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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.

Network93.45.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
93.45.0.0
Broadcast address
93.45.255.255
First usable
93.45.0.1
Last usable
93.45.255.254
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 5D2D0000 · Integer 1563230208 to 1563295743
Reverse DNS zone
45.93.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011101.00101101..00000000.0000000093.45.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01011101.00101101..00000000.0000000093.45.0.0
Broadcast01011101.00101101..11111111.1111111193.45.255.255
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)

93.45.0.0/16 makes 2,048 subnets of /27; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
193.45.0.0/2793.45.0.1 to 93.45.0.3093.45.0.3130
293.45.0.32/2793.45.0.33 to 93.45.0.6293.45.0.6330
393.45.0.64/2793.45.0.65 to 93.45.0.9493.45.0.9530
493.45.0.96/2793.45.0.97 to 93.45.0.12693.45.0.12730
593.45.0.128/2793.45.0.129 to 93.45.0.15893.45.0.15930
693.45.0.160/2793.45.0.161 to 93.45.0.19093.45.0.19130
793.45.0.192/2793.45.0.193 to 93.45.0.22293.45.0.22330
893.45.0.224/2793.45.0.225 to 93.45.0.25493.45.0.25530
993.45.1.0/2793.45.1.1 to 93.45.1.3093.45.1.3130
1093.45.1.32/2793.45.1.33 to 93.45.1.6293.45.1.6330
1193.45.1.64/2793.45.1.65 to 93.45.1.9493.45.1.9530
1293.45.1.96/2793.45.1.97 to 93.45.1.12693.45.1.12730
1393.45.1.128/2793.45.1.129 to 93.45.1.15893.45.1.15930
1493.45.1.160/2793.45.1.161 to 93.45.1.19093.45.1.19130
1593.45.1.192/2793.45.1.193 to 93.45.1.22293.45.1.22330
1693.45.1.224/2793.45.1.225 to 93.45.1.25493.45.1.25530
1793.45.2.0/2793.45.2.1 to 93.45.2.3093.45.2.3130
1893.45.2.32/2793.45.2.33 to 93.45.2.6293.45.2.6330
1993.45.2.64/2793.45.2.65 to 93.45.2.9493.45.2.9530
2093.45.2.96/2793.45.2.97 to 93.45.2.12693.45.2.12730
2193.45.2.128/2793.45.2.129 to 93.45.2.15893.45.2.15930
2293.45.2.160/2793.45.2.161 to 93.45.2.19093.45.2.19130
2393.45.2.192/2793.45.2.193 to 93.45.2.22293.45.2.22330
2493.45.2.224/2793.45.2.225 to 93.45.2.25493.45.2.25530
2593.45.3.0/2793.45.3.1 to 93.45.3.3093.45.3.3130
2693.45.3.32/2793.45.3.33 to 93.45.3.6293.45.3.6330
2793.45.3.64/2793.45.3.65 to 93.45.3.9493.45.3.9530
2893.45.3.96/2793.45.3.97 to 93.45.3.12693.45.3.12730
2993.45.3.128/2793.45.3.129 to 93.45.3.15893.45.3.15930
3093.45.3.160/2793.45.3.161 to 93.45.3.19093.45.3.19130
3193.45.3.192/2793.45.3.193 to 93.45.3.22293.45.3.22330
3293.45.3.224/2793.45.3.225 to 93.45.3.25493.45.3.25530
3393.45.4.0/2793.45.4.1 to 93.45.4.3093.45.4.3130
3493.45.4.32/2793.45.4.33 to 93.45.4.6293.45.4.6330
3593.45.4.64/2793.45.4.65 to 93.45.4.9493.45.4.9530
3693.45.4.96/2793.45.4.97 to 93.45.4.12693.45.4.12730
3793.45.4.128/2793.45.4.129 to 93.45.4.15893.45.4.15930
3893.45.4.160/2793.45.4.161 to 93.45.4.19093.45.4.19130
3993.45.4.192/2793.45.4.193 to 93.45.4.22293.45.4.22330
4093.45.4.224/2793.45.4.225 to 93.45.4.25493.45.4.25530
4193.45.5.0/2793.45.5.1 to 93.45.5.3093.45.5.3130
4293.45.5.32/2793.45.5.33 to 93.45.5.6293.45.5.6330
4393.45.5.64/2793.45.5.65 to 93.45.5.9493.45.5.9530
4493.45.5.96/2793.45.5.97 to 93.45.5.12693.45.5.12730
4593.45.5.128/2793.45.5.129 to 93.45.5.15893.45.5.15930
4693.45.5.160/2793.45.5.161 to 93.45.5.19093.45.5.19130
4793.45.5.192/2793.45.5.193 to 93.45.5.22293.45.5.22330
4893.45.5.224/2793.45.5.225 to 93.45.5.25493.45.5.25530
4993.45.6.0/2793.45.6.1 to 93.45.6.3093.45.6.3130
5093.45.6.32/2793.45.6.33 to 93.45.6.6293.45.6.6330
5193.45.6.64/2793.45.6.65 to 93.45.6.9493.45.6.9530
5293.45.6.96/2793.45.6.97 to 93.45.6.12693.45.6.12730
5393.45.6.128/2793.45.6.129 to 93.45.6.15893.45.6.15930
5493.45.6.160/2793.45.6.161 to 93.45.6.19093.45.6.19130
5593.45.6.192/2793.45.6.193 to 93.45.6.22293.45.6.22330
5693.45.6.224/2793.45.6.225 to 93.45.6.25493.45.6.25530
5793.45.7.0/2793.45.7.1 to 93.45.7.3093.45.7.3130
5893.45.7.32/2793.45.7.33 to 93.45.7.6293.45.7.6330
5993.45.7.64/2793.45.7.65 to 93.45.7.9493.45.7.9530
6093.45.7.96/2793.45.7.97 to 93.45.7.12693.45.7.12730
6193.45.7.128/2793.45.7.129 to 93.45.7.15893.45.7.15930
6293.45.7.160/2793.45.7.161 to 93.45.7.19093.45.7.19130
6393.45.7.192/2793.45.7.193 to 93.45.7.22293.45.7.22330
6493.45.7.224/2793.45.7.225 to 93.45.7.25493.45.7.25530
6593.45.8.0/2793.45.8.1 to 93.45.8.3093.45.8.3130
6693.45.8.32/2793.45.8.33 to 93.45.8.6293.45.8.6330
6793.45.8.64/2793.45.8.65 to 93.45.8.9493.45.8.9530
6893.45.8.96/2793.45.8.97 to 93.45.8.12693.45.8.12730
6993.45.8.128/2793.45.8.129 to 93.45.8.15893.45.8.15930
7093.45.8.160/2793.45.8.161 to 93.45.8.19093.45.8.19130
7193.45.8.192/2793.45.8.193 to 93.45.8.22293.45.8.22330
7293.45.8.224/2793.45.8.225 to 93.45.8.25493.45.8.25530
7393.45.9.0/2793.45.9.1 to 93.45.9.3093.45.9.3130
7493.45.9.32/2793.45.9.33 to 93.45.9.6293.45.9.6330
7593.45.9.64/2793.45.9.65 to 93.45.9.9493.45.9.9530
7693.45.9.96/2793.45.9.97 to 93.45.9.12693.45.9.12730
7793.45.9.128/2793.45.9.129 to 93.45.9.15893.45.9.15930
7893.45.9.160/2793.45.9.161 to 93.45.9.19093.45.9.19130
7993.45.9.192/2793.45.9.193 to 93.45.9.22293.45.9.22330
8093.45.9.224/2793.45.9.225 to 93.45.9.25493.45.9.25530
8193.45.10.0/2793.45.10.1 to 93.45.10.3093.45.10.3130
8293.45.10.32/2793.45.10.33 to 93.45.10.6293.45.10.6330
8393.45.10.64/2793.45.10.65 to 93.45.10.9493.45.10.9530
8493.45.10.96/2793.45.10.97 to 93.45.10.12693.45.10.12730
8593.45.10.128/2793.45.10.129 to 93.45.10.15893.45.10.15930
8693.45.10.160/2793.45.10.161 to 93.45.10.19093.45.10.19130
8793.45.10.192/2793.45.10.193 to 93.45.10.22293.45.10.22330
8893.45.10.224/2793.45.10.225 to 93.45.10.25493.45.10.25530
8993.45.11.0/2793.45.11.1 to 93.45.11.3093.45.11.3130
9093.45.11.32/2793.45.11.33 to 93.45.11.6293.45.11.6330
9193.45.11.64/2793.45.11.65 to 93.45.11.9493.45.11.9530
9293.45.11.96/2793.45.11.97 to 93.45.11.12693.45.11.12730
9393.45.11.128/2793.45.11.129 to 93.45.11.15893.45.11.15930
9493.45.11.160/2793.45.11.161 to 93.45.11.19093.45.11.19130
9593.45.11.192/2793.45.11.193 to 93.45.11.22293.45.11.22330
9693.45.11.224/2793.45.11.225 to 93.45.11.25493.45.11.25530
9793.45.12.0/2793.45.12.1 to 93.45.12.3093.45.12.3130
9893.45.12.32/2793.45.12.33 to 93.45.12.6293.45.12.6330
9993.45.12.64/2793.45.12.65 to 93.45.12.9493.45.12.9530
10093.45.12.96/2793.45.12.97 to 93.45.12.12693.45.12.12730
10193.45.12.128/2793.45.12.129 to 93.45.12.15893.45.12.15930
10293.45.12.160/2793.45.12.161 to 93.45.12.19093.45.12.19130
10393.45.12.192/2793.45.12.193 to 93.45.12.22293.45.12.22330
10493.45.12.224/2793.45.12.225 to 93.45.12.25493.45.12.25530
10593.45.13.0/2793.45.13.1 to 93.45.13.3093.45.13.3130
10693.45.13.32/2793.45.13.33 to 93.45.13.6293.45.13.6330
10793.45.13.64/2793.45.13.65 to 93.45.13.9493.45.13.9530
10893.45.13.96/2793.45.13.97 to 93.45.13.12693.45.13.12730
10993.45.13.128/2793.45.13.129 to 93.45.13.15893.45.13.15930
11093.45.13.160/2793.45.13.161 to 93.45.13.19093.45.13.19130
11193.45.13.192/2793.45.13.193 to 93.45.13.22293.45.13.22330
11293.45.13.224/2793.45.13.225 to 93.45.13.25493.45.13.25530
11393.45.14.0/2793.45.14.1 to 93.45.14.3093.45.14.3130
11493.45.14.32/2793.45.14.33 to 93.45.14.6293.45.14.6330
11593.45.14.64/2793.45.14.65 to 93.45.14.9493.45.14.9530
11693.45.14.96/2793.45.14.97 to 93.45.14.12693.45.14.12730
11793.45.14.128/2793.45.14.129 to 93.45.14.15893.45.14.15930
11893.45.14.160/2793.45.14.161 to 93.45.14.19093.45.14.19130
11993.45.14.192/2793.45.14.193 to 93.45.14.22293.45.14.22330
12093.45.14.224/2793.45.14.225 to 93.45.14.25493.45.14.25530
12193.45.15.0/2793.45.15.1 to 93.45.15.3093.45.15.3130
12293.45.15.32/2793.45.15.33 to 93.45.15.6293.45.15.6330
12393.45.15.64/2793.45.15.65 to 93.45.15.9493.45.15.9530
12493.45.15.96/2793.45.15.97 to 93.45.15.12693.45.15.12730
12593.45.15.128/2793.45.15.129 to 93.45.15.15893.45.15.15930
12693.45.15.160/2793.45.15.161 to 93.45.15.19093.45.15.19130
12793.45.15.192/2793.45.15.193 to 93.45.15.22293.45.15.22330
12893.45.15.224/2793.45.15.225 to 93.45.15.25493.45.15.25530
12993.45.16.0/2793.45.16.1 to 93.45.16.3093.45.16.3130
13093.45.16.32/2793.45.16.33 to 93.45.16.6293.45.16.6330
13193.45.16.64/2793.45.16.65 to 93.45.16.9493.45.16.9530
13293.45.16.96/2793.45.16.97 to 93.45.16.12693.45.16.12730
13393.45.16.128/2793.45.16.129 to 93.45.16.15893.45.16.15930
13493.45.16.160/2793.45.16.161 to 93.45.16.19093.45.16.19130
13593.45.16.192/2793.45.16.193 to 93.45.16.22293.45.16.22330
13693.45.16.224/2793.45.16.225 to 93.45.16.25493.45.16.25530
13793.45.17.0/2793.45.17.1 to 93.45.17.3093.45.17.3130
13893.45.17.32/2793.45.17.33 to 93.45.17.6293.45.17.6330
13993.45.17.64/2793.45.17.65 to 93.45.17.9493.45.17.9530
14093.45.17.96/2793.45.17.97 to 93.45.17.12693.45.17.12730
14193.45.17.128/2793.45.17.129 to 93.45.17.15893.45.17.15930
14293.45.17.160/2793.45.17.161 to 93.45.17.19093.45.17.19130
14393.45.17.192/2793.45.17.193 to 93.45.17.22293.45.17.22330
14493.45.17.224/2793.45.17.225 to 93.45.17.25493.45.17.25530
14593.45.18.0/2793.45.18.1 to 93.45.18.3093.45.18.3130
14693.45.18.32/2793.45.18.33 to 93.45.18.6293.45.18.6330
14793.45.18.64/2793.45.18.65 to 93.45.18.9493.45.18.9530
14893.45.18.96/2793.45.18.97 to 93.45.18.12693.45.18.12730
14993.45.18.128/2793.45.18.129 to 93.45.18.15893.45.18.15930
15093.45.18.160/2793.45.18.161 to 93.45.18.19093.45.18.19130
15193.45.18.192/2793.45.18.193 to 93.45.18.22293.45.18.22330
15293.45.18.224/2793.45.18.225 to 93.45.18.25493.45.18.25530
15393.45.19.0/2793.45.19.1 to 93.45.19.3093.45.19.3130
15493.45.19.32/2793.45.19.33 to 93.45.19.6293.45.19.6330
15593.45.19.64/2793.45.19.65 to 93.45.19.9493.45.19.9530
15693.45.19.96/2793.45.19.97 to 93.45.19.12693.45.19.12730
15793.45.19.128/2793.45.19.129 to 93.45.19.15893.45.19.15930
15893.45.19.160/2793.45.19.161 to 93.45.19.19093.45.19.19130
15993.45.19.192/2793.45.19.193 to 93.45.19.22293.45.19.22330
16093.45.19.224/2793.45.19.225 to 93.45.19.25493.45.19.25530
16193.45.20.0/2793.45.20.1 to 93.45.20.3093.45.20.3130
16293.45.20.32/2793.45.20.33 to 93.45.20.6293.45.20.6330
16393.45.20.64/2793.45.20.65 to 93.45.20.9493.45.20.9530
16493.45.20.96/2793.45.20.97 to 93.45.20.12693.45.20.12730
16593.45.20.128/2793.45.20.129 to 93.45.20.15893.45.20.15930
16693.45.20.160/2793.45.20.161 to 93.45.20.19093.45.20.19130
16793.45.20.192/2793.45.20.193 to 93.45.20.22293.45.20.22330
16893.45.20.224/2793.45.20.225 to 93.45.20.25493.45.20.25530
16993.45.21.0/2793.45.21.1 to 93.45.21.3093.45.21.3130
17093.45.21.32/2793.45.21.33 to 93.45.21.6293.45.21.6330
17193.45.21.64/2793.45.21.65 to 93.45.21.9493.45.21.9530
17293.45.21.96/2793.45.21.97 to 93.45.21.12693.45.21.12730
17393.45.21.128/2793.45.21.129 to 93.45.21.15893.45.21.15930
17493.45.21.160/2793.45.21.161 to 93.45.21.19093.45.21.19130
17593.45.21.192/2793.45.21.193 to 93.45.21.22293.45.21.22330
17693.45.21.224/2793.45.21.225 to 93.45.21.25493.45.21.25530
17793.45.22.0/2793.45.22.1 to 93.45.22.3093.45.22.3130
17893.45.22.32/2793.45.22.33 to 93.45.22.6293.45.22.6330
17993.45.22.64/2793.45.22.65 to 93.45.22.9493.45.22.9530
18093.45.22.96/2793.45.22.97 to 93.45.22.12693.45.22.12730
18193.45.22.128/2793.45.22.129 to 93.45.22.15893.45.22.15930
18293.45.22.160/2793.45.22.161 to 93.45.22.19093.45.22.19130
18393.45.22.192/2793.45.22.193 to 93.45.22.22293.45.22.22330
18493.45.22.224/2793.45.22.225 to 93.45.22.25493.45.22.25530
18593.45.23.0/2793.45.23.1 to 93.45.23.3093.45.23.3130
18693.45.23.32/2793.45.23.33 to 93.45.23.6293.45.23.6330
18793.45.23.64/2793.45.23.65 to 93.45.23.9493.45.23.9530
18893.45.23.96/2793.45.23.97 to 93.45.23.12693.45.23.12730
18993.45.23.128/2793.45.23.129 to 93.45.23.15893.45.23.15930
19093.45.23.160/2793.45.23.161 to 93.45.23.19093.45.23.19130
19193.45.23.192/2793.45.23.193 to 93.45.23.22293.45.23.22330
19293.45.23.224/2793.45.23.225 to 93.45.23.25493.45.23.25530
19393.45.24.0/2793.45.24.1 to 93.45.24.3093.45.24.3130
19493.45.24.32/2793.45.24.33 to 93.45.24.6293.45.24.6330
19593.45.24.64/2793.45.24.65 to 93.45.24.9493.45.24.9530
19693.45.24.96/2793.45.24.97 to 93.45.24.12693.45.24.12730
19793.45.24.128/2793.45.24.129 to 93.45.24.15893.45.24.15930
19893.45.24.160/2793.45.24.161 to 93.45.24.19093.45.24.19130
19993.45.24.192/2793.45.24.193 to 93.45.24.22293.45.24.22330
20093.45.24.224/2793.45.24.225 to 93.45.24.25493.45.24.25530
20193.45.25.0/2793.45.25.1 to 93.45.25.3093.45.25.3130
20293.45.25.32/2793.45.25.33 to 93.45.25.6293.45.25.6330
20393.45.25.64/2793.45.25.65 to 93.45.25.9493.45.25.9530
20493.45.25.96/2793.45.25.97 to 93.45.25.12693.45.25.12730
20593.45.25.128/2793.45.25.129 to 93.45.25.15893.45.25.15930
20693.45.25.160/2793.45.25.161 to 93.45.25.19093.45.25.19130
20793.45.25.192/2793.45.25.193 to 93.45.25.22293.45.25.22330
20893.45.25.224/2793.45.25.225 to 93.45.25.25493.45.25.25530
20993.45.26.0/2793.45.26.1 to 93.45.26.3093.45.26.3130
21093.45.26.32/2793.45.26.33 to 93.45.26.6293.45.26.6330
21193.45.26.64/2793.45.26.65 to 93.45.26.9493.45.26.9530
21293.45.26.96/2793.45.26.97 to 93.45.26.12693.45.26.12730
21393.45.26.128/2793.45.26.129 to 93.45.26.15893.45.26.15930
21493.45.26.160/2793.45.26.161 to 93.45.26.19093.45.26.19130
21593.45.26.192/2793.45.26.193 to 93.45.26.22293.45.26.22330
21693.45.26.224/2793.45.26.225 to 93.45.26.25493.45.26.25530
21793.45.27.0/2793.45.27.1 to 93.45.27.3093.45.27.3130
21893.45.27.32/2793.45.27.33 to 93.45.27.6293.45.27.6330
21993.45.27.64/2793.45.27.65 to 93.45.27.9493.45.27.9530
22093.45.27.96/2793.45.27.97 to 93.45.27.12693.45.27.12730
22193.45.27.128/2793.45.27.129 to 93.45.27.15893.45.27.15930
22293.45.27.160/2793.45.27.161 to 93.45.27.19093.45.27.19130
22393.45.27.192/2793.45.27.193 to 93.45.27.22293.45.27.22330
22493.45.27.224/2793.45.27.225 to 93.45.27.25493.45.27.25530
22593.45.28.0/2793.45.28.1 to 93.45.28.3093.45.28.3130
22693.45.28.32/2793.45.28.33 to 93.45.28.6293.45.28.6330
22793.45.28.64/2793.45.28.65 to 93.45.28.9493.45.28.9530
22893.45.28.96/2793.45.28.97 to 93.45.28.12693.45.28.12730
22993.45.28.128/2793.45.28.129 to 93.45.28.15893.45.28.15930
23093.45.28.160/2793.45.28.161 to 93.45.28.19093.45.28.19130
23193.45.28.192/2793.45.28.193 to 93.45.28.22293.45.28.22330
23293.45.28.224/2793.45.28.225 to 93.45.28.25493.45.28.25530
23393.45.29.0/2793.45.29.1 to 93.45.29.3093.45.29.3130
23493.45.29.32/2793.45.29.33 to 93.45.29.6293.45.29.6330
23593.45.29.64/2793.45.29.65 to 93.45.29.9493.45.29.9530
23693.45.29.96/2793.45.29.97 to 93.45.29.12693.45.29.12730
23793.45.29.128/2793.45.29.129 to 93.45.29.15893.45.29.15930
23893.45.29.160/2793.45.29.161 to 93.45.29.19093.45.29.19130
23993.45.29.192/2793.45.29.193 to 93.45.29.22293.45.29.22330
24093.45.29.224/2793.45.29.225 to 93.45.29.25493.45.29.25530
24193.45.30.0/2793.45.30.1 to 93.45.30.3093.45.30.3130
24293.45.30.32/2793.45.30.33 to 93.45.30.6293.45.30.6330
24393.45.30.64/2793.45.30.65 to 93.45.30.9493.45.30.9530
24493.45.30.96/2793.45.30.97 to 93.45.30.12693.45.30.12730
24593.45.30.128/2793.45.30.129 to 93.45.30.15893.45.30.15930
24693.45.30.160/2793.45.30.161 to 93.45.30.19093.45.30.19130
24793.45.30.192/2793.45.30.193 to 93.45.30.22293.45.30.22330
24893.45.30.224/2793.45.30.225 to 93.45.30.25493.45.30.25530
24993.45.31.0/2793.45.31.1 to 93.45.31.3093.45.31.3130
25093.45.31.32/2793.45.31.33 to 93.45.31.6293.45.31.6330
25193.45.31.64/2793.45.31.65 to 93.45.31.9493.45.31.9530
25293.45.31.96/2793.45.31.97 to 93.45.31.12693.45.31.12730
25393.45.31.128/2793.45.31.129 to 93.45.31.15893.45.31.15930
25493.45.31.160/2793.45.31.161 to 93.45.31.19093.45.31.19130
25593.45.31.192/2793.45.31.193 to 93.45.31.22293.45.31.22330
25693.45.31.224/2793.45.31.225 to 93.45.31.25493.45.31.25530

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.