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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.

Network75.167.12.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
75.167.12.0
Broadcast address
75.167.15.255
First usable
75.167.12.1
Last usable
75.167.15.254
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 4BA70C00 · Integer 1269238784 to 1269239807
Reverse DNS zones
12.167.75.in-addr.arpa
13.167.75.in-addr.arpa
14.167.75.in-addr.arpa
15.167.75.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
Address01001011.10100111.00001100.0000000075.167.12.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network01001011.10100111.00001100.0000000075.167.12.0
Broadcast01001011.10100111.00001111.1111111175.167.15.255
Split into smaller subnets/30
/23 (2)/24 (4)/25 (8)/26 (16)/27 (32)/28 (64)/29 (128)/30 (256)/31 (512)/32 (1,024)

75.167.12.0/22 makes 256 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
175.167.12.0/3075.167.12.1 to 75.167.12.275.167.12.32
275.167.12.4/3075.167.12.5 to 75.167.12.675.167.12.72
375.167.12.8/3075.167.12.9 to 75.167.12.1075.167.12.112
475.167.12.12/3075.167.12.13 to 75.167.12.1475.167.12.152
575.167.12.16/3075.167.12.17 to 75.167.12.1875.167.12.192
675.167.12.20/3075.167.12.21 to 75.167.12.2275.167.12.232
775.167.12.24/3075.167.12.25 to 75.167.12.2675.167.12.272
875.167.12.28/3075.167.12.29 to 75.167.12.3075.167.12.312
975.167.12.32/3075.167.12.33 to 75.167.12.3475.167.12.352
1075.167.12.36/3075.167.12.37 to 75.167.12.3875.167.12.392
1175.167.12.40/3075.167.12.41 to 75.167.12.4275.167.12.432
1275.167.12.44/3075.167.12.45 to 75.167.12.4675.167.12.472
1375.167.12.48/3075.167.12.49 to 75.167.12.5075.167.12.512
1475.167.12.52/3075.167.12.53 to 75.167.12.5475.167.12.552
1575.167.12.56/3075.167.12.57 to 75.167.12.5875.167.12.592
1675.167.12.60/3075.167.12.61 to 75.167.12.6275.167.12.632
1775.167.12.64/3075.167.12.65 to 75.167.12.6675.167.12.672
1875.167.12.68/3075.167.12.69 to 75.167.12.7075.167.12.712
1975.167.12.72/3075.167.12.73 to 75.167.12.7475.167.12.752
2075.167.12.76/3075.167.12.77 to 75.167.12.7875.167.12.792
2175.167.12.80/3075.167.12.81 to 75.167.12.8275.167.12.832
2275.167.12.84/3075.167.12.85 to 75.167.12.8675.167.12.872
2375.167.12.88/3075.167.12.89 to 75.167.12.9075.167.12.912
2475.167.12.92/3075.167.12.93 to 75.167.12.9475.167.12.952
2575.167.12.96/3075.167.12.97 to 75.167.12.9875.167.12.992
2675.167.12.100/3075.167.12.101 to 75.167.12.10275.167.12.1032
2775.167.12.104/3075.167.12.105 to 75.167.12.10675.167.12.1072
2875.167.12.108/3075.167.12.109 to 75.167.12.11075.167.12.1112
2975.167.12.112/3075.167.12.113 to 75.167.12.11475.167.12.1152
3075.167.12.116/3075.167.12.117 to 75.167.12.11875.167.12.1192
3175.167.12.120/3075.167.12.121 to 75.167.12.12275.167.12.1232
3275.167.12.124/3075.167.12.125 to 75.167.12.12675.167.12.1272
3375.167.12.128/3075.167.12.129 to 75.167.12.13075.167.12.1312
3475.167.12.132/3075.167.12.133 to 75.167.12.13475.167.12.1352
3575.167.12.136/3075.167.12.137 to 75.167.12.13875.167.12.1392
3675.167.12.140/3075.167.12.141 to 75.167.12.14275.167.12.1432
3775.167.12.144/3075.167.12.145 to 75.167.12.14675.167.12.1472
3875.167.12.148/3075.167.12.149 to 75.167.12.15075.167.12.1512
3975.167.12.152/3075.167.12.153 to 75.167.12.15475.167.12.1552
4075.167.12.156/3075.167.12.157 to 75.167.12.15875.167.12.1592
4175.167.12.160/3075.167.12.161 to 75.167.12.16275.167.12.1632
4275.167.12.164/3075.167.12.165 to 75.167.12.16675.167.12.1672
4375.167.12.168/3075.167.12.169 to 75.167.12.17075.167.12.1712
4475.167.12.172/3075.167.12.173 to 75.167.12.17475.167.12.1752
4575.167.12.176/3075.167.12.177 to 75.167.12.17875.167.12.1792
4675.167.12.180/3075.167.12.181 to 75.167.12.18275.167.12.1832
4775.167.12.184/3075.167.12.185 to 75.167.12.18675.167.12.1872
4875.167.12.188/3075.167.12.189 to 75.167.12.19075.167.12.1912
4975.167.12.192/3075.167.12.193 to 75.167.12.19475.167.12.1952
5075.167.12.196/3075.167.12.197 to 75.167.12.19875.167.12.1992
5175.167.12.200/3075.167.12.201 to 75.167.12.20275.167.12.2032
5275.167.12.204/3075.167.12.205 to 75.167.12.20675.167.12.2072
5375.167.12.208/3075.167.12.209 to 75.167.12.21075.167.12.2112
5475.167.12.212/3075.167.12.213 to 75.167.12.21475.167.12.2152
5575.167.12.216/3075.167.12.217 to 75.167.12.21875.167.12.2192
5675.167.12.220/3075.167.12.221 to 75.167.12.22275.167.12.2232
5775.167.12.224/3075.167.12.225 to 75.167.12.22675.167.12.2272
5875.167.12.228/3075.167.12.229 to 75.167.12.23075.167.12.2312
5975.167.12.232/3075.167.12.233 to 75.167.12.23475.167.12.2352
6075.167.12.236/3075.167.12.237 to 75.167.12.23875.167.12.2392
6175.167.12.240/3075.167.12.241 to 75.167.12.24275.167.12.2432
6275.167.12.244/3075.167.12.245 to 75.167.12.24675.167.12.2472
6375.167.12.248/3075.167.12.249 to 75.167.12.25075.167.12.2512
6475.167.12.252/3075.167.12.253 to 75.167.12.25475.167.12.2552
6575.167.13.0/3075.167.13.1 to 75.167.13.275.167.13.32
6675.167.13.4/3075.167.13.5 to 75.167.13.675.167.13.72
6775.167.13.8/3075.167.13.9 to 75.167.13.1075.167.13.112
6875.167.13.12/3075.167.13.13 to 75.167.13.1475.167.13.152
6975.167.13.16/3075.167.13.17 to 75.167.13.1875.167.13.192
7075.167.13.20/3075.167.13.21 to 75.167.13.2275.167.13.232
7175.167.13.24/3075.167.13.25 to 75.167.13.2675.167.13.272
7275.167.13.28/3075.167.13.29 to 75.167.13.3075.167.13.312
7375.167.13.32/3075.167.13.33 to 75.167.13.3475.167.13.352
7475.167.13.36/3075.167.13.37 to 75.167.13.3875.167.13.392
7575.167.13.40/3075.167.13.41 to 75.167.13.4275.167.13.432
7675.167.13.44/3075.167.13.45 to 75.167.13.4675.167.13.472
7775.167.13.48/3075.167.13.49 to 75.167.13.5075.167.13.512
7875.167.13.52/3075.167.13.53 to 75.167.13.5475.167.13.552
7975.167.13.56/3075.167.13.57 to 75.167.13.5875.167.13.592
8075.167.13.60/3075.167.13.61 to 75.167.13.6275.167.13.632
8175.167.13.64/3075.167.13.65 to 75.167.13.6675.167.13.672
8275.167.13.68/3075.167.13.69 to 75.167.13.7075.167.13.712
8375.167.13.72/3075.167.13.73 to 75.167.13.7475.167.13.752
8475.167.13.76/3075.167.13.77 to 75.167.13.7875.167.13.792
8575.167.13.80/3075.167.13.81 to 75.167.13.8275.167.13.832
8675.167.13.84/3075.167.13.85 to 75.167.13.8675.167.13.872
8775.167.13.88/3075.167.13.89 to 75.167.13.9075.167.13.912
8875.167.13.92/3075.167.13.93 to 75.167.13.9475.167.13.952
8975.167.13.96/3075.167.13.97 to 75.167.13.9875.167.13.992
9075.167.13.100/3075.167.13.101 to 75.167.13.10275.167.13.1032
9175.167.13.104/3075.167.13.105 to 75.167.13.10675.167.13.1072
9275.167.13.108/3075.167.13.109 to 75.167.13.11075.167.13.1112
9375.167.13.112/3075.167.13.113 to 75.167.13.11475.167.13.1152
9475.167.13.116/3075.167.13.117 to 75.167.13.11875.167.13.1192
9575.167.13.120/3075.167.13.121 to 75.167.13.12275.167.13.1232
9675.167.13.124/3075.167.13.125 to 75.167.13.12675.167.13.1272
9775.167.13.128/3075.167.13.129 to 75.167.13.13075.167.13.1312
9875.167.13.132/3075.167.13.133 to 75.167.13.13475.167.13.1352
9975.167.13.136/3075.167.13.137 to 75.167.13.13875.167.13.1392
10075.167.13.140/3075.167.13.141 to 75.167.13.14275.167.13.1432
10175.167.13.144/3075.167.13.145 to 75.167.13.14675.167.13.1472
10275.167.13.148/3075.167.13.149 to 75.167.13.15075.167.13.1512
10375.167.13.152/3075.167.13.153 to 75.167.13.15475.167.13.1552
10475.167.13.156/3075.167.13.157 to 75.167.13.15875.167.13.1592
10575.167.13.160/3075.167.13.161 to 75.167.13.16275.167.13.1632
10675.167.13.164/3075.167.13.165 to 75.167.13.16675.167.13.1672
10775.167.13.168/3075.167.13.169 to 75.167.13.17075.167.13.1712
10875.167.13.172/3075.167.13.173 to 75.167.13.17475.167.13.1752
10975.167.13.176/3075.167.13.177 to 75.167.13.17875.167.13.1792
11075.167.13.180/3075.167.13.181 to 75.167.13.18275.167.13.1832
11175.167.13.184/3075.167.13.185 to 75.167.13.18675.167.13.1872
11275.167.13.188/3075.167.13.189 to 75.167.13.19075.167.13.1912
11375.167.13.192/3075.167.13.193 to 75.167.13.19475.167.13.1952
11475.167.13.196/3075.167.13.197 to 75.167.13.19875.167.13.1992
11575.167.13.200/3075.167.13.201 to 75.167.13.20275.167.13.2032
11675.167.13.204/3075.167.13.205 to 75.167.13.20675.167.13.2072
11775.167.13.208/3075.167.13.209 to 75.167.13.21075.167.13.2112
11875.167.13.212/3075.167.13.213 to 75.167.13.21475.167.13.2152
11975.167.13.216/3075.167.13.217 to 75.167.13.21875.167.13.2192
12075.167.13.220/3075.167.13.221 to 75.167.13.22275.167.13.2232
12175.167.13.224/3075.167.13.225 to 75.167.13.22675.167.13.2272
12275.167.13.228/3075.167.13.229 to 75.167.13.23075.167.13.2312
12375.167.13.232/3075.167.13.233 to 75.167.13.23475.167.13.2352
12475.167.13.236/3075.167.13.237 to 75.167.13.23875.167.13.2392
12575.167.13.240/3075.167.13.241 to 75.167.13.24275.167.13.2432
12675.167.13.244/3075.167.13.245 to 75.167.13.24675.167.13.2472
12775.167.13.248/3075.167.13.249 to 75.167.13.25075.167.13.2512
12875.167.13.252/3075.167.13.253 to 75.167.13.25475.167.13.2552
12975.167.14.0/3075.167.14.1 to 75.167.14.275.167.14.32
13075.167.14.4/3075.167.14.5 to 75.167.14.675.167.14.72
13175.167.14.8/3075.167.14.9 to 75.167.14.1075.167.14.112
13275.167.14.12/3075.167.14.13 to 75.167.14.1475.167.14.152
13375.167.14.16/3075.167.14.17 to 75.167.14.1875.167.14.192
13475.167.14.20/3075.167.14.21 to 75.167.14.2275.167.14.232
13575.167.14.24/3075.167.14.25 to 75.167.14.2675.167.14.272
13675.167.14.28/3075.167.14.29 to 75.167.14.3075.167.14.312
13775.167.14.32/3075.167.14.33 to 75.167.14.3475.167.14.352
13875.167.14.36/3075.167.14.37 to 75.167.14.3875.167.14.392
13975.167.14.40/3075.167.14.41 to 75.167.14.4275.167.14.432
14075.167.14.44/3075.167.14.45 to 75.167.14.4675.167.14.472
14175.167.14.48/3075.167.14.49 to 75.167.14.5075.167.14.512
14275.167.14.52/3075.167.14.53 to 75.167.14.5475.167.14.552
14375.167.14.56/3075.167.14.57 to 75.167.14.5875.167.14.592
14475.167.14.60/3075.167.14.61 to 75.167.14.6275.167.14.632
14575.167.14.64/3075.167.14.65 to 75.167.14.6675.167.14.672
14675.167.14.68/3075.167.14.69 to 75.167.14.7075.167.14.712
14775.167.14.72/3075.167.14.73 to 75.167.14.7475.167.14.752
14875.167.14.76/3075.167.14.77 to 75.167.14.7875.167.14.792
14975.167.14.80/3075.167.14.81 to 75.167.14.8275.167.14.832
15075.167.14.84/3075.167.14.85 to 75.167.14.8675.167.14.872
15175.167.14.88/3075.167.14.89 to 75.167.14.9075.167.14.912
15275.167.14.92/3075.167.14.93 to 75.167.14.9475.167.14.952
15375.167.14.96/3075.167.14.97 to 75.167.14.9875.167.14.992
15475.167.14.100/3075.167.14.101 to 75.167.14.10275.167.14.1032
15575.167.14.104/3075.167.14.105 to 75.167.14.10675.167.14.1072
15675.167.14.108/3075.167.14.109 to 75.167.14.11075.167.14.1112
15775.167.14.112/3075.167.14.113 to 75.167.14.11475.167.14.1152
15875.167.14.116/3075.167.14.117 to 75.167.14.11875.167.14.1192
15975.167.14.120/3075.167.14.121 to 75.167.14.12275.167.14.1232
16075.167.14.124/3075.167.14.125 to 75.167.14.12675.167.14.1272
16175.167.14.128/3075.167.14.129 to 75.167.14.13075.167.14.1312
16275.167.14.132/3075.167.14.133 to 75.167.14.13475.167.14.1352
16375.167.14.136/3075.167.14.137 to 75.167.14.13875.167.14.1392
16475.167.14.140/3075.167.14.141 to 75.167.14.14275.167.14.1432
16575.167.14.144/3075.167.14.145 to 75.167.14.14675.167.14.1472
16675.167.14.148/3075.167.14.149 to 75.167.14.15075.167.14.1512
16775.167.14.152/3075.167.14.153 to 75.167.14.15475.167.14.1552
16875.167.14.156/3075.167.14.157 to 75.167.14.15875.167.14.1592
16975.167.14.160/3075.167.14.161 to 75.167.14.16275.167.14.1632
17075.167.14.164/3075.167.14.165 to 75.167.14.16675.167.14.1672
17175.167.14.168/3075.167.14.169 to 75.167.14.17075.167.14.1712
17275.167.14.172/3075.167.14.173 to 75.167.14.17475.167.14.1752
17375.167.14.176/3075.167.14.177 to 75.167.14.17875.167.14.1792
17475.167.14.180/3075.167.14.181 to 75.167.14.18275.167.14.1832
17575.167.14.184/3075.167.14.185 to 75.167.14.18675.167.14.1872
17675.167.14.188/3075.167.14.189 to 75.167.14.19075.167.14.1912
17775.167.14.192/3075.167.14.193 to 75.167.14.19475.167.14.1952
17875.167.14.196/3075.167.14.197 to 75.167.14.19875.167.14.1992
17975.167.14.200/3075.167.14.201 to 75.167.14.20275.167.14.2032
18075.167.14.204/3075.167.14.205 to 75.167.14.20675.167.14.2072
18175.167.14.208/3075.167.14.209 to 75.167.14.21075.167.14.2112
18275.167.14.212/3075.167.14.213 to 75.167.14.21475.167.14.2152
18375.167.14.216/3075.167.14.217 to 75.167.14.21875.167.14.2192
18475.167.14.220/3075.167.14.221 to 75.167.14.22275.167.14.2232
18575.167.14.224/3075.167.14.225 to 75.167.14.22675.167.14.2272
18675.167.14.228/3075.167.14.229 to 75.167.14.23075.167.14.2312
18775.167.14.232/3075.167.14.233 to 75.167.14.23475.167.14.2352
18875.167.14.236/3075.167.14.237 to 75.167.14.23875.167.14.2392
18975.167.14.240/3075.167.14.241 to 75.167.14.24275.167.14.2432
19075.167.14.244/3075.167.14.245 to 75.167.14.24675.167.14.2472
19175.167.14.248/3075.167.14.249 to 75.167.14.25075.167.14.2512
19275.167.14.252/3075.167.14.253 to 75.167.14.25475.167.14.2552
19375.167.15.0/3075.167.15.1 to 75.167.15.275.167.15.32
19475.167.15.4/3075.167.15.5 to 75.167.15.675.167.15.72
19575.167.15.8/3075.167.15.9 to 75.167.15.1075.167.15.112
19675.167.15.12/3075.167.15.13 to 75.167.15.1475.167.15.152
19775.167.15.16/3075.167.15.17 to 75.167.15.1875.167.15.192
19875.167.15.20/3075.167.15.21 to 75.167.15.2275.167.15.232
19975.167.15.24/3075.167.15.25 to 75.167.15.2675.167.15.272
20075.167.15.28/3075.167.15.29 to 75.167.15.3075.167.15.312
20175.167.15.32/3075.167.15.33 to 75.167.15.3475.167.15.352
20275.167.15.36/3075.167.15.37 to 75.167.15.3875.167.15.392
20375.167.15.40/3075.167.15.41 to 75.167.15.4275.167.15.432
20475.167.15.44/3075.167.15.45 to 75.167.15.4675.167.15.472
20575.167.15.48/3075.167.15.49 to 75.167.15.5075.167.15.512
20675.167.15.52/3075.167.15.53 to 75.167.15.5475.167.15.552
20775.167.15.56/3075.167.15.57 to 75.167.15.5875.167.15.592
20875.167.15.60/3075.167.15.61 to 75.167.15.6275.167.15.632
20975.167.15.64/3075.167.15.65 to 75.167.15.6675.167.15.672
21075.167.15.68/3075.167.15.69 to 75.167.15.7075.167.15.712
21175.167.15.72/3075.167.15.73 to 75.167.15.7475.167.15.752
21275.167.15.76/3075.167.15.77 to 75.167.15.7875.167.15.792
21375.167.15.80/3075.167.15.81 to 75.167.15.8275.167.15.832
21475.167.15.84/3075.167.15.85 to 75.167.15.8675.167.15.872
21575.167.15.88/3075.167.15.89 to 75.167.15.9075.167.15.912
21675.167.15.92/3075.167.15.93 to 75.167.15.9475.167.15.952
21775.167.15.96/3075.167.15.97 to 75.167.15.9875.167.15.992
21875.167.15.100/3075.167.15.101 to 75.167.15.10275.167.15.1032
21975.167.15.104/3075.167.15.105 to 75.167.15.10675.167.15.1072
22075.167.15.108/3075.167.15.109 to 75.167.15.11075.167.15.1112
22175.167.15.112/3075.167.15.113 to 75.167.15.11475.167.15.1152
22275.167.15.116/3075.167.15.117 to 75.167.15.11875.167.15.1192
22375.167.15.120/3075.167.15.121 to 75.167.15.12275.167.15.1232
22475.167.15.124/3075.167.15.125 to 75.167.15.12675.167.15.1272
22575.167.15.128/3075.167.15.129 to 75.167.15.13075.167.15.1312
22675.167.15.132/3075.167.15.133 to 75.167.15.13475.167.15.1352
22775.167.15.136/3075.167.15.137 to 75.167.15.13875.167.15.1392
22875.167.15.140/3075.167.15.141 to 75.167.15.14275.167.15.1432
22975.167.15.144/3075.167.15.145 to 75.167.15.14675.167.15.1472
23075.167.15.148/3075.167.15.149 to 75.167.15.15075.167.15.1512
23175.167.15.152/3075.167.15.153 to 75.167.15.15475.167.15.1552
23275.167.15.156/3075.167.15.157 to 75.167.15.15875.167.15.1592
23375.167.15.160/3075.167.15.161 to 75.167.15.16275.167.15.1632
23475.167.15.164/3075.167.15.165 to 75.167.15.16675.167.15.1672
23575.167.15.168/3075.167.15.169 to 75.167.15.17075.167.15.1712
23675.167.15.172/3075.167.15.173 to 75.167.15.17475.167.15.1752
23775.167.15.176/3075.167.15.177 to 75.167.15.17875.167.15.1792
23875.167.15.180/3075.167.15.181 to 75.167.15.18275.167.15.1832
23975.167.15.184/3075.167.15.185 to 75.167.15.18675.167.15.1872
24075.167.15.188/3075.167.15.189 to 75.167.15.19075.167.15.1912
24175.167.15.192/3075.167.15.193 to 75.167.15.19475.167.15.1952
24275.167.15.196/3075.167.15.197 to 75.167.15.19875.167.15.1992
24375.167.15.200/3075.167.15.201 to 75.167.15.20275.167.15.2032
24475.167.15.204/3075.167.15.205 to 75.167.15.20675.167.15.2072
24575.167.15.208/3075.167.15.209 to 75.167.15.21075.167.15.2112
24675.167.15.212/3075.167.15.213 to 75.167.15.21475.167.15.2152
24775.167.15.216/3075.167.15.217 to 75.167.15.21875.167.15.2192
24875.167.15.220/3075.167.15.221 to 75.167.15.22275.167.15.2232
24975.167.15.224/3075.167.15.225 to 75.167.15.22675.167.15.2272
25075.167.15.228/3075.167.15.229 to 75.167.15.23075.167.15.2312
25175.167.15.232/3075.167.15.233 to 75.167.15.23475.167.15.2352
25275.167.15.236/3075.167.15.237 to 75.167.15.23875.167.15.2392
25375.167.15.240/3075.167.15.241 to 75.167.15.24275.167.15.2432
25475.167.15.244/3075.167.15.245 to 75.167.15.24675.167.15.2472
25575.167.15.248/3075.167.15.249 to 75.167.15.25075.167.15.2512
25675.167.15.252/3075.167.15.253 to 75.167.15.25475.167.15.2552

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.