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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.

Network58.0.84.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
58.0.84.0
Broadcast address
58.0.87.255
First usable
58.0.84.1
Last usable
58.0.87.254
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 3A005400 · Integer 973100032 to 973101055
Reverse DNS zones
84.0.58.in-addr.arpa
85.0.58.in-addr.arpa
86.0.58.in-addr.arpa
87.0.58.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
Address00111010.00000000.01010100.0000000058.0.84.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network00111010.00000000.01010100.0000000058.0.84.0
Broadcast00111010.00000000.01010111.1111111158.0.87.255
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)

58.0.84.0/22 makes 256 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
158.0.84.0/3058.0.84.1 to 58.0.84.258.0.84.32
258.0.84.4/3058.0.84.5 to 58.0.84.658.0.84.72
358.0.84.8/3058.0.84.9 to 58.0.84.1058.0.84.112
458.0.84.12/3058.0.84.13 to 58.0.84.1458.0.84.152
558.0.84.16/3058.0.84.17 to 58.0.84.1858.0.84.192
658.0.84.20/3058.0.84.21 to 58.0.84.2258.0.84.232
758.0.84.24/3058.0.84.25 to 58.0.84.2658.0.84.272
858.0.84.28/3058.0.84.29 to 58.0.84.3058.0.84.312
958.0.84.32/3058.0.84.33 to 58.0.84.3458.0.84.352
1058.0.84.36/3058.0.84.37 to 58.0.84.3858.0.84.392
1158.0.84.40/3058.0.84.41 to 58.0.84.4258.0.84.432
1258.0.84.44/3058.0.84.45 to 58.0.84.4658.0.84.472
1358.0.84.48/3058.0.84.49 to 58.0.84.5058.0.84.512
1458.0.84.52/3058.0.84.53 to 58.0.84.5458.0.84.552
1558.0.84.56/3058.0.84.57 to 58.0.84.5858.0.84.592
1658.0.84.60/3058.0.84.61 to 58.0.84.6258.0.84.632
1758.0.84.64/3058.0.84.65 to 58.0.84.6658.0.84.672
1858.0.84.68/3058.0.84.69 to 58.0.84.7058.0.84.712
1958.0.84.72/3058.0.84.73 to 58.0.84.7458.0.84.752
2058.0.84.76/3058.0.84.77 to 58.0.84.7858.0.84.792
2158.0.84.80/3058.0.84.81 to 58.0.84.8258.0.84.832
2258.0.84.84/3058.0.84.85 to 58.0.84.8658.0.84.872
2358.0.84.88/3058.0.84.89 to 58.0.84.9058.0.84.912
2458.0.84.92/3058.0.84.93 to 58.0.84.9458.0.84.952
2558.0.84.96/3058.0.84.97 to 58.0.84.9858.0.84.992
2658.0.84.100/3058.0.84.101 to 58.0.84.10258.0.84.1032
2758.0.84.104/3058.0.84.105 to 58.0.84.10658.0.84.1072
2858.0.84.108/3058.0.84.109 to 58.0.84.11058.0.84.1112
2958.0.84.112/3058.0.84.113 to 58.0.84.11458.0.84.1152
3058.0.84.116/3058.0.84.117 to 58.0.84.11858.0.84.1192
3158.0.84.120/3058.0.84.121 to 58.0.84.12258.0.84.1232
3258.0.84.124/3058.0.84.125 to 58.0.84.12658.0.84.1272
3358.0.84.128/3058.0.84.129 to 58.0.84.13058.0.84.1312
3458.0.84.132/3058.0.84.133 to 58.0.84.13458.0.84.1352
3558.0.84.136/3058.0.84.137 to 58.0.84.13858.0.84.1392
3658.0.84.140/3058.0.84.141 to 58.0.84.14258.0.84.1432
3758.0.84.144/3058.0.84.145 to 58.0.84.14658.0.84.1472
3858.0.84.148/3058.0.84.149 to 58.0.84.15058.0.84.1512
3958.0.84.152/3058.0.84.153 to 58.0.84.15458.0.84.1552
4058.0.84.156/3058.0.84.157 to 58.0.84.15858.0.84.1592
4158.0.84.160/3058.0.84.161 to 58.0.84.16258.0.84.1632
4258.0.84.164/3058.0.84.165 to 58.0.84.16658.0.84.1672
4358.0.84.168/3058.0.84.169 to 58.0.84.17058.0.84.1712
4458.0.84.172/3058.0.84.173 to 58.0.84.17458.0.84.1752
4558.0.84.176/3058.0.84.177 to 58.0.84.17858.0.84.1792
4658.0.84.180/3058.0.84.181 to 58.0.84.18258.0.84.1832
4758.0.84.184/3058.0.84.185 to 58.0.84.18658.0.84.1872
4858.0.84.188/3058.0.84.189 to 58.0.84.19058.0.84.1912
4958.0.84.192/3058.0.84.193 to 58.0.84.19458.0.84.1952
5058.0.84.196/3058.0.84.197 to 58.0.84.19858.0.84.1992
5158.0.84.200/3058.0.84.201 to 58.0.84.20258.0.84.2032
5258.0.84.204/3058.0.84.205 to 58.0.84.20658.0.84.2072
5358.0.84.208/3058.0.84.209 to 58.0.84.21058.0.84.2112
5458.0.84.212/3058.0.84.213 to 58.0.84.21458.0.84.2152
5558.0.84.216/3058.0.84.217 to 58.0.84.21858.0.84.2192
5658.0.84.220/3058.0.84.221 to 58.0.84.22258.0.84.2232
5758.0.84.224/3058.0.84.225 to 58.0.84.22658.0.84.2272
5858.0.84.228/3058.0.84.229 to 58.0.84.23058.0.84.2312
5958.0.84.232/3058.0.84.233 to 58.0.84.23458.0.84.2352
6058.0.84.236/3058.0.84.237 to 58.0.84.23858.0.84.2392
6158.0.84.240/3058.0.84.241 to 58.0.84.24258.0.84.2432
6258.0.84.244/3058.0.84.245 to 58.0.84.24658.0.84.2472
6358.0.84.248/3058.0.84.249 to 58.0.84.25058.0.84.2512
6458.0.84.252/3058.0.84.253 to 58.0.84.25458.0.84.2552
6558.0.85.0/3058.0.85.1 to 58.0.85.258.0.85.32
6658.0.85.4/3058.0.85.5 to 58.0.85.658.0.85.72
6758.0.85.8/3058.0.85.9 to 58.0.85.1058.0.85.112
6858.0.85.12/3058.0.85.13 to 58.0.85.1458.0.85.152
6958.0.85.16/3058.0.85.17 to 58.0.85.1858.0.85.192
7058.0.85.20/3058.0.85.21 to 58.0.85.2258.0.85.232
7158.0.85.24/3058.0.85.25 to 58.0.85.2658.0.85.272
7258.0.85.28/3058.0.85.29 to 58.0.85.3058.0.85.312
7358.0.85.32/3058.0.85.33 to 58.0.85.3458.0.85.352
7458.0.85.36/3058.0.85.37 to 58.0.85.3858.0.85.392
7558.0.85.40/3058.0.85.41 to 58.0.85.4258.0.85.432
7658.0.85.44/3058.0.85.45 to 58.0.85.4658.0.85.472
7758.0.85.48/3058.0.85.49 to 58.0.85.5058.0.85.512
7858.0.85.52/3058.0.85.53 to 58.0.85.5458.0.85.552
7958.0.85.56/3058.0.85.57 to 58.0.85.5858.0.85.592
8058.0.85.60/3058.0.85.61 to 58.0.85.6258.0.85.632
8158.0.85.64/3058.0.85.65 to 58.0.85.6658.0.85.672
8258.0.85.68/3058.0.85.69 to 58.0.85.7058.0.85.712
8358.0.85.72/3058.0.85.73 to 58.0.85.7458.0.85.752
8458.0.85.76/3058.0.85.77 to 58.0.85.7858.0.85.792
8558.0.85.80/3058.0.85.81 to 58.0.85.8258.0.85.832
8658.0.85.84/3058.0.85.85 to 58.0.85.8658.0.85.872
8758.0.85.88/3058.0.85.89 to 58.0.85.9058.0.85.912
8858.0.85.92/3058.0.85.93 to 58.0.85.9458.0.85.952
8958.0.85.96/3058.0.85.97 to 58.0.85.9858.0.85.992
9058.0.85.100/3058.0.85.101 to 58.0.85.10258.0.85.1032
9158.0.85.104/3058.0.85.105 to 58.0.85.10658.0.85.1072
9258.0.85.108/3058.0.85.109 to 58.0.85.11058.0.85.1112
9358.0.85.112/3058.0.85.113 to 58.0.85.11458.0.85.1152
9458.0.85.116/3058.0.85.117 to 58.0.85.11858.0.85.1192
9558.0.85.120/3058.0.85.121 to 58.0.85.12258.0.85.1232
9658.0.85.124/3058.0.85.125 to 58.0.85.12658.0.85.1272
9758.0.85.128/3058.0.85.129 to 58.0.85.13058.0.85.1312
9858.0.85.132/3058.0.85.133 to 58.0.85.13458.0.85.1352
9958.0.85.136/3058.0.85.137 to 58.0.85.13858.0.85.1392
10058.0.85.140/3058.0.85.141 to 58.0.85.14258.0.85.1432
10158.0.85.144/3058.0.85.145 to 58.0.85.14658.0.85.1472
10258.0.85.148/3058.0.85.149 to 58.0.85.15058.0.85.1512
10358.0.85.152/3058.0.85.153 to 58.0.85.15458.0.85.1552
10458.0.85.156/3058.0.85.157 to 58.0.85.15858.0.85.1592
10558.0.85.160/3058.0.85.161 to 58.0.85.16258.0.85.1632
10658.0.85.164/3058.0.85.165 to 58.0.85.16658.0.85.1672
10758.0.85.168/3058.0.85.169 to 58.0.85.17058.0.85.1712
10858.0.85.172/3058.0.85.173 to 58.0.85.17458.0.85.1752
10958.0.85.176/3058.0.85.177 to 58.0.85.17858.0.85.1792
11058.0.85.180/3058.0.85.181 to 58.0.85.18258.0.85.1832
11158.0.85.184/3058.0.85.185 to 58.0.85.18658.0.85.1872
11258.0.85.188/3058.0.85.189 to 58.0.85.19058.0.85.1912
11358.0.85.192/3058.0.85.193 to 58.0.85.19458.0.85.1952
11458.0.85.196/3058.0.85.197 to 58.0.85.19858.0.85.1992
11558.0.85.200/3058.0.85.201 to 58.0.85.20258.0.85.2032
11658.0.85.204/3058.0.85.205 to 58.0.85.20658.0.85.2072
11758.0.85.208/3058.0.85.209 to 58.0.85.21058.0.85.2112
11858.0.85.212/3058.0.85.213 to 58.0.85.21458.0.85.2152
11958.0.85.216/3058.0.85.217 to 58.0.85.21858.0.85.2192
12058.0.85.220/3058.0.85.221 to 58.0.85.22258.0.85.2232
12158.0.85.224/3058.0.85.225 to 58.0.85.22658.0.85.2272
12258.0.85.228/3058.0.85.229 to 58.0.85.23058.0.85.2312
12358.0.85.232/3058.0.85.233 to 58.0.85.23458.0.85.2352
12458.0.85.236/3058.0.85.237 to 58.0.85.23858.0.85.2392
12558.0.85.240/3058.0.85.241 to 58.0.85.24258.0.85.2432
12658.0.85.244/3058.0.85.245 to 58.0.85.24658.0.85.2472
12758.0.85.248/3058.0.85.249 to 58.0.85.25058.0.85.2512
12858.0.85.252/3058.0.85.253 to 58.0.85.25458.0.85.2552
12958.0.86.0/3058.0.86.1 to 58.0.86.258.0.86.32
13058.0.86.4/3058.0.86.5 to 58.0.86.658.0.86.72
13158.0.86.8/3058.0.86.9 to 58.0.86.1058.0.86.112
13258.0.86.12/3058.0.86.13 to 58.0.86.1458.0.86.152
13358.0.86.16/3058.0.86.17 to 58.0.86.1858.0.86.192
13458.0.86.20/3058.0.86.21 to 58.0.86.2258.0.86.232
13558.0.86.24/3058.0.86.25 to 58.0.86.2658.0.86.272
13658.0.86.28/3058.0.86.29 to 58.0.86.3058.0.86.312
13758.0.86.32/3058.0.86.33 to 58.0.86.3458.0.86.352
13858.0.86.36/3058.0.86.37 to 58.0.86.3858.0.86.392
13958.0.86.40/3058.0.86.41 to 58.0.86.4258.0.86.432
14058.0.86.44/3058.0.86.45 to 58.0.86.4658.0.86.472
14158.0.86.48/3058.0.86.49 to 58.0.86.5058.0.86.512
14258.0.86.52/3058.0.86.53 to 58.0.86.5458.0.86.552
14358.0.86.56/3058.0.86.57 to 58.0.86.5858.0.86.592
14458.0.86.60/3058.0.86.61 to 58.0.86.6258.0.86.632
14558.0.86.64/3058.0.86.65 to 58.0.86.6658.0.86.672
14658.0.86.68/3058.0.86.69 to 58.0.86.7058.0.86.712
14758.0.86.72/3058.0.86.73 to 58.0.86.7458.0.86.752
14858.0.86.76/3058.0.86.77 to 58.0.86.7858.0.86.792
14958.0.86.80/3058.0.86.81 to 58.0.86.8258.0.86.832
15058.0.86.84/3058.0.86.85 to 58.0.86.8658.0.86.872
15158.0.86.88/3058.0.86.89 to 58.0.86.9058.0.86.912
15258.0.86.92/3058.0.86.93 to 58.0.86.9458.0.86.952
15358.0.86.96/3058.0.86.97 to 58.0.86.9858.0.86.992
15458.0.86.100/3058.0.86.101 to 58.0.86.10258.0.86.1032
15558.0.86.104/3058.0.86.105 to 58.0.86.10658.0.86.1072
15658.0.86.108/3058.0.86.109 to 58.0.86.11058.0.86.1112
15758.0.86.112/3058.0.86.113 to 58.0.86.11458.0.86.1152
15858.0.86.116/3058.0.86.117 to 58.0.86.11858.0.86.1192
15958.0.86.120/3058.0.86.121 to 58.0.86.12258.0.86.1232
16058.0.86.124/3058.0.86.125 to 58.0.86.12658.0.86.1272
16158.0.86.128/3058.0.86.129 to 58.0.86.13058.0.86.1312
16258.0.86.132/3058.0.86.133 to 58.0.86.13458.0.86.1352
16358.0.86.136/3058.0.86.137 to 58.0.86.13858.0.86.1392
16458.0.86.140/3058.0.86.141 to 58.0.86.14258.0.86.1432
16558.0.86.144/3058.0.86.145 to 58.0.86.14658.0.86.1472
16658.0.86.148/3058.0.86.149 to 58.0.86.15058.0.86.1512
16758.0.86.152/3058.0.86.153 to 58.0.86.15458.0.86.1552
16858.0.86.156/3058.0.86.157 to 58.0.86.15858.0.86.1592
16958.0.86.160/3058.0.86.161 to 58.0.86.16258.0.86.1632
17058.0.86.164/3058.0.86.165 to 58.0.86.16658.0.86.1672
17158.0.86.168/3058.0.86.169 to 58.0.86.17058.0.86.1712
17258.0.86.172/3058.0.86.173 to 58.0.86.17458.0.86.1752
17358.0.86.176/3058.0.86.177 to 58.0.86.17858.0.86.1792
17458.0.86.180/3058.0.86.181 to 58.0.86.18258.0.86.1832
17558.0.86.184/3058.0.86.185 to 58.0.86.18658.0.86.1872
17658.0.86.188/3058.0.86.189 to 58.0.86.19058.0.86.1912
17758.0.86.192/3058.0.86.193 to 58.0.86.19458.0.86.1952
17858.0.86.196/3058.0.86.197 to 58.0.86.19858.0.86.1992
17958.0.86.200/3058.0.86.201 to 58.0.86.20258.0.86.2032
18058.0.86.204/3058.0.86.205 to 58.0.86.20658.0.86.2072
18158.0.86.208/3058.0.86.209 to 58.0.86.21058.0.86.2112
18258.0.86.212/3058.0.86.213 to 58.0.86.21458.0.86.2152
18358.0.86.216/3058.0.86.217 to 58.0.86.21858.0.86.2192
18458.0.86.220/3058.0.86.221 to 58.0.86.22258.0.86.2232
18558.0.86.224/3058.0.86.225 to 58.0.86.22658.0.86.2272
18658.0.86.228/3058.0.86.229 to 58.0.86.23058.0.86.2312
18758.0.86.232/3058.0.86.233 to 58.0.86.23458.0.86.2352
18858.0.86.236/3058.0.86.237 to 58.0.86.23858.0.86.2392
18958.0.86.240/3058.0.86.241 to 58.0.86.24258.0.86.2432
19058.0.86.244/3058.0.86.245 to 58.0.86.24658.0.86.2472
19158.0.86.248/3058.0.86.249 to 58.0.86.25058.0.86.2512
19258.0.86.252/3058.0.86.253 to 58.0.86.25458.0.86.2552
19358.0.87.0/3058.0.87.1 to 58.0.87.258.0.87.32
19458.0.87.4/3058.0.87.5 to 58.0.87.658.0.87.72
19558.0.87.8/3058.0.87.9 to 58.0.87.1058.0.87.112
19658.0.87.12/3058.0.87.13 to 58.0.87.1458.0.87.152
19758.0.87.16/3058.0.87.17 to 58.0.87.1858.0.87.192
19858.0.87.20/3058.0.87.21 to 58.0.87.2258.0.87.232
19958.0.87.24/3058.0.87.25 to 58.0.87.2658.0.87.272
20058.0.87.28/3058.0.87.29 to 58.0.87.3058.0.87.312
20158.0.87.32/3058.0.87.33 to 58.0.87.3458.0.87.352
20258.0.87.36/3058.0.87.37 to 58.0.87.3858.0.87.392
20358.0.87.40/3058.0.87.41 to 58.0.87.4258.0.87.432
20458.0.87.44/3058.0.87.45 to 58.0.87.4658.0.87.472
20558.0.87.48/3058.0.87.49 to 58.0.87.5058.0.87.512
20658.0.87.52/3058.0.87.53 to 58.0.87.5458.0.87.552
20758.0.87.56/3058.0.87.57 to 58.0.87.5858.0.87.592
20858.0.87.60/3058.0.87.61 to 58.0.87.6258.0.87.632
20958.0.87.64/3058.0.87.65 to 58.0.87.6658.0.87.672
21058.0.87.68/3058.0.87.69 to 58.0.87.7058.0.87.712
21158.0.87.72/3058.0.87.73 to 58.0.87.7458.0.87.752
21258.0.87.76/3058.0.87.77 to 58.0.87.7858.0.87.792
21358.0.87.80/3058.0.87.81 to 58.0.87.8258.0.87.832
21458.0.87.84/3058.0.87.85 to 58.0.87.8658.0.87.872
21558.0.87.88/3058.0.87.89 to 58.0.87.9058.0.87.912
21658.0.87.92/3058.0.87.93 to 58.0.87.9458.0.87.952
21758.0.87.96/3058.0.87.97 to 58.0.87.9858.0.87.992
21858.0.87.100/3058.0.87.101 to 58.0.87.10258.0.87.1032
21958.0.87.104/3058.0.87.105 to 58.0.87.10658.0.87.1072
22058.0.87.108/3058.0.87.109 to 58.0.87.11058.0.87.1112
22158.0.87.112/3058.0.87.113 to 58.0.87.11458.0.87.1152
22258.0.87.116/3058.0.87.117 to 58.0.87.11858.0.87.1192
22358.0.87.120/3058.0.87.121 to 58.0.87.12258.0.87.1232
22458.0.87.124/3058.0.87.125 to 58.0.87.12658.0.87.1272
22558.0.87.128/3058.0.87.129 to 58.0.87.13058.0.87.1312
22658.0.87.132/3058.0.87.133 to 58.0.87.13458.0.87.1352
22758.0.87.136/3058.0.87.137 to 58.0.87.13858.0.87.1392
22858.0.87.140/3058.0.87.141 to 58.0.87.14258.0.87.1432
22958.0.87.144/3058.0.87.145 to 58.0.87.14658.0.87.1472
23058.0.87.148/3058.0.87.149 to 58.0.87.15058.0.87.1512
23158.0.87.152/3058.0.87.153 to 58.0.87.15458.0.87.1552
23258.0.87.156/3058.0.87.157 to 58.0.87.15858.0.87.1592
23358.0.87.160/3058.0.87.161 to 58.0.87.16258.0.87.1632
23458.0.87.164/3058.0.87.165 to 58.0.87.16658.0.87.1672
23558.0.87.168/3058.0.87.169 to 58.0.87.17058.0.87.1712
23658.0.87.172/3058.0.87.173 to 58.0.87.17458.0.87.1752
23758.0.87.176/3058.0.87.177 to 58.0.87.17858.0.87.1792
23858.0.87.180/3058.0.87.181 to 58.0.87.18258.0.87.1832
23958.0.87.184/3058.0.87.185 to 58.0.87.18658.0.87.1872
24058.0.87.188/3058.0.87.189 to 58.0.87.19058.0.87.1912
24158.0.87.192/3058.0.87.193 to 58.0.87.19458.0.87.1952
24258.0.87.196/3058.0.87.197 to 58.0.87.19858.0.87.1992
24358.0.87.200/3058.0.87.201 to 58.0.87.20258.0.87.2032
24458.0.87.204/3058.0.87.205 to 58.0.87.20658.0.87.2072
24558.0.87.208/3058.0.87.209 to 58.0.87.21058.0.87.2112
24658.0.87.212/3058.0.87.213 to 58.0.87.21458.0.87.2152
24758.0.87.216/3058.0.87.217 to 58.0.87.21858.0.87.2192
24858.0.87.220/3058.0.87.221 to 58.0.87.22258.0.87.2232
24958.0.87.224/3058.0.87.225 to 58.0.87.22658.0.87.2272
25058.0.87.228/3058.0.87.229 to 58.0.87.23058.0.87.2312
25158.0.87.232/3058.0.87.233 to 58.0.87.23458.0.87.2352
25258.0.87.236/3058.0.87.237 to 58.0.87.23858.0.87.2392
25358.0.87.240/3058.0.87.241 to 58.0.87.24258.0.87.2432
25458.0.87.244/3058.0.87.245 to 58.0.87.24658.0.87.2472
25558.0.87.248/3058.0.87.249 to 58.0.87.25058.0.87.2512
25658.0.87.252/3058.0.87.253 to 58.0.87.25458.0.87.2552

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.