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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.

Network96.16.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
96.16.0.0
Broadcast address
96.16.255.255
First usable
96.16.0.1
Last usable
96.16.255.254
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 60100000 · Integer 1611661312 to 1611726847
Reverse DNS zone
16.96.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01100000.00010000..00000000.0000000096.16.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01100000.00010000..00000000.0000000096.16.0.0
Broadcast01100000.00010000..11111111.1111111196.16.255.255
Split into smaller subnets/27
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

96.16.0.0/16 makes 2,048 subnets of /27; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
196.16.0.0/2796.16.0.1 to 96.16.0.3096.16.0.3130
296.16.0.32/2796.16.0.33 to 96.16.0.6296.16.0.6330
396.16.0.64/2796.16.0.65 to 96.16.0.9496.16.0.9530
496.16.0.96/2796.16.0.97 to 96.16.0.12696.16.0.12730
596.16.0.128/2796.16.0.129 to 96.16.0.15896.16.0.15930
696.16.0.160/2796.16.0.161 to 96.16.0.19096.16.0.19130
796.16.0.192/2796.16.0.193 to 96.16.0.22296.16.0.22330
896.16.0.224/2796.16.0.225 to 96.16.0.25496.16.0.25530
996.16.1.0/2796.16.1.1 to 96.16.1.3096.16.1.3130
1096.16.1.32/2796.16.1.33 to 96.16.1.6296.16.1.6330
1196.16.1.64/2796.16.1.65 to 96.16.1.9496.16.1.9530
1296.16.1.96/2796.16.1.97 to 96.16.1.12696.16.1.12730
1396.16.1.128/2796.16.1.129 to 96.16.1.15896.16.1.15930
1496.16.1.160/2796.16.1.161 to 96.16.1.19096.16.1.19130
1596.16.1.192/2796.16.1.193 to 96.16.1.22296.16.1.22330
1696.16.1.224/2796.16.1.225 to 96.16.1.25496.16.1.25530
1796.16.2.0/2796.16.2.1 to 96.16.2.3096.16.2.3130
1896.16.2.32/2796.16.2.33 to 96.16.2.6296.16.2.6330
1996.16.2.64/2796.16.2.65 to 96.16.2.9496.16.2.9530
2096.16.2.96/2796.16.2.97 to 96.16.2.12696.16.2.12730
2196.16.2.128/2796.16.2.129 to 96.16.2.15896.16.2.15930
2296.16.2.160/2796.16.2.161 to 96.16.2.19096.16.2.19130
2396.16.2.192/2796.16.2.193 to 96.16.2.22296.16.2.22330
2496.16.2.224/2796.16.2.225 to 96.16.2.25496.16.2.25530
2596.16.3.0/2796.16.3.1 to 96.16.3.3096.16.3.3130
2696.16.3.32/2796.16.3.33 to 96.16.3.6296.16.3.6330
2796.16.3.64/2796.16.3.65 to 96.16.3.9496.16.3.9530
2896.16.3.96/2796.16.3.97 to 96.16.3.12696.16.3.12730
2996.16.3.128/2796.16.3.129 to 96.16.3.15896.16.3.15930
3096.16.3.160/2796.16.3.161 to 96.16.3.19096.16.3.19130
3196.16.3.192/2796.16.3.193 to 96.16.3.22296.16.3.22330
3296.16.3.224/2796.16.3.225 to 96.16.3.25496.16.3.25530
3396.16.4.0/2796.16.4.1 to 96.16.4.3096.16.4.3130
3496.16.4.32/2796.16.4.33 to 96.16.4.6296.16.4.6330
3596.16.4.64/2796.16.4.65 to 96.16.4.9496.16.4.9530
3696.16.4.96/2796.16.4.97 to 96.16.4.12696.16.4.12730
3796.16.4.128/2796.16.4.129 to 96.16.4.15896.16.4.15930
3896.16.4.160/2796.16.4.161 to 96.16.4.19096.16.4.19130
3996.16.4.192/2796.16.4.193 to 96.16.4.22296.16.4.22330
4096.16.4.224/2796.16.4.225 to 96.16.4.25496.16.4.25530
4196.16.5.0/2796.16.5.1 to 96.16.5.3096.16.5.3130
4296.16.5.32/2796.16.5.33 to 96.16.5.6296.16.5.6330
4396.16.5.64/2796.16.5.65 to 96.16.5.9496.16.5.9530
4496.16.5.96/2796.16.5.97 to 96.16.5.12696.16.5.12730
4596.16.5.128/2796.16.5.129 to 96.16.5.15896.16.5.15930
4696.16.5.160/2796.16.5.161 to 96.16.5.19096.16.5.19130
4796.16.5.192/2796.16.5.193 to 96.16.5.22296.16.5.22330
4896.16.5.224/2796.16.5.225 to 96.16.5.25496.16.5.25530
4996.16.6.0/2796.16.6.1 to 96.16.6.3096.16.6.3130
5096.16.6.32/2796.16.6.33 to 96.16.6.6296.16.6.6330
5196.16.6.64/2796.16.6.65 to 96.16.6.9496.16.6.9530
5296.16.6.96/2796.16.6.97 to 96.16.6.12696.16.6.12730
5396.16.6.128/2796.16.6.129 to 96.16.6.15896.16.6.15930
5496.16.6.160/2796.16.6.161 to 96.16.6.19096.16.6.19130
5596.16.6.192/2796.16.6.193 to 96.16.6.22296.16.6.22330
5696.16.6.224/2796.16.6.225 to 96.16.6.25496.16.6.25530
5796.16.7.0/2796.16.7.1 to 96.16.7.3096.16.7.3130
5896.16.7.32/2796.16.7.33 to 96.16.7.6296.16.7.6330
5996.16.7.64/2796.16.7.65 to 96.16.7.9496.16.7.9530
6096.16.7.96/2796.16.7.97 to 96.16.7.12696.16.7.12730
6196.16.7.128/2796.16.7.129 to 96.16.7.15896.16.7.15930
6296.16.7.160/2796.16.7.161 to 96.16.7.19096.16.7.19130
6396.16.7.192/2796.16.7.193 to 96.16.7.22296.16.7.22330
6496.16.7.224/2796.16.7.225 to 96.16.7.25496.16.7.25530
6596.16.8.0/2796.16.8.1 to 96.16.8.3096.16.8.3130
6696.16.8.32/2796.16.8.33 to 96.16.8.6296.16.8.6330
6796.16.8.64/2796.16.8.65 to 96.16.8.9496.16.8.9530
6896.16.8.96/2796.16.8.97 to 96.16.8.12696.16.8.12730
6996.16.8.128/2796.16.8.129 to 96.16.8.15896.16.8.15930
7096.16.8.160/2796.16.8.161 to 96.16.8.19096.16.8.19130
7196.16.8.192/2796.16.8.193 to 96.16.8.22296.16.8.22330
7296.16.8.224/2796.16.8.225 to 96.16.8.25496.16.8.25530
7396.16.9.0/2796.16.9.1 to 96.16.9.3096.16.9.3130
7496.16.9.32/2796.16.9.33 to 96.16.9.6296.16.9.6330
7596.16.9.64/2796.16.9.65 to 96.16.9.9496.16.9.9530
7696.16.9.96/2796.16.9.97 to 96.16.9.12696.16.9.12730
7796.16.9.128/2796.16.9.129 to 96.16.9.15896.16.9.15930
7896.16.9.160/2796.16.9.161 to 96.16.9.19096.16.9.19130
7996.16.9.192/2796.16.9.193 to 96.16.9.22296.16.9.22330
8096.16.9.224/2796.16.9.225 to 96.16.9.25496.16.9.25530
8196.16.10.0/2796.16.10.1 to 96.16.10.3096.16.10.3130
8296.16.10.32/2796.16.10.33 to 96.16.10.6296.16.10.6330
8396.16.10.64/2796.16.10.65 to 96.16.10.9496.16.10.9530
8496.16.10.96/2796.16.10.97 to 96.16.10.12696.16.10.12730
8596.16.10.128/2796.16.10.129 to 96.16.10.15896.16.10.15930
8696.16.10.160/2796.16.10.161 to 96.16.10.19096.16.10.19130
8796.16.10.192/2796.16.10.193 to 96.16.10.22296.16.10.22330
8896.16.10.224/2796.16.10.225 to 96.16.10.25496.16.10.25530
8996.16.11.0/2796.16.11.1 to 96.16.11.3096.16.11.3130
9096.16.11.32/2796.16.11.33 to 96.16.11.6296.16.11.6330
9196.16.11.64/2796.16.11.65 to 96.16.11.9496.16.11.9530
9296.16.11.96/2796.16.11.97 to 96.16.11.12696.16.11.12730
9396.16.11.128/2796.16.11.129 to 96.16.11.15896.16.11.15930
9496.16.11.160/2796.16.11.161 to 96.16.11.19096.16.11.19130
9596.16.11.192/2796.16.11.193 to 96.16.11.22296.16.11.22330
9696.16.11.224/2796.16.11.225 to 96.16.11.25496.16.11.25530
9796.16.12.0/2796.16.12.1 to 96.16.12.3096.16.12.3130
9896.16.12.32/2796.16.12.33 to 96.16.12.6296.16.12.6330
9996.16.12.64/2796.16.12.65 to 96.16.12.9496.16.12.9530
10096.16.12.96/2796.16.12.97 to 96.16.12.12696.16.12.12730
10196.16.12.128/2796.16.12.129 to 96.16.12.15896.16.12.15930
10296.16.12.160/2796.16.12.161 to 96.16.12.19096.16.12.19130
10396.16.12.192/2796.16.12.193 to 96.16.12.22296.16.12.22330
10496.16.12.224/2796.16.12.225 to 96.16.12.25496.16.12.25530
10596.16.13.0/2796.16.13.1 to 96.16.13.3096.16.13.3130
10696.16.13.32/2796.16.13.33 to 96.16.13.6296.16.13.6330
10796.16.13.64/2796.16.13.65 to 96.16.13.9496.16.13.9530
10896.16.13.96/2796.16.13.97 to 96.16.13.12696.16.13.12730
10996.16.13.128/2796.16.13.129 to 96.16.13.15896.16.13.15930
11096.16.13.160/2796.16.13.161 to 96.16.13.19096.16.13.19130
11196.16.13.192/2796.16.13.193 to 96.16.13.22296.16.13.22330
11296.16.13.224/2796.16.13.225 to 96.16.13.25496.16.13.25530
11396.16.14.0/2796.16.14.1 to 96.16.14.3096.16.14.3130
11496.16.14.32/2796.16.14.33 to 96.16.14.6296.16.14.6330
11596.16.14.64/2796.16.14.65 to 96.16.14.9496.16.14.9530
11696.16.14.96/2796.16.14.97 to 96.16.14.12696.16.14.12730
11796.16.14.128/2796.16.14.129 to 96.16.14.15896.16.14.15930
11896.16.14.160/2796.16.14.161 to 96.16.14.19096.16.14.19130
11996.16.14.192/2796.16.14.193 to 96.16.14.22296.16.14.22330
12096.16.14.224/2796.16.14.225 to 96.16.14.25496.16.14.25530
12196.16.15.0/2796.16.15.1 to 96.16.15.3096.16.15.3130
12296.16.15.32/2796.16.15.33 to 96.16.15.6296.16.15.6330
12396.16.15.64/2796.16.15.65 to 96.16.15.9496.16.15.9530
12496.16.15.96/2796.16.15.97 to 96.16.15.12696.16.15.12730
12596.16.15.128/2796.16.15.129 to 96.16.15.15896.16.15.15930
12696.16.15.160/2796.16.15.161 to 96.16.15.19096.16.15.19130
12796.16.15.192/2796.16.15.193 to 96.16.15.22296.16.15.22330
12896.16.15.224/2796.16.15.225 to 96.16.15.25496.16.15.25530
12996.16.16.0/2796.16.16.1 to 96.16.16.3096.16.16.3130
13096.16.16.32/2796.16.16.33 to 96.16.16.6296.16.16.6330
13196.16.16.64/2796.16.16.65 to 96.16.16.9496.16.16.9530
13296.16.16.96/2796.16.16.97 to 96.16.16.12696.16.16.12730
13396.16.16.128/2796.16.16.129 to 96.16.16.15896.16.16.15930
13496.16.16.160/2796.16.16.161 to 96.16.16.19096.16.16.19130
13596.16.16.192/2796.16.16.193 to 96.16.16.22296.16.16.22330
13696.16.16.224/2796.16.16.225 to 96.16.16.25496.16.16.25530
13796.16.17.0/2796.16.17.1 to 96.16.17.3096.16.17.3130
13896.16.17.32/2796.16.17.33 to 96.16.17.6296.16.17.6330
13996.16.17.64/2796.16.17.65 to 96.16.17.9496.16.17.9530
14096.16.17.96/2796.16.17.97 to 96.16.17.12696.16.17.12730
14196.16.17.128/2796.16.17.129 to 96.16.17.15896.16.17.15930
14296.16.17.160/2796.16.17.161 to 96.16.17.19096.16.17.19130
14396.16.17.192/2796.16.17.193 to 96.16.17.22296.16.17.22330
14496.16.17.224/2796.16.17.225 to 96.16.17.25496.16.17.25530
14596.16.18.0/2796.16.18.1 to 96.16.18.3096.16.18.3130
14696.16.18.32/2796.16.18.33 to 96.16.18.6296.16.18.6330
14796.16.18.64/2796.16.18.65 to 96.16.18.9496.16.18.9530
14896.16.18.96/2796.16.18.97 to 96.16.18.12696.16.18.12730
14996.16.18.128/2796.16.18.129 to 96.16.18.15896.16.18.15930
15096.16.18.160/2796.16.18.161 to 96.16.18.19096.16.18.19130
15196.16.18.192/2796.16.18.193 to 96.16.18.22296.16.18.22330
15296.16.18.224/2796.16.18.225 to 96.16.18.25496.16.18.25530
15396.16.19.0/2796.16.19.1 to 96.16.19.3096.16.19.3130
15496.16.19.32/2796.16.19.33 to 96.16.19.6296.16.19.6330
15596.16.19.64/2796.16.19.65 to 96.16.19.9496.16.19.9530
15696.16.19.96/2796.16.19.97 to 96.16.19.12696.16.19.12730
15796.16.19.128/2796.16.19.129 to 96.16.19.15896.16.19.15930
15896.16.19.160/2796.16.19.161 to 96.16.19.19096.16.19.19130
15996.16.19.192/2796.16.19.193 to 96.16.19.22296.16.19.22330
16096.16.19.224/2796.16.19.225 to 96.16.19.25496.16.19.25530
16196.16.20.0/2796.16.20.1 to 96.16.20.3096.16.20.3130
16296.16.20.32/2796.16.20.33 to 96.16.20.6296.16.20.6330
16396.16.20.64/2796.16.20.65 to 96.16.20.9496.16.20.9530
16496.16.20.96/2796.16.20.97 to 96.16.20.12696.16.20.12730
16596.16.20.128/2796.16.20.129 to 96.16.20.15896.16.20.15930
16696.16.20.160/2796.16.20.161 to 96.16.20.19096.16.20.19130
16796.16.20.192/2796.16.20.193 to 96.16.20.22296.16.20.22330
16896.16.20.224/2796.16.20.225 to 96.16.20.25496.16.20.25530
16996.16.21.0/2796.16.21.1 to 96.16.21.3096.16.21.3130
17096.16.21.32/2796.16.21.33 to 96.16.21.6296.16.21.6330
17196.16.21.64/2796.16.21.65 to 96.16.21.9496.16.21.9530
17296.16.21.96/2796.16.21.97 to 96.16.21.12696.16.21.12730
17396.16.21.128/2796.16.21.129 to 96.16.21.15896.16.21.15930
17496.16.21.160/2796.16.21.161 to 96.16.21.19096.16.21.19130
17596.16.21.192/2796.16.21.193 to 96.16.21.22296.16.21.22330
17696.16.21.224/2796.16.21.225 to 96.16.21.25496.16.21.25530
17796.16.22.0/2796.16.22.1 to 96.16.22.3096.16.22.3130
17896.16.22.32/2796.16.22.33 to 96.16.22.6296.16.22.6330
17996.16.22.64/2796.16.22.65 to 96.16.22.9496.16.22.9530
18096.16.22.96/2796.16.22.97 to 96.16.22.12696.16.22.12730
18196.16.22.128/2796.16.22.129 to 96.16.22.15896.16.22.15930
18296.16.22.160/2796.16.22.161 to 96.16.22.19096.16.22.19130
18396.16.22.192/2796.16.22.193 to 96.16.22.22296.16.22.22330
18496.16.22.224/2796.16.22.225 to 96.16.22.25496.16.22.25530
18596.16.23.0/2796.16.23.1 to 96.16.23.3096.16.23.3130
18696.16.23.32/2796.16.23.33 to 96.16.23.6296.16.23.6330
18796.16.23.64/2796.16.23.65 to 96.16.23.9496.16.23.9530
18896.16.23.96/2796.16.23.97 to 96.16.23.12696.16.23.12730
18996.16.23.128/2796.16.23.129 to 96.16.23.15896.16.23.15930
19096.16.23.160/2796.16.23.161 to 96.16.23.19096.16.23.19130
19196.16.23.192/2796.16.23.193 to 96.16.23.22296.16.23.22330
19296.16.23.224/2796.16.23.225 to 96.16.23.25496.16.23.25530
19396.16.24.0/2796.16.24.1 to 96.16.24.3096.16.24.3130
19496.16.24.32/2796.16.24.33 to 96.16.24.6296.16.24.6330
19596.16.24.64/2796.16.24.65 to 96.16.24.9496.16.24.9530
19696.16.24.96/2796.16.24.97 to 96.16.24.12696.16.24.12730
19796.16.24.128/2796.16.24.129 to 96.16.24.15896.16.24.15930
19896.16.24.160/2796.16.24.161 to 96.16.24.19096.16.24.19130
19996.16.24.192/2796.16.24.193 to 96.16.24.22296.16.24.22330
20096.16.24.224/2796.16.24.225 to 96.16.24.25496.16.24.25530
20196.16.25.0/2796.16.25.1 to 96.16.25.3096.16.25.3130
20296.16.25.32/2796.16.25.33 to 96.16.25.6296.16.25.6330
20396.16.25.64/2796.16.25.65 to 96.16.25.9496.16.25.9530
20496.16.25.96/2796.16.25.97 to 96.16.25.12696.16.25.12730
20596.16.25.128/2796.16.25.129 to 96.16.25.15896.16.25.15930
20696.16.25.160/2796.16.25.161 to 96.16.25.19096.16.25.19130
20796.16.25.192/2796.16.25.193 to 96.16.25.22296.16.25.22330
20896.16.25.224/2796.16.25.225 to 96.16.25.25496.16.25.25530
20996.16.26.0/2796.16.26.1 to 96.16.26.3096.16.26.3130
21096.16.26.32/2796.16.26.33 to 96.16.26.6296.16.26.6330
21196.16.26.64/2796.16.26.65 to 96.16.26.9496.16.26.9530
21296.16.26.96/2796.16.26.97 to 96.16.26.12696.16.26.12730
21396.16.26.128/2796.16.26.129 to 96.16.26.15896.16.26.15930
21496.16.26.160/2796.16.26.161 to 96.16.26.19096.16.26.19130
21596.16.26.192/2796.16.26.193 to 96.16.26.22296.16.26.22330
21696.16.26.224/2796.16.26.225 to 96.16.26.25496.16.26.25530
21796.16.27.0/2796.16.27.1 to 96.16.27.3096.16.27.3130
21896.16.27.32/2796.16.27.33 to 96.16.27.6296.16.27.6330
21996.16.27.64/2796.16.27.65 to 96.16.27.9496.16.27.9530
22096.16.27.96/2796.16.27.97 to 96.16.27.12696.16.27.12730
22196.16.27.128/2796.16.27.129 to 96.16.27.15896.16.27.15930
22296.16.27.160/2796.16.27.161 to 96.16.27.19096.16.27.19130
22396.16.27.192/2796.16.27.193 to 96.16.27.22296.16.27.22330
22496.16.27.224/2796.16.27.225 to 96.16.27.25496.16.27.25530
22596.16.28.0/2796.16.28.1 to 96.16.28.3096.16.28.3130
22696.16.28.32/2796.16.28.33 to 96.16.28.6296.16.28.6330
22796.16.28.64/2796.16.28.65 to 96.16.28.9496.16.28.9530
22896.16.28.96/2796.16.28.97 to 96.16.28.12696.16.28.12730
22996.16.28.128/2796.16.28.129 to 96.16.28.15896.16.28.15930
23096.16.28.160/2796.16.28.161 to 96.16.28.19096.16.28.19130
23196.16.28.192/2796.16.28.193 to 96.16.28.22296.16.28.22330
23296.16.28.224/2796.16.28.225 to 96.16.28.25496.16.28.25530
23396.16.29.0/2796.16.29.1 to 96.16.29.3096.16.29.3130
23496.16.29.32/2796.16.29.33 to 96.16.29.6296.16.29.6330
23596.16.29.64/2796.16.29.65 to 96.16.29.9496.16.29.9530
23696.16.29.96/2796.16.29.97 to 96.16.29.12696.16.29.12730
23796.16.29.128/2796.16.29.129 to 96.16.29.15896.16.29.15930
23896.16.29.160/2796.16.29.161 to 96.16.29.19096.16.29.19130
23996.16.29.192/2796.16.29.193 to 96.16.29.22296.16.29.22330
24096.16.29.224/2796.16.29.225 to 96.16.29.25496.16.29.25530
24196.16.30.0/2796.16.30.1 to 96.16.30.3096.16.30.3130
24296.16.30.32/2796.16.30.33 to 96.16.30.6296.16.30.6330
24396.16.30.64/2796.16.30.65 to 96.16.30.9496.16.30.9530
24496.16.30.96/2796.16.30.97 to 96.16.30.12696.16.30.12730
24596.16.30.128/2796.16.30.129 to 96.16.30.15896.16.30.15930
24696.16.30.160/2796.16.30.161 to 96.16.30.19096.16.30.19130
24796.16.30.192/2796.16.30.193 to 96.16.30.22296.16.30.22330
24896.16.30.224/2796.16.30.225 to 96.16.30.25496.16.30.25530
24996.16.31.0/2796.16.31.1 to 96.16.31.3096.16.31.3130
25096.16.31.32/2796.16.31.33 to 96.16.31.6296.16.31.6330
25196.16.31.64/2796.16.31.65 to 96.16.31.9496.16.31.9530
25296.16.31.96/2796.16.31.97 to 96.16.31.12696.16.31.12730
25396.16.31.128/2796.16.31.129 to 96.16.31.15896.16.31.15930
25496.16.31.160/2796.16.31.161 to 96.16.31.19096.16.31.19130
25596.16.31.192/2796.16.31.193 to 96.16.31.22296.16.31.22330
25696.16.31.224/2796.16.31.225 to 96.16.31.25496.16.31.25530

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.