.79.249 to 43.3.79.25043.3.79.2512
25643.3.79.252/3043.3.79.253 to 43.3.79.25443.3.79.2552

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