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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.

Network93.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
93.0.0.0
Broadcast address
93.255.255.255
First usable
93.0.0.1
Last usable
93.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 5D000000 · Integer 1560281088 to 1577058303
Reverse DNS zone
93.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011101..00000000.00000000.0000000093.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01011101..00000000.00000000.0000000093.0.0.0
Broadcast01011101..11111111.11111111.1111111193.255.255.255
Split into smaller subnets/19
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

93.0.0.0/8 makes 2,048 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
193.0.0.0/1993.0.0.1 to 93.0.31.25493.0.31.2558,190
293.0.32.0/1993.0.32.1 to 93.0.63.25493.0.63.2558,190
393.0.64.0/1993.0.64.1 to 93.0.95.25493.0.95.2558,190
493.0.96.0/1993.0.96.1 to 93.0.127.25493.0.127.2558,190
593.0.128.0/1993.0.128.1 to 93.0.159.25493.0.159.2558,190
693.0.160.0/1993.0.160.1 to 93.0.191.25493.0.191.2558,190
793.0.192.0/1993.0.192.1 to 93.0.223.25493.0.223.2558,190
893.0.224.0/1993.0.224.1 to 93.0.255.25493.0.255.2558,190
993.1.0.0/1993.1.0.1 to 93.1.31.25493.1.31.2558,190
1093.1.32.0/1993.1.32.1 to 93.1.63.25493.1.63.2558,190
1193.1.64.0/1993.1.64.1 to 93.1.95.25493.1.95.2558,190
1293.1.96.0/1993.1.96.1 to 93.1.127.25493.1.127.2558,190
1393.1.128.0/1993.1.128.1 to 93.1.159.25493.1.159.2558,190
1493.1.160.0/1993.1.160.1 to 93.1.191.25493.1.191.2558,190
1593.1.192.0/1993.1.192.1 to 93.1.223.25493.1.223.2558,190
1693.1.224.0/1993.1.224.1 to 93.1.255.25493.1.255.2558,190
1793.2.0.0/1993.2.0.1 to 93.2.31.25493.2.31.2558,190
1893.2.32.0/1993.2.32.1 to 93.2.63.25493.2.63.2558,190
1993.2.64.0/1993.2.64.1 to 93.2.95.25493.2.95.2558,190
2093.2.96.0/1993.2.96.1 to 93.2.127.25493.2.127.2558,190
2193.2.128.0/1993.2.128.1 to 93.2.159.25493.2.159.2558,190
2293.2.160.0/1993.2.160.1 to 93.2.191.25493.2.191.2558,190
2393.2.192.0/1993.2.192.1 to 93.2.223.25493.2.223.2558,190
2493.2.224.0/1993.2.224.1 to 93.2.255.25493.2.255.2558,190
2593.3.0.0/1993.3.0.1 to 93.3.31.25493.3.31.2558,190
2693.3.32.0/1993.3.32.1 to 93.3.63.25493.3.63.2558,190
2793.3.64.0/1993.3.64.1 to 93.3.95.25493.3.95.2558,190
2893.3.96.0/1993.3.96.1 to 93.3.127.25493.3.127.2558,190
2993.3.128.0/1993.3.128.1 to 93.3.159.25493.3.159.2558,190
3093.3.160.0/1993.3.160.1 to 93.3.191.25493.3.191.2558,190
3193.3.192.0/1993.3.192.1 to 93.3.223.25493.3.223.2558,190
3293.3.224.0/1993.3.224.1 to 93.3.255.25493.3.255.2558,190
3393.4.0.0/1993.4.0.1 to 93.4.31.25493.4.31.2558,190
3493.4.32.0/1993.4.32.1 to 93.4.63.25493.4.63.2558,190
3593.4.64.0/1993.4.64.1 to 93.4.95.25493.4.95.2558,190
3693.4.96.0/1993.4.96.1 to 93.4.127.25493.4.127.2558,190
3793.4.128.0/1993.4.128.1 to 93.4.159.25493.4.159.2558,190
3893.4.160.0/1993.4.160.1 to 93.4.191.25493.4.191.2558,190
3993.4.192.0/1993.4.192.1 to 93.4.223.25493.4.223.2558,190
4093.4.224.0/1993.4.224.1 to 93.4.255.25493.4.255.2558,190
4193.5.0.0/1993.5.0.1 to 93.5.31.25493.5.31.2558,190
4293.5.32.0/1993.5.32.1 to 93.5.63.25493.5.63.2558,190
4393.5.64.0/1993.5.64.1 to 93.5.95.25493.5.95.2558,190
4493.5.96.0/1993.5.96.1 to 93.5.127.25493.5.127.2558,190
4593.5.128.0/1993.5.128.1 to 93.5.159.25493.5.159.2558,190
4693.5.160.0/1993.5.160.1 to 93.5.191.25493.5.191.2558,190
4793.5.192.0/1993.5.192.1 to 93.5.223.25493.5.223.2558,190
4893.5.224.0/1993.5.224.1 to 93.5.255.25493.5.255.2558,190
4993.6.0.0/1993.6.0.1 to 93.6.31.25493.6.31.2558,190
5093.6.32.0/1993.6.32.1 to 93.6.63.25493.6.63.2558,190
5193.6.64.0/1993.6.64.1 to 93.6.95.25493.6.95.2558,190
5293.6.96.0/1993.6.96.1 to 93.6.127.25493.6.127.2558,190
5393.6.128.0/1993.6.128.1 to 93.6.159.25493.6.159.2558,190
5493.6.160.0/1993.6.160.1 to 93.6.191.25493.6.191.2558,190
5593.6.192.0/1993.6.192.1 to 93.6.223.25493.6.223.2558,190
5693.6.224.0/1993.6.224.1 to 93.6.255.25493.6.255.2558,190
5793.7.0.0/1993.7.0.1 to 93.7.31.25493.7.31.2558,190
5893.7.32.0/1993.7.32.1 to 93.7.63.25493.7.63.2558,190
5993.7.64.0/1993.7.64.1 to 93.7.95.25493.7.95.2558,190
6093.7.96.0/1993.7.96.1 to 93.7.127.25493.7.127.2558,190
6193.7.128.0/1993.7.128.1 to 93.7.159.25493.7.159.2558,190
6293.7.160.0/1993.7.160.1 to 93.7.191.25493.7.191.2558,190
6393.7.192.0/1993.7.192.1 to 93.7.223.25493.7.223.2558,190
6493.7.224.0/1993.7.224.1 to 93.7.255.25493.7.255.2558,190
6593.8.0.0/1993.8.0.1 to 93.8.31.25493.8.31.2558,190
6693.8.32.0/1993.8.32.1 to 93.8.63.25493.8.63.2558,190
6793.8.64.0/1993.8.64.1 to 93.8.95.25493.8.95.2558,190
6893.8.96.0/1993.8.96.1 to 93.8.127.25493.8.127.2558,190
6993.8.128.0/1993.8.128.1 to 93.8.159.25493.8.159.2558,190
7093.8.160.0/1993.8.160.1 to 93.8.191.25493.8.191.2558,190
7193.8.192.0/1993.8.192.1 to 93.8.223.25493.8.223.2558,190
7293.8.224.0/1993.8.224.1 to 93.8.255.25493.8.255.2558,190
7393.9.0.0/1993.9.0.1 to 93.9.31.25493.9.31.2558,190
7493.9.32.0/1993.9.32.1 to 93.9.63.25493.9.63.2558,190
7593.9.64.0/1993.9.64.1 to 93.9.95.25493.9.95.2558,190
7693.9.96.0/1993.9.96.1 to 93.9.127.25493.9.127.2558,190
7793.9.128.0/1993.9.128.1 to 93.9.159.25493.9.159.2558,190
7893.9.160.0/1993.9.160.1 to 93.9.191.25493.9.191.2558,190
7993.9.192.0/1993.9.192.1 to 93.9.223.25493.9.223.2558,190
8093.9.224.0/1993.9.224.1 to 93.9.255.25493.9.255.2558,190
8193.10.0.0/1993.10.0.1 to 93.10.31.25493.10.31.2558,190
8293.10.32.0/1993.10.32.1 to 93.10.63.25493.10.63.2558,190
8393.10.64.0/1993.10.64.1 to 93.10.95.25493.10.95.2558,190
8493.10.96.0/1993.10.96.1 to 93.10.127.25493.10.127.2558,190
8593.10.128.0/1993.10.128.1 to 93.10.159.25493.10.159.2558,190
8693.10.160.0/1993.10.160.1 to 93.10.191.25493.10.191.2558,190
8793.10.192.0/1993.10.192.1 to 93.10.223.25493.10.223.2558,190
8893.10.224.0/1993.10.224.1 to 93.10.255.25493.10.255.2558,190
8993.11.0.0/1993.11.0.1 to 93.11.31.25493.11.31.2558,190
9093.11.32.0/1993.11.32.1 to 93.11.63.25493.11.63.2558,190
9193.11.64.0/1993.11.64.1 to 93.11.95.25493.11.95.2558,190
9293.11.96.0/1993.11.96.1 to 93.11.127.25493.11.127.2558,190
9393.11.128.0/1993.11.128.1 to 93.11.159.25493.11.159.2558,190
9493.11.160.0/1993.11.160.1 to 93.11.191.25493.11.191.2558,190
9593.11.192.0/1993.11.192.1 to 93.11.223.25493.11.223.2558,190
9693.11.224.0/1993.11.224.1 to 93.11.255.25493.11.255.2558,190
9793.12.0.0/1993.12.0.1 to 93.12.31.25493.12.31.2558,190
9893.12.32.0/1993.12.32.1 to 93.12.63.25493.12.63.2558,190
9993.12.64.0/1993.12.64.1 to 93.12.95.25493.12.95.2558,190
10093.12.96.0/1993.12.96.1 to 93.12.127.25493.12.127.2558,190
10193.12.128.0/1993.12.128.1 to 93.12.159.25493.12.159.2558,190
10293.12.160.0/1993.12.160.1 to 93.12.191.25493.12.191.2558,190
10393.12.192.0/1993.12.192.1 to 93.12.223.25493.12.223.2558,190
10493.12.224.0/1993.12.224.1 to 93.12.255.25493.12.255.2558,190
10593.13.0.0/1993.13.0.1 to 93.13.31.25493.13.31.2558,190
10693.13.32.0/1993.13.32.1 to 93.13.63.25493.13.63.2558,190
10793.13.64.0/1993.13.64.1 to 93.13.95.25493.13.95.2558,190
10893.13.96.0/1993.13.96.1 to 93.13.127.25493.13.127.2558,190
10993.13.128.0/1993.13.128.1 to 93.13.159.25493.13.159.2558,190
11093.13.160.0/1993.13.160.1 to 93.13.191.25493.13.191.2558,190
11193.13.192.0/1993.13.192.1 to 93.13.223.25493.13.223.2558,190
11293.13.224.0/1993.13.224.1 to 93.13.255.25493.13.255.2558,190
11393.14.0.0/1993.14.0.1 to 93.14.31.25493.14.31.2558,190
11493.14.32.0/1993.14.32.1 to 93.14.63.25493.14.63.2558,190
11593.14.64.0/1993.14.64.1 to 93.14.95.25493.14.95.2558,190
11693.14.96.0/1993.14.96.1 to 93.14.127.25493.14.127.2558,190
11793.14.128.0/1993.14.128.1 to 93.14.159.25493.14.159.2558,190
11893.14.160.0/1993.14.160.1 to 93.14.191.25493.14.191.2558,190
11993.14.192.0/1993.14.192.1 to 93.14.223.25493.14.223.2558,190
12093.14.224.0/1993.14.224.1 to 93.14.255.25493.14.255.2558,190
12193.15.0.0/1993.15.0.1 to 93.15.31.25493.15.31.2558,190
12293.15.32.0/1993.15.32.1 to 93.15.63.25493.15.63.2558,190
12393.15.64.0/1993.15.64.1 to 93.15.95.25493.15.95.2558,190
12493.15.96.0/1993.15.96.1 to 93.15.127.25493.15.127.2558,190
12593.15.128.0/1993.15.128.1 to 93.15.159.25493.15.159.2558,190
12693.15.160.0/1993.15.160.1 to 93.15.191.25493.15.191.2558,190
12793.15.192.0/1993.15.192.1 to 93.15.223.25493.15.223.2558,190
12893.15.224.0/1993.15.224.1 to 93.15.255.25493.15.255.2558,190
12993.16.0.0/1993.16.0.1 to 93.16.31.25493.16.31.2558,190
13093.16.32.0/1993.16.32.1 to 93.16.63.25493.16.63.2558,190
13193.16.64.0/1993.16.64.1 to 93.16.95.25493.16.95.2558,190
13293.16.96.0/1993.16.96.1 to 93.16.127.25493.16.127.2558,190
13393.16.128.0/1993.16.128.1 to 93.16.159.25493.16.159.2558,190
13493.16.160.0/1993.16.160.1 to 93.16.191.25493.16.191.2558,190
13593.16.192.0/1993.16.192.1 to 93.16.223.25493.16.223.2558,190
13693.16.224.0/1993.16.224.1 to 93.16.255.25493.16.255.2558,190
13793.17.0.0/1993.17.0.1 to 93.17.31.25493.17.31.2558,190
13893.17.32.0/1993.17.32.1 to 93.17.63.25493.17.63.2558,190
13993.17.64.0/1993.17.64.1 to 93.17.95.25493.17.95.2558,190
14093.17.96.0/1993.17.96.1 to 93.17.127.25493.17.127.2558,190
14193.17.128.0/1993.17.128.1 to 93.17.159.25493.17.159.2558,190
14293.17.160.0/1993.17.160.1 to 93.17.191.25493.17.191.2558,190
14393.17.192.0/1993.17.192.1 to 93.17.223.25493.17.223.2558,190
14493.17.224.0/1993.17.224.1 to 93.17.255.25493.17.255.2558,190
14593.18.0.0/1993.18.0.1 to 93.18.31.25493.18.31.2558,190
14693.18.32.0/1993.18.32.1 to 93.18.63.25493.18.63.2558,190
14793.18.64.0/1993.18.64.1 to 93.18.95.25493.18.95.2558,190
14893.18.96.0/1993.18.96.1 to 93.18.127.25493.18.127.2558,190
14993.18.128.0/1993.18.128.1 to 93.18.159.25493.18.159.2558,190
15093.18.160.0/1993.18.160.1 to 93.18.191.25493.18.191.2558,190
15193.18.192.0/1993.18.192.1 to 93.18.223.25493.18.223.2558,190
15293.18.224.0/1993.18.224.1 to 93.18.255.25493.18.255.2558,190
15393.19.0.0/1993.19.0.1 to 93.19.31.25493.19.31.2558,190
15493.19.32.0/1993.19.32.1 to 93.19.63.25493.19.63.2558,190
15593.19.64.0/1993.19.64.1 to 93.19.95.25493.19.95.2558,190
15693.19.96.0/1993.19.96.1 to 93.19.127.25493.19.127.2558,190
15793.19.128.0/1993.19.128.1 to 93.19.159.25493.19.159.2558,190
15893.19.160.0/1993.19.160.1 to 93.19.191.25493.19.191.2558,190
15993.19.192.0/1993.19.192.1 to 93.19.223.25493.19.223.2558,190
16093.19.224.0/1993.19.224.1 to 93.19.255.25493.19.255.2558,190
16193.20.0.0/1993.20.0.1 to 93.20.31.25493.20.31.2558,190
16293.20.32.0/1993.20.32.1 to 93.20.63.25493.20.63.2558,190
16393.20.64.0/1993.20.64.1 to 93.20.95.25493.20.95.2558,190
16493.20.96.0/1993.20.96.1 to 93.20.127.25493.20.127.2558,190
16593.20.128.0/1993.20.128.1 to 93.20.159.25493.20.159.2558,190
16693.20.160.0/1993.20.160.1 to 93.20.191.25493.20.191.2558,190
16793.20.192.0/1993.20.192.1 to 93.20.223.25493.20.223.2558,190
16893.20.224.0/1993.20.224.1 to 93.20.255.25493.20.255.2558,190
16993.21.0.0/1993.21.0.1 to 93.21.31.25493.21.31.2558,190
17093.21.32.0/1993.21.32.1 to 93.21.63.25493.21.63.2558,190
17193.21.64.0/1993.21.64.1 to 93.21.95.25493.21.95.2558,190
17293.21.96.0/1993.21.96.1 to 93.21.127.25493.21.127.2558,190
17393.21.128.0/1993.21.128.1 to 93.21.159.25493.21.159.2558,190
17493.21.160.0/1993.21.160.1 to 93.21.191.25493.21.191.2558,190
17593.21.192.0/1993.21.192.1 to 93.21.223.25493.21.223.2558,190
17693.21.224.0/1993.21.224.1 to 93.21.255.25493.21.255.2558,190
17793.22.0.0/1993.22.0.1 to 93.22.31.25493.22.31.2558,190
17893.22.32.0/1993.22.32.1 to 93.22.63.25493.22.63.2558,190
17993.22.64.0/1993.22.64.1 to 93.22.95.25493.22.95.2558,190
18093.22.96.0/1993.22.96.1 to 93.22.127.25493.22.127.2558,190
18193.22.128.0/1993.22.128.1 to 93.22.159.25493.22.159.2558,190
18293.22.160.0/1993.22.160.1 to 93.22.191.25493.22.191.2558,190
18393.22.192.0/1993.22.192.1 to 93.22.223.25493.22.223.2558,190
18493.22.224.0/1993.22.224.1 to 93.22.255.25493.22.255.2558,190
18593.23.0.0/1993.23.0.1 to 93.23.31.25493.23.31.2558,190
18693.23.32.0/1993.23.32.1 to 93.23.63.25493.23.63.2558,190
18793.23.64.0/1993.23.64.1 to 93.23.95.25493.23.95.2558,190
18893.23.96.0/1993.23.96.1 to 93.23.127.25493.23.127.2558,190
18993.23.128.0/1993.23.128.1 to 93.23.159.25493.23.159.2558,190
19093.23.160.0/1993.23.160.1 to 93.23.191.25493.23.191.2558,190
19193.23.192.0/1993.23.192.1 to 93.23.223.25493.23.223.2558,190
19293.23.224.0/1993.23.224.1 to 93.23.255.25493.23.255.2558,190
19393.24.0.0/1993.24.0.1 to 93.24.31.25493.24.31.2558,190
19493.24.32.0/1993.24.32.1 to 93.24.63.25493.24.63.2558,190
19593.24.64.0/1993.24.64.1 to 93.24.95.25493.24.95.2558,190
19693.24.96.0/1993.24.96.1 to 93.24.127.25493.24.127.2558,190
19793.24.128.0/1993.24.128.1 to 93.24.159.25493.24.159.2558,190
19893.24.160.0/1993.24.160.1 to 93.24.191.25493.24.191.2558,190
19993.24.192.0/1993.24.192.1 to 93.24.223.25493.24.223.2558,190
20093.24.224.0/1993.24.224.1 to 93.24.255.25493.24.255.2558,190
20193.25.0.0/1993.25.0.1 to 93.25.31.25493.25.31.2558,190
20293.25.32.0/1993.25.32.1 to 93.25.63.25493.25.63.2558,190
20393.25.64.0/1993.25.64.1 to 93.25.95.25493.25.95.2558,190
20493.25.96.0/1993.25.96.1 to 93.25.127.25493.25.127.2558,190
20593.25.128.0/1993.25.128.1 to 93.25.159.25493.25.159.2558,190
20693.25.160.0/1993.25.160.1 to 93.25.191.25493.25.191.2558,190
20793.25.192.0/1993.25.192.1 to 93.25.223.25493.25.223.2558,190
20893.25.224.0/1993.25.224.1 to 93.25.255.25493.25.255.2558,190
20993.26.0.0/1993.26.0.1 to 93.26.31.25493.26.31.2558,190
21093.26.32.0/1993.26.32.1 to 93.26.63.25493.26.63.2558,190
21193.26.64.0/1993.26.64.1 to 93.26.95.25493.26.95.2558,190
21293.26.96.0/1993.26.96.1 to 93.26.127.25493.26.127.2558,190
21393.26.128.0/1993.26.128.1 to 93.26.159.25493.26.159.2558,190
21493.26.160.0/1993.26.160.1 to 93.26.191.25493.26.191.2558,190
21593.26.192.0/1993.26.192.1 to 93.26.223.25493.26.223.2558,190
21693.26.224.0/1993.26.224.1 to 93.26.255.25493.26.255.2558,190
21793.27.0.0/1993.27.0.1 to 93.27.31.25493.27.31.2558,190
21893.27.32.0/1993.27.32.1 to 93.27.63.25493.27.63.2558,190
21993.27.64.0/1993.27.64.1 to 93.27.95.25493.27.95.2558,190
22093.27.96.0/1993.27.96.1 to 93.27.127.25493.27.127.2558,190
22193.27.128.0/1993.27.128.1 to 93.27.159.25493.27.159.2558,190
22293.27.160.0/1993.27.160.1 to 93.27.191.25493.27.191.2558,190
22393.27.192.0/1993.27.192.1 to 93.27.223.25493.27.223.2558,190
22493.27.224.0/1993.27.224.1 to 93.27.255.25493.27.255.2558,190
22593.28.0.0/1993.28.0.1 to 93.28.31.25493.28.31.2558,190
22693.28.32.0/1993.28.32.1 to 93.28.63.25493.28.63.2558,190
22793.28.64.0/1993.28.64.1 to 93.28.95.25493.28.95.2558,190
22893.28.96.0/1993.28.96.1 to 93.28.127.25493.28.127.2558,190
22993.28.128.0/1993.28.128.1 to 93.28.159.25493.28.159.2558,190
23093.28.160.0/1993.28.160.1 to 93.28.191.25493.28.191.2558,190
23193.28.192.0/1993.28.192.1 to 93.28.223.25493.28.223.2558,190
23293.28.224.0/1993.28.224.1 to 93.28.255.25493.28.255.2558,190
23393.29.0.0/1993.29.0.1 to 93.29.31.25493.29.31.2558,190
23493.29.32.0/1993.29.32.1 to 93.29.63.25493.29.63.2558,190
23593.29.64.0/1993.29.64.1 to 93.29.95.25493.29.95.2558,190
23693.29.96.0/1993.29.96.1 to 93.29.127.25493.29.127.2558,190
23793.29.128.0/1993.29.128.1 to 93.29.159.25493.29.159.2558,190
23893.29.160.0/1993.29.160.1 to 93.29.191.25493.29.191.2558,190
23993.29.192.0/1993.29.192.1 to 93.29.223.25493.29.223.2558,190
24093.29.224.0/1993.29.224.1 to 93.29.255.25493.29.255.2558,190
24193.30.0.0/1993.30.0.1 to 93.30.31.25493.30.31.2558,190
24293.30.32.0/1993.30.32.1 to 93.30.63.25493.30.63.2558,190
24393.30.64.0/1993.30.64.1 to 93.30.95.25493.30.95.2558,190
24493.30.96.0/1993.30.96.1 to 93.30.127.25493.30.127.2558,190
24593.30.128.0/1993.30.128.1 to 93.30.159.25493.30.159.2558,190
24693.30.160.0/1993.30.160.1 to 93.30.191.25493.30.191.2558,190
24793.30.192.0/1993.30.192.1 to 93.30.223.25493.30.223.2558,190
24893.30.224.0/1993.30.224.1 to 93.30.255.25493.30.255.2558,190
24993.31.0.0/1993.31.0.1 to 93.31.31.25493.31.31.2558,190
25093.31.32.0/1993.31.32.1 to 93.31.63.25493.31.63.2558,190
25193.31.64.0/1993.31.64.1 to 93.31.95.25493.31.95.2558,190
25293.31.96.0/1993.31.96.1 to 93.31.127.25493.31.127.2558,190
25393.31.128.0/1993.31.128.1 to 93.31.159.25493.31.159.2558,190
25493.31.160.0/1993.31.160.1 to 93.31.191.25493.31.191.2558,190
25593.31.192.0/1993.31.192.1 to 93.31.223.25493.31.223.2558,190
25693.31.224.0/1993.31.224.1 to 93.31.255.25493.31.255.2558,190

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.