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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/18
/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 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
193.0.0.0/1893.0.0.1 to 93.0.63.25493.0.63.25516,382
293.0.64.0/1893.0.64.1 to 93.0.127.25493.0.127.25516,382
393.0.128.0/1893.0.128.1 to 93.0.191.25493.0.191.25516,382
493.0.192.0/1893.0.192.1 to 93.0.255.25493.0.255.25516,382
593.1.0.0/1893.1.0.1 to 93.1.63.25493.1.63.25516,382
693.1.64.0/1893.1.64.1 to 93.1.127.25493.1.127.25516,382
793.1.128.0/1893.1.128.1 to 93.1.191.25493.1.191.25516,382
893.1.192.0/1893.1.192.1 to 93.1.255.25493.1.255.25516,382
993.2.0.0/1893.2.0.1 to 93.2.63.25493.2.63.25516,382
1093.2.64.0/1893.2.64.1 to 93.2.127.25493.2.127.25516,382
1193.2.128.0/1893.2.128.1 to 93.2.191.25493.2.191.25516,382
1293.2.192.0/1893.2.192.1 to 93.2.255.25493.2.255.25516,382
1393.3.0.0/1893.3.0.1 to 93.3.63.25493.3.63.25516,382
1493.3.64.0/1893.3.64.1 to 93.3.127.25493.3.127.25516,382
1593.3.128.0/1893.3.128.1 to 93.3.191.25493.3.191.25516,382
1693.3.192.0/1893.3.192.1 to 93.3.255.25493.3.255.25516,382
1793.4.0.0/1893.4.0.1 to 93.4.63.25493.4.63.25516,382
1893.4.64.0/1893.4.64.1 to 93.4.127.25493.4.127.25516,382
1993.4.128.0/1893.4.128.1 to 93.4.191.25493.4.191.25516,382
2093.4.192.0/1893.4.192.1 to 93.4.255.25493.4.255.25516,382
2193.5.0.0/1893.5.0.1 to 93.5.63.25493.5.63.25516,382
2293.5.64.0/1893.5.64.1 to 93.5.127.25493.5.127.25516,382
2393.5.128.0/1893.5.128.1 to 93.5.191.25493.5.191.25516,382
2493.5.192.0/1893.5.192.1 to 93.5.255.25493.5.255.25516,382
2593.6.0.0/1893.6.0.1 to 93.6.63.25493.6.63.25516,382
2693.6.64.0/1893.6.64.1 to 93.6.127.25493.6.127.25516,382
2793.6.128.0/1893.6.128.1 to 93.6.191.25493.6.191.25516,382
2893.6.192.0/1893.6.192.1 to 93.6.255.25493.6.255.25516,382
2993.7.0.0/1893.7.0.1 to 93.7.63.25493.7.63.25516,382
3093.7.64.0/1893.7.64.1 to 93.7.127.25493.7.127.25516,382
3193.7.128.0/1893.7.128.1 to 93.7.191.25493.7.191.25516,382
3293.7.192.0/1893.7.192.1 to 93.7.255.25493.7.255.25516,382
3393.8.0.0/1893.8.0.1 to 93.8.63.25493.8.63.25516,382
3493.8.64.0/1893.8.64.1 to 93.8.127.25493.8.127.25516,382
3593.8.128.0/1893.8.128.1 to 93.8.191.25493.8.191.25516,382
3693.8.192.0/1893.8.192.1 to 93.8.255.25493.8.255.25516,382
3793.9.0.0/1893.9.0.1 to 93.9.63.25493.9.63.25516,382
3893.9.64.0/1893.9.64.1 to 93.9.127.25493.9.127.25516,382
3993.9.128.0/1893.9.128.1 to 93.9.191.25493.9.191.25516,382
4093.9.192.0/1893.9.192.1 to 93.9.255.25493.9.255.25516,382
4193.10.0.0/1893.10.0.1 to 93.10.63.25493.10.63.25516,382
4293.10.64.0/1893.10.64.1 to 93.10.127.25493.10.127.25516,382
4393.10.128.0/1893.10.128.1 to 93.10.191.25493.10.191.25516,382
4493.10.192.0/1893.10.192.1 to 93.10.255.25493.10.255.25516,382
4593.11.0.0/1893.11.0.1 to 93.11.63.25493.11.63.25516,382
4693.11.64.0/1893.11.64.1 to 93.11.127.25493.11.127.25516,382
4793.11.128.0/1893.11.128.1 to 93.11.191.25493.11.191.25516,382
4893.11.192.0/1893.11.192.1 to 93.11.255.25493.11.255.25516,382
4993.12.0.0/1893.12.0.1 to 93.12.63.25493.12.63.25516,382
5093.12.64.0/1893.12.64.1 to 93.12.127.25493.12.127.25516,382
5193.12.128.0/1893.12.128.1 to 93.12.191.25493.12.191.25516,382
5293.12.192.0/1893.12.192.1 to 93.12.255.25493.12.255.25516,382
5393.13.0.0/1893.13.0.1 to 93.13.63.25493.13.63.25516,382
5493.13.64.0/1893.13.64.1 to 93.13.127.25493.13.127.25516,382
5593.13.128.0/1893.13.128.1 to 93.13.191.25493.13.191.25516,382
5693.13.192.0/1893.13.192.1 to 93.13.255.25493.13.255.25516,382
5793.14.0.0/1893.14.0.1 to 93.14.63.25493.14.63.25516,382
5893.14.64.0/1893.14.64.1 to 93.14.127.25493.14.127.25516,382
5993.14.128.0/1893.14.128.1 to 93.14.191.25493.14.191.25516,382
6093.14.192.0/1893.14.192.1 to 93.14.255.25493.14.255.25516,382
6193.15.0.0/1893.15.0.1 to 93.15.63.25493.15.63.25516,382
6293.15.64.0/1893.15.64.1 to 93.15.127.25493.15.127.25516,382
6393.15.128.0/1893.15.128.1 to 93.15.191.25493.15.191.25516,382
6493.15.192.0/1893.15.192.1 to 93.15.255.25493.15.255.25516,382
6593.16.0.0/1893.16.0.1 to 93.16.63.25493.16.63.25516,382
6693.16.64.0/1893.16.64.1 to 93.16.127.25493.16.127.25516,382
6793.16.128.0/1893.16.128.1 to 93.16.191.25493.16.191.25516,382
6893.16.192.0/1893.16.192.1 to 93.16.255.25493.16.255.25516,382
6993.17.0.0/1893.17.0.1 to 93.17.63.25493.17.63.25516,382
7093.17.64.0/1893.17.64.1 to 93.17.127.25493.17.127.25516,382
7193.17.128.0/1893.17.128.1 to 93.17.191.25493.17.191.25516,382
7293.17.192.0/1893.17.192.1 to 93.17.255.25493.17.255.25516,382
7393.18.0.0/1893.18.0.1 to 93.18.63.25493.18.63.25516,382
7493.18.64.0/1893.18.64.1 to 93.18.127.25493.18.127.25516,382
7593.18.128.0/1893.18.128.1 to 93.18.191.25493.18.191.25516,382
7693.18.192.0/1893.18.192.1 to 93.18.255.25493.18.255.25516,382
7793.19.0.0/1893.19.0.1 to 93.19.63.25493.19.63.25516,382
7893.19.64.0/1893.19.64.1 to 93.19.127.25493.19.127.25516,382
7993.19.128.0/1893.19.128.1 to 93.19.191.25493.19.191.25516,382
8093.19.192.0/1893.19.192.1 to 93.19.255.25493.19.255.25516,382
8193.20.0.0/1893.20.0.1 to 93.20.63.25493.20.63.25516,382
8293.20.64.0/1893.20.64.1 to 93.20.127.25493.20.127.25516,382
8393.20.128.0/1893.20.128.1 to 93.20.191.25493.20.191.25516,382
8493.20.192.0/1893.20.192.1 to 93.20.255.25493.20.255.25516,382
8593.21.0.0/1893.21.0.1 to 93.21.63.25493.21.63.25516,382
8693.21.64.0/1893.21.64.1 to 93.21.127.25493.21.127.25516,382
8793.21.128.0/1893.21.128.1 to 93.21.191.25493.21.191.25516,382
8893.21.192.0/1893.21.192.1 to 93.21.255.25493.21.255.25516,382
8993.22.0.0/1893.22.0.1 to 93.22.63.25493.22.63.25516,382
9093.22.64.0/1893.22.64.1 to 93.22.127.25493.22.127.25516,382
9193.22.128.0/1893.22.128.1 to 93.22.191.25493.22.191.25516,382
9293.22.192.0/1893.22.192.1 to 93.22.255.25493.22.255.25516,382
9393.23.0.0/1893.23.0.1 to 93.23.63.25493.23.63.25516,382
9493.23.64.0/1893.23.64.1 to 93.23.127.25493.23.127.25516,382
9593.23.128.0/1893.23.128.1 to 93.23.191.25493.23.191.25516,382
9693.23.192.0/1893.23.192.1 to 93.23.255.25493.23.255.25516,382
9793.24.0.0/1893.24.0.1 to 93.24.63.25493.24.63.25516,382
9893.24.64.0/1893.24.64.1 to 93.24.127.25493.24.127.25516,382
9993.24.128.0/1893.24.128.1 to 93.24.191.25493.24.191.25516,382
10093.24.192.0/1893.24.192.1 to 93.24.255.25493.24.255.25516,382
10193.25.0.0/1893.25.0.1 to 93.25.63.25493.25.63.25516,382
10293.25.64.0/1893.25.64.1 to 93.25.127.25493.25.127.25516,382
10393.25.128.0/1893.25.128.1 to 93.25.191.25493.25.191.25516,382
10493.25.192.0/1893.25.192.1 to 93.25.255.25493.25.255.25516,382
10593.26.0.0/1893.26.0.1 to 93.26.63.25493.26.63.25516,382
10693.26.64.0/1893.26.64.1 to 93.26.127.25493.26.127.25516,382
10793.26.128.0/1893.26.128.1 to 93.26.191.25493.26.191.25516,382
10893.26.192.0/1893.26.192.1 to 93.26.255.25493.26.255.25516,382
10993.27.0.0/1893.27.0.1 to 93.27.63.25493.27.63.25516,382
11093.27.64.0/1893.27.64.1 to 93.27.127.25493.27.127.25516,382
11193.27.128.0/1893.27.128.1 to 93.27.191.25493.27.191.25516,382
11293.27.192.0/1893.27.192.1 to 93.27.255.25493.27.255.25516,382
11393.28.0.0/1893.28.0.1 to 93.28.63.25493.28.63.25516,382
11493.28.64.0/1893.28.64.1 to 93.28.127.25493.28.127.25516,382
11593.28.128.0/1893.28.128.1 to 93.28.191.25493.28.191.25516,382
11693.28.192.0/1893.28.192.1 to 93.28.255.25493.28.255.25516,382
11793.29.0.0/1893.29.0.1 to 93.29.63.25493.29.63.25516,382
11893.29.64.0/1893.29.64.1 to 93.29.127.25493.29.127.25516,382
11993.29.128.0/1893.29.128.1 to 93.29.191.25493.29.191.25516,382
12093.29.192.0/1893.29.192.1 to 93.29.255.25493.29.255.25516,382
12193.30.0.0/1893.30.0.1 to 93.30.63.25493.30.63.25516,382
12293.30.64.0/1893.30.64.1 to 93.30.127.25493.30.127.25516,382
12393.30.128.0/1893.30.128.1 to 93.30.191.25493.30.191.25516,382
12493.30.192.0/1893.30.192.1 to 93.30.255.25493.30.255.25516,382
12593.31.0.0/1893.31.0.1 to 93.31.63.25493.31.63.25516,382
12693.31.64.0/1893.31.64.1 to 93.31.127.25493.31.127.25516,382
12793.31.128.0/1893.31.128.1 to 93.31.191.25493.31.191.25516,382
12893.31.192.0/1893.31.192.1 to 93.31.255.25493.31.255.25516,382
12993.32.0.0/1893.32.0.1 to 93.32.63.25493.32.63.25516,382
13093.32.64.0/1893.32.64.1 to 93.32.127.25493.32.127.25516,382
13193.32.128.0/1893.32.128.1 to 93.32.191.25493.32.191.25516,382
13293.32.192.0/1893.32.192.1 to 93.32.255.25493.32.255.25516,382
13393.33.0.0/1893.33.0.1 to 93.33.63.25493.33.63.25516,382
13493.33.64.0/1893.33.64.1 to 93.33.127.25493.33.127.25516,382
13593.33.128.0/1893.33.128.1 to 93.33.191.25493.33.191.25516,382
13693.33.192.0/1893.33.192.1 to 93.33.255.25493.33.255.25516,382
13793.34.0.0/1893.34.0.1 to 93.34.63.25493.34.63.25516,382
13893.34.64.0/1893.34.64.1 to 93.34.127.25493.34.127.25516,382
13993.34.128.0/1893.34.128.1 to 93.34.191.25493.34.191.25516,382
14093.34.192.0/1893.34.192.1 to 93.34.255.25493.34.255.25516,382
14193.35.0.0/1893.35.0.1 to 93.35.63.25493.35.63.25516,382
14293.35.64.0/1893.35.64.1 to 93.35.127.25493.35.127.25516,382
14393.35.128.0/1893.35.128.1 to 93.35.191.25493.35.191.25516,382
14493.35.192.0/1893.35.192.1 to 93.35.255.25493.35.255.25516,382
14593.36.0.0/1893.36.0.1 to 93.36.63.25493.36.63.25516,382
14693.36.64.0/1893.36.64.1 to 93.36.127.25493.36.127.25516,382
14793.36.128.0/1893.36.128.1 to 93.36.191.25493.36.191.25516,382
14893.36.192.0/1893.36.192.1 to 93.36.255.25493.36.255.25516,382
14993.37.0.0/1893.37.0.1 to 93.37.63.25493.37.63.25516,382
15093.37.64.0/1893.37.64.1 to 93.37.127.25493.37.127.25516,382
15193.37.128.0/1893.37.128.1 to 93.37.191.25493.37.191.25516,382
15293.37.192.0/1893.37.192.1 to 93.37.255.25493.37.255.25516,382
15393.38.0.0/1893.38.0.1 to 93.38.63.25493.38.63.25516,382
15493.38.64.0/1893.38.64.1 to 93.38.127.25493.38.127.25516,382
15593.38.128.0/1893.38.128.1 to 93.38.191.25493.38.191.25516,382
15693.38.192.0/1893.38.192.1 to 93.38.255.25493.38.255.25516,382
15793.39.0.0/1893.39.0.1 to 93.39.63.25493.39.63.25516,382
15893.39.64.0/1893.39.64.1 to 93.39.127.25493.39.127.25516,382
15993.39.128.0/1893.39.128.1 to 93.39.191.25493.39.191.25516,382
16093.39.192.0/1893.39.192.1 to 93.39.255.25493.39.255.25516,382
16193.40.0.0/1893.40.0.1 to 93.40.63.25493.40.63.25516,382
16293.40.64.0/1893.40.64.1 to 93.40.127.25493.40.127.25516,382
16393.40.128.0/1893.40.128.1 to 93.40.191.25493.40.191.25516,382
16493.40.192.0/1893.40.192.1 to 93.40.255.25493.40.255.25516,382
16593.41.0.0/1893.41.0.1 to 93.41.63.25493.41.63.25516,382
16693.41.64.0/1893.41.64.1 to 93.41.127.25493.41.127.25516,382
16793.41.128.0/1893.41.128.1 to 93.41.191.25493.41.191.25516,382
16893.41.192.0/1893.41.192.1 to 93.41.255.25493.41.255.25516,382
16993.42.0.0/1893.42.0.1 to 93.42.63.25493.42.63.25516,382
17093.42.64.0/1893.42.64.1 to 93.42.127.25493.42.127.25516,382
17193.42.128.0/1893.42.128.1 to 93.42.191.25493.42.191.25516,382
17293.42.192.0/1893.42.192.1 to 93.42.255.25493.42.255.25516,382
17393.43.0.0/1893.43.0.1 to 93.43.63.25493.43.63.25516,382
17493.43.64.0/1893.43.64.1 to 93.43.127.25493.43.127.25516,382
17593.43.128.0/1893.43.128.1 to 93.43.191.25493.43.191.25516,382
17693.43.192.0/1893.43.192.1 to 93.43.255.25493.43.255.25516,382
17793.44.0.0/1893.44.0.1 to 93.44.63.25493.44.63.25516,382
17893.44.64.0/1893.44.64.1 to 93.44.127.25493.44.127.25516,382
17993.44.128.0/1893.44.128.1 to 93.44.191.25493.44.191.25516,382
18093.44.192.0/1893.44.192.1 to 93.44.255.25493.44.255.25516,382
18193.45.0.0/1893.45.0.1 to 93.45.63.25493.45.63.25516,382
18293.45.64.0/1893.45.64.1 to 93.45.127.25493.45.127.25516,382
18393.45.128.0/1893.45.128.1 to 93.45.191.25493.45.191.25516,382
18493.45.192.0/1893.45.192.1 to 93.45.255.25493.45.255.25516,382
18593.46.0.0/1893.46.0.1 to 93.46.63.25493.46.63.25516,382
18693.46.64.0/1893.46.64.1 to 93.46.127.25493.46.127.25516,382
18793.46.128.0/1893.46.128.1 to 93.46.191.25493.46.191.25516,382
18893.46.192.0/1893.46.192.1 to 93.46.255.25493.46.255.25516,382
18993.47.0.0/1893.47.0.1 to 93.47.63.25493.47.63.25516,382
19093.47.64.0/1893.47.64.1 to 93.47.127.25493.47.127.25516,382
19193.47.128.0/1893.47.128.1 to 93.47.191.25493.47.191.25516,382
19293.47.192.0/1893.47.192.1 to 93.47.255.25493.47.255.25516,382
19393.48.0.0/1893.48.0.1 to 93.48.63.25493.48.63.25516,382
19493.48.64.0/1893.48.64.1 to 93.48.127.25493.48.127.25516,382
19593.48.128.0/1893.48.128.1 to 93.48.191.25493.48.191.25516,382
19693.48.192.0/1893.48.192.1 to 93.48.255.25493.48.255.25516,382
19793.49.0.0/1893.49.0.1 to 93.49.63.25493.49.63.25516,382
19893.49.64.0/1893.49.64.1 to 93.49.127.25493.49.127.25516,382
19993.49.128.0/1893.49.128.1 to 93.49.191.25493.49.191.25516,382
20093.49.192.0/1893.49.192.1 to 93.49.255.25493.49.255.25516,382
20193.50.0.0/1893.50.0.1 to 93.50.63.25493.50.63.25516,382
20293.50.64.0/1893.50.64.1 to 93.50.127.25493.50.127.25516,382
20393.50.128.0/1893.50.128.1 to 93.50.191.25493.50.191.25516,382
20493.50.192.0/1893.50.192.1 to 93.50.255.25493.50.255.25516,382
20593.51.0.0/1893.51.0.1 to 93.51.63.25493.51.63.25516,382
20693.51.64.0/1893.51.64.1 to 93.51.127.25493.51.127.25516,382
20793.51.128.0/1893.51.128.1 to 93.51.191.25493.51.191.25516,382
20893.51.192.0/1893.51.192.1 to 93.51.255.25493.51.255.25516,382
20993.52.0.0/1893.52.0.1 to 93.52.63.25493.52.63.25516,382
21093.52.64.0/1893.52.64.1 to 93.52.127.25493.52.127.25516,382
21193.52.128.0/1893.52.128.1 to 93.52.191.25493.52.191.25516,382
21293.52.192.0/1893.52.192.1 to 93.52.255.25493.52.255.25516,382
21393.53.0.0/1893.53.0.1 to 93.53.63.25493.53.63.25516,382
21493.53.64.0/1893.53.64.1 to 93.53.127.25493.53.127.25516,382
21593.53.128.0/1893.53.128.1 to 93.53.191.25493.53.191.25516,382
21693.53.192.0/1893.53.192.1 to 93.53.255.25493.53.255.25516,382
21793.54.0.0/1893.54.0.1 to 93.54.63.25493.54.63.25516,382
21893.54.64.0/1893.54.64.1 to 93.54.127.25493.54.127.25516,382
21993.54.128.0/1893.54.128.1 to 93.54.191.25493.54.191.25516,382
22093.54.192.0/1893.54.192.1 to 93.54.255.25493.54.255.25516,382
22193.55.0.0/1893.55.0.1 to 93.55.63.25493.55.63.25516,382
22293.55.64.0/1893.55.64.1 to 93.55.127.25493.55.127.25516,382
22393.55.128.0/1893.55.128.1 to 93.55.191.25493.55.191.25516,382
22493.55.192.0/1893.55.192.1 to 93.55.255.25493.55.255.25516,382
22593.56.0.0/1893.56.0.1 to 93.56.63.25493.56.63.25516,382
22693.56.64.0/1893.56.64.1 to 93.56.127.25493.56.127.25516,382
22793.56.128.0/1893.56.128.1 to 93.56.191.25493.56.191.25516,382
22893.56.192.0/1893.56.192.1 to 93.56.255.25493.56.255.25516,382
22993.57.0.0/1893.57.0.1 to 93.57.63.25493.57.63.25516,382
23093.57.64.0/1893.57.64.1 to 93.57.127.25493.57.127.25516,382
23193.57.128.0/1893.57.128.1 to 93.57.191.25493.57.191.25516,382
23293.57.192.0/1893.57.192.1 to 93.57.255.25493.57.255.25516,382
23393.58.0.0/1893.58.0.1 to 93.58.63.25493.58.63.25516,382
23493.58.64.0/1893.58.64.1 to 93.58.127.25493.58.127.25516,382
23593.58.128.0/1893.58.128.1 to 93.58.191.25493.58.191.25516,382
23693.58.192.0/1893.58.192.1 to 93.58.255.25493.58.255.25516,382
23793.59.0.0/1893.59.0.1 to 93.59.63.25493.59.63.25516,382
23893.59.64.0/1893.59.64.1 to 93.59.127.25493.59.127.25516,382
23993.59.128.0/1893.59.128.1 to 93.59.191.25493.59.191.25516,382
24093.59.192.0/1893.59.192.1 to 93.59.255.25493.59.255.25516,382
24193.60.0.0/1893.60.0.1 to 93.60.63.25493.60.63.25516,382
24293.60.64.0/1893.60.64.1 to 93.60.127.25493.60.127.25516,382
24393.60.128.0/1893.60.128.1 to 93.60.191.25493.60.191.25516,382
24493.60.192.0/1893.60.192.1 to 93.60.255.25493.60.255.25516,382
24593.61.0.0/1893.61.0.1 to 93.61.63.25493.61.63.25516,382
24693.61.64.0/1893.61.64.1 to 93.61.127.25493.61.127.25516,382
24793.61.128.0/1893.61.128.1 to 93.61.191.25493.61.191.25516,382
24893.61.192.0/1893.61.192.1 to 93.61.255.25493.61.255.25516,382
24993.62.0.0/1893.62.0.1 to 93.62.63.25493.62.63.25516,382
25093.62.64.0/1893.62.64.1 to 93.62.127.25493.62.127.25516,382
25193.62.128.0/1893.62.128.1 to 93.62.191.25493.62.191.25516,382
25293.62.192.0/1893.62.192.1 to 93.62.255.25493.62.255.25516,382
25393.63.0.0/1893.63.0.1 to 93.63.63.25493.63.63.25516,382
25493.63.64.0/1893.63.64.1 to 93.63.127.25493.63.127.25516,382
25593.63.128.0/1893.63.128.1 to 93.63.191.25493.63.191.25516,382
25693.63.192.0/1893.63.192.1 to 93.63.255.25493.63.255.25516,382

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.