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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.

Network93.64.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
93.64.0.0
Broadcast address
93.71.255.255
First usable
93.64.0.1
Last usable
93.71.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 5D400000 · Integer 1564475392 to 1564999679
Reverse DNS zones
64.93.in-addr.arpa
65.93.in-addr.arpa
66.93.in-addr.arpa
67.93.in-addr.arpa
68.93.in-addr.arpa
69.93.in-addr.arpa
70.93.in-addr.arpa
71.93.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011101.01000000.00000000.0000000093.64.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network01011101.01000000.00000000.0000000093.64.0.0
Broadcast01011101.01000111.11111111.1111111193.71.255.255
Split into smaller subnets/22
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

93.64.0.0/13 makes 512 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
193.64.0.0/2293.64.0.1 to 93.64.3.25493.64.3.2551,022
293.64.4.0/2293.64.4.1 to 93.64.7.25493.64.7.2551,022
393.64.8.0/2293.64.8.1 to 93.64.11.25493.64.11.2551,022
493.64.12.0/2293.64.12.1 to 93.64.15.25493.64.15.2551,022
593.64.16.0/2293.64.16.1 to 93.64.19.25493.64.19.2551,022
693.64.20.0/2293.64.20.1 to 93.64.23.25493.64.23.2551,022
793.64.24.0/2293.64.24.1 to 93.64.27.25493.64.27.2551,022
893.64.28.0/2293.64.28.1 to 93.64.31.25493.64.31.2551,022
993.64.32.0/2293.64.32.1 to 93.64.35.25493.64.35.2551,022
1093.64.36.0/2293.64.36.1 to 93.64.39.25493.64.39.2551,022
1193.64.40.0/2293.64.40.1 to 93.64.43.25493.64.43.2551,022
1293.64.44.0/2293.64.44.1 to 93.64.47.25493.64.47.2551,022
1393.64.48.0/2293.64.48.1 to 93.64.51.25493.64.51.2551,022
1493.64.52.0/2293.64.52.1 to 93.64.55.25493.64.55.2551,022
1593.64.56.0/2293.64.56.1 to 93.64.59.25493.64.59.2551,022
1693.64.60.0/2293.64.60.1 to 93.64.63.25493.64.63.2551,022
1793.64.64.0/2293.64.64.1 to 93.64.67.25493.64.67.2551,022
1893.64.68.0/2293.64.68.1 to 93.64.71.25493.64.71.2551,022
1993.64.72.0/2293.64.72.1 to 93.64.75.25493.64.75.2551,022
2093.64.76.0/2293.64.76.1 to 93.64.79.25493.64.79.2551,022
2193.64.80.0/2293.64.80.1 to 93.64.83.25493.64.83.2551,022
2293.64.84.0/2293.64.84.1 to 93.64.87.25493.64.87.2551,022
2393.64.88.0/2293.64.88.1 to 93.64.91.25493.64.91.2551,022
2493.64.92.0/2293.64.92.1 to 93.64.95.25493.64.95.2551,022
2593.64.96.0/2293.64.96.1 to 93.64.99.25493.64.99.2551,022
2693.64.100.0/2293.64.100.1 to 93.64.103.25493.64.103.2551,022
2793.64.104.0/2293.64.104.1 to 93.64.107.25493.64.107.2551,022
2893.64.108.0/2293.64.108.1 to 93.64.111.25493.64.111.2551,022
2993.64.112.0/2293.64.112.1 to 93.64.115.25493.64.115.2551,022
3093.64.116.0/2293.64.116.1 to 93.64.119.25493.64.119.2551,022
3193.64.120.0/2293.64.120.1 to 93.64.123.25493.64.123.2551,022
3293.64.124.0/2293.64.124.1 to 93.64.127.25493.64.127.2551,022
3393.64.128.0/2293.64.128.1 to 93.64.131.25493.64.131.2551,022
3493.64.132.0/2293.64.132.1 to 93.64.135.25493.64.135.2551,022
3593.64.136.0/2293.64.136.1 to 93.64.139.25493.64.139.2551,022
3693.64.140.0/2293.64.140.1 to 93.64.143.25493.64.143.2551,022
3793.64.144.0/2293.64.144.1 to 93.64.147.25493.64.147.2551,022
3893.64.148.0/2293.64.148.1 to 93.64.151.25493.64.151.2551,022
3993.64.152.0/2293.64.152.1 to 93.64.155.25493.64.155.2551,022
4093.64.156.0/2293.64.156.1 to 93.64.159.25493.64.159.2551,022
4193.64.160.0/2293.64.160.1 to 93.64.163.25493.64.163.2551,022
4293.64.164.0/2293.64.164.1 to 93.64.167.25493.64.167.2551,022
4393.64.168.0/2293.64.168.1 to 93.64.171.25493.64.171.2551,022
4493.64.172.0/2293.64.172.1 to 93.64.175.25493.64.175.2551,022
4593.64.176.0/2293.64.176.1 to 93.64.179.25493.64.179.2551,022
4693.64.180.0/2293.64.180.1 to 93.64.183.25493.64.183.2551,022
4793.64.184.0/2293.64.184.1 to 93.64.187.25493.64.187.2551,022
4893.64.188.0/2293.64.188.1 to 93.64.191.25493.64.191.2551,022
4993.64.192.0/2293.64.192.1 to 93.64.195.25493.64.195.2551,022
5093.64.196.0/2293.64.196.1 to 93.64.199.25493.64.199.2551,022
5193.64.200.0/2293.64.200.1 to 93.64.203.25493.64.203.2551,022
5293.64.204.0/2293.64.204.1 to 93.64.207.25493.64.207.2551,022
5393.64.208.0/2293.64.208.1 to 93.64.211.25493.64.211.2551,022
5493.64.212.0/2293.64.212.1 to 93.64.215.25493.64.215.2551,022
5593.64.216.0/2293.64.216.1 to 93.64.219.25493.64.219.2551,022
5693.64.220.0/2293.64.220.1 to 93.64.223.25493.64.223.2551,022
5793.64.224.0/2293.64.224.1 to 93.64.227.25493.64.227.2551,022
5893.64.228.0/2293.64.228.1 to 93.64.231.25493.64.231.2551,022
5993.64.232.0/2293.64.232.1 to 93.64.235.25493.64.235.2551,022
6093.64.236.0/2293.64.236.1 to 93.64.239.25493.64.239.2551,022
6193.64.240.0/2293.64.240.1 to 93.64.243.25493.64.243.2551,022
6293.64.244.0/2293.64.244.1 to 93.64.247.25493.64.247.2551,022
6393.64.248.0/2293.64.248.1 to 93.64.251.25493.64.251.2551,022
6493.64.252.0/2293.64.252.1 to 93.64.255.25493.64.255.2551,022
6593.65.0.0/2293.65.0.1 to 93.65.3.25493.65.3.2551,022
6693.65.4.0/2293.65.4.1 to 93.65.7.25493.65.7.2551,022
6793.65.8.0/2293.65.8.1 to 93.65.11.25493.65.11.2551,022
6893.65.12.0/2293.65.12.1 to 93.65.15.25493.65.15.2551,022
6993.65.16.0/2293.65.16.1 to 93.65.19.25493.65.19.2551,022
7093.65.20.0/2293.65.20.1 to 93.65.23.25493.65.23.2551,022
7193.65.24.0/2293.65.24.1 to 93.65.27.25493.65.27.2551,022
7293.65.28.0/2293.65.28.1 to 93.65.31.25493.65.31.2551,022
7393.65.32.0/2293.65.32.1 to 93.65.35.25493.65.35.2551,022
7493.65.36.0/2293.65.36.1 to 93.65.39.25493.65.39.2551,022
7593.65.40.0/2293.65.40.1 to 93.65.43.25493.65.43.2551,022
7693.65.44.0/2293.65.44.1 to 93.65.47.25493.65.47.2551,022
7793.65.48.0/2293.65.48.1 to 93.65.51.25493.65.51.2551,022
7893.65.52.0/2293.65.52.1 to 93.65.55.25493.65.55.2551,022
7993.65.56.0/2293.65.56.1 to 93.65.59.25493.65.59.2551,022
8093.65.60.0/2293.65.60.1 to 93.65.63.25493.65.63.2551,022
8193.65.64.0/2293.65.64.1 to 93.65.67.25493.65.67.2551,022
8293.65.68.0/2293.65.68.1 to 93.65.71.25493.65.71.2551,022
8393.65.72.0/2293.65.72.1 to 93.65.75.25493.65.75.2551,022
8493.65.76.0/2293.65.76.1 to 93.65.79.25493.65.79.2551,022
8593.65.80.0/2293.65.80.1 to 93.65.83.25493.65.83.2551,022
8693.65.84.0/2293.65.84.1 to 93.65.87.25493.65.87.2551,022
8793.65.88.0/2293.65.88.1 to 93.65.91.25493.65.91.2551,022
8893.65.92.0/2293.65.92.1 to 93.65.95.25493.65.95.2551,022
8993.65.96.0/2293.65.96.1 to 93.65.99.25493.65.99.2551,022
9093.65.100.0/2293.65.100.1 to 93.65.103.25493.65.103.2551,022
9193.65.104.0/2293.65.104.1 to 93.65.107.25493.65.107.2551,022
9293.65.108.0/2293.65.108.1 to 93.65.111.25493.65.111.2551,022
9393.65.112.0/2293.65.112.1 to 93.65.115.25493.65.115.2551,022
9493.65.116.0/2293.65.116.1 to 93.65.119.25493.65.119.2551,022
9593.65.120.0/2293.65.120.1 to 93.65.123.25493.65.123.2551,022
9693.65.124.0/2293.65.124.1 to 93.65.127.25493.65.127.2551,022
9793.65.128.0/2293.65.128.1 to 93.65.131.25493.65.131.2551,022
9893.65.132.0/2293.65.132.1 to 93.65.135.25493.65.135.2551,022
9993.65.136.0/2293.65.136.1 to 93.65.139.25493.65.139.2551,022
10093.65.140.0/2293.65.140.1 to 93.65.143.25493.65.143.2551,022
10193.65.144.0/2293.65.144.1 to 93.65.147.25493.65.147.2551,022
10293.65.148.0/2293.65.148.1 to 93.65.151.25493.65.151.2551,022
10393.65.152.0/2293.65.152.1 to 93.65.155.25493.65.155.2551,022
10493.65.156.0/2293.65.156.1 to 93.65.159.25493.65.159.2551,022
10593.65.160.0/2293.65.160.1 to 93.65.163.25493.65.163.2551,022
10693.65.164.0/2293.65.164.1 to 93.65.167.25493.65.167.2551,022
10793.65.168.0/2293.65.168.1 to 93.65.171.25493.65.171.2551,022
10893.65.172.0/2293.65.172.1 to 93.65.175.25493.65.175.2551,022
10993.65.176.0/2293.65.176.1 to 93.65.179.25493.65.179.2551,022
11093.65.180.0/2293.65.180.1 to 93.65.183.25493.65.183.2551,022
11193.65.184.0/2293.65.184.1 to 93.65.187.25493.65.187.2551,022
11293.65.188.0/2293.65.188.1 to 93.65.191.25493.65.191.2551,022
11393.65.192.0/2293.65.192.1 to 93.65.195.25493.65.195.2551,022
11493.65.196.0/2293.65.196.1 to 93.65.199.25493.65.199.2551,022
11593.65.200.0/2293.65.200.1 to 93.65.203.25493.65.203.2551,022
11693.65.204.0/2293.65.204.1 to 93.65.207.25493.65.207.2551,022
11793.65.208.0/2293.65.208.1 to 93.65.211.25493.65.211.2551,022
11893.65.212.0/2293.65.212.1 to 93.65.215.25493.65.215.2551,022
11993.65.216.0/2293.65.216.1 to 93.65.219.25493.65.219.2551,022
12093.65.220.0/2293.65.220.1 to 93.65.223.25493.65.223.2551,022
12193.65.224.0/2293.65.224.1 to 93.65.227.25493.65.227.2551,022
12293.65.228.0/2293.65.228.1 to 93.65.231.25493.65.231.2551,022
12393.65.232.0/2293.65.232.1 to 93.65.235.25493.65.235.2551,022
12493.65.236.0/2293.65.236.1 to 93.65.239.25493.65.239.2551,022
12593.65.240.0/2293.65.240.1 to 93.65.243.25493.65.243.2551,022
12693.65.244.0/2293.65.244.1 to 93.65.247.25493.65.247.2551,022
12793.65.248.0/2293.65.248.1 to 93.65.251.25493.65.251.2551,022
12893.65.252.0/2293.65.252.1 to 93.65.255.25493.65.255.2551,022
12993.66.0.0/2293.66.0.1 to 93.66.3.25493.66.3.2551,022
13093.66.4.0/2293.66.4.1 to 93.66.7.25493.66.7.2551,022
13193.66.8.0/2293.66.8.1 to 93.66.11.25493.66.11.2551,022
13293.66.12.0/2293.66.12.1 to 93.66.15.25493.66.15.2551,022
13393.66.16.0/2293.66.16.1 to 93.66.19.25493.66.19.2551,022
13493.66.20.0/2293.66.20.1 to 93.66.23.25493.66.23.2551,022
13593.66.24.0/2293.66.24.1 to 93.66.27.25493.66.27.2551,022
13693.66.28.0/2293.66.28.1 to 93.66.31.25493.66.31.2551,022
13793.66.32.0/2293.66.32.1 to 93.66.35.25493.66.35.2551,022
13893.66.36.0/2293.66.36.1 to 93.66.39.25493.66.39.2551,022
13993.66.40.0/2293.66.40.1 to 93.66.43.25493.66.43.2551,022
14093.66.44.0/2293.66.44.1 to 93.66.47.25493.66.47.2551,022
14193.66.48.0/2293.66.48.1 to 93.66.51.25493.66.51.2551,022
14293.66.52.0/2293.66.52.1 to 93.66.55.25493.66.55.2551,022
14393.66.56.0/2293.66.56.1 to 93.66.59.25493.66.59.2551,022
14493.66.60.0/2293.66.60.1 to 93.66.63.25493.66.63.2551,022
14593.66.64.0/2293.66.64.1 to 93.66.67.25493.66.67.2551,022
14693.66.68.0/2293.66.68.1 to 93.66.71.25493.66.71.2551,022
14793.66.72.0/2293.66.72.1 to 93.66.75.25493.66.75.2551,022
14893.66.76.0/2293.66.76.1 to 93.66.79.25493.66.79.2551,022
14993.66.80.0/2293.66.80.1 to 93.66.83.25493.66.83.2551,022
15093.66.84.0/2293.66.84.1 to 93.66.87.25493.66.87.2551,022
15193.66.88.0/2293.66.88.1 to 93.66.91.25493.66.91.2551,022
15293.66.92.0/2293.66.92.1 to 93.66.95.25493.66.95.2551,022
15393.66.96.0/2293.66.96.1 to 93.66.99.25493.66.99.2551,022
15493.66.100.0/2293.66.100.1 to 93.66.103.25493.66.103.2551,022
15593.66.104.0/2293.66.104.1 to 93.66.107.25493.66.107.2551,022
15693.66.108.0/2293.66.108.1 to 93.66.111.25493.66.111.2551,022
15793.66.112.0/2293.66.112.1 to 93.66.115.25493.66.115.2551,022
15893.66.116.0/2293.66.116.1 to 93.66.119.25493.66.119.2551,022
15993.66.120.0/2293.66.120.1 to 93.66.123.25493.66.123.2551,022
16093.66.124.0/2293.66.124.1 to 93.66.127.25493.66.127.2551,022
16193.66.128.0/2293.66.128.1 to 93.66.131.25493.66.131.2551,022
16293.66.132.0/2293.66.132.1 to 93.66.135.25493.66.135.2551,022
16393.66.136.0/2293.66.136.1 to 93.66.139.25493.66.139.2551,022
16493.66.140.0/2293.66.140.1 to 93.66.143.25493.66.143.2551,022
16593.66.144.0/2293.66.144.1 to 93.66.147.25493.66.147.2551,022
16693.66.148.0/2293.66.148.1 to 93.66.151.25493.66.151.2551,022
16793.66.152.0/2293.66.152.1 to 93.66.155.25493.66.155.2551,022
16893.66.156.0/2293.66.156.1 to 93.66.159.25493.66.159.2551,022
16993.66.160.0/2293.66.160.1 to 93.66.163.25493.66.163.2551,022
17093.66.164.0/2293.66.164.1 to 93.66.167.25493.66.167.2551,022
17193.66.168.0/2293.66.168.1 to 93.66.171.25493.66.171.2551,022
17293.66.172.0/2293.66.172.1 to 93.66.175.25493.66.175.2551,022
17393.66.176.0/2293.66.176.1 to 93.66.179.25493.66.179.2551,022
17493.66.180.0/2293.66.180.1 to 93.66.183.25493.66.183.2551,022
17593.66.184.0/2293.66.184.1 to 93.66.187.25493.66.187.2551,022
17693.66.188.0/2293.66.188.1 to 93.66.191.25493.66.191.2551,022
17793.66.192.0/2293.66.192.1 to 93.66.195.25493.66.195.2551,022
17893.66.196.0/2293.66.196.1 to 93.66.199.25493.66.199.2551,022
17993.66.200.0/2293.66.200.1 to 93.66.203.25493.66.203.2551,022
18093.66.204.0/2293.66.204.1 to 93.66.207.25493.66.207.2551,022
18193.66.208.0/2293.66.208.1 to 93.66.211.25493.66.211.2551,022
18293.66.212.0/2293.66.212.1 to 93.66.215.25493.66.215.2551,022
18393.66.216.0/2293.66.216.1 to 93.66.219.25493.66.219.2551,022
18493.66.220.0/2293.66.220.1 to 93.66.223.25493.66.223.2551,022
18593.66.224.0/2293.66.224.1 to 93.66.227.25493.66.227.2551,022
18693.66.228.0/2293.66.228.1 to 93.66.231.25493.66.231.2551,022
18793.66.232.0/2293.66.232.1 to 93.66.235.25493.66.235.2551,022
18893.66.236.0/2293.66.236.1 to 93.66.239.25493.66.239.2551,022
18993.66.240.0/2293.66.240.1 to 93.66.243.25493.66.243.2551,022
19093.66.244.0/2293.66.244.1 to 93.66.247.25493.66.247.2551,022
19193.66.248.0/2293.66.248.1 to 93.66.251.25493.66.251.2551,022
19293.66.252.0/2293.66.252.1 to 93.66.255.25493.66.255.2551,022
19393.67.0.0/2293.67.0.1 to 93.67.3.25493.67.3.2551,022
19493.67.4.0/2293.67.4.1 to 93.67.7.25493.67.7.2551,022
19593.67.8.0/2293.67.8.1 to 93.67.11.25493.67.11.2551,022
19693.67.12.0/2293.67.12.1 to 93.67.15.25493.67.15.2551,022
19793.67.16.0/2293.67.16.1 to 93.67.19.25493.67.19.2551,022
19893.67.20.0/2293.67.20.1 to 93.67.23.25493.67.23.2551,022
19993.67.24.0/2293.67.24.1 to 93.67.27.25493.67.27.2551,022
20093.67.28.0/2293.67.28.1 to 93.67.31.25493.67.31.2551,022
20193.67.32.0/2293.67.32.1 to 93.67.35.25493.67.35.2551,022
20293.67.36.0/2293.67.36.1 to 93.67.39.25493.67.39.2551,022
20393.67.40.0/2293.67.40.1 to 93.67.43.25493.67.43.2551,022
20493.67.44.0/2293.67.44.1 to 93.67.47.25493.67.47.2551,022
20593.67.48.0/2293.67.48.1 to 93.67.51.25493.67.51.2551,022
20693.67.52.0/2293.67.52.1 to 93.67.55.25493.67.55.2551,022
20793.67.56.0/2293.67.56.1 to 93.67.59.25493.67.59.2551,022
20893.67.60.0/2293.67.60.1 to 93.67.63.25493.67.63.2551,022
20993.67.64.0/2293.67.64.1 to 93.67.67.25493.67.67.2551,022
21093.67.68.0/2293.67.68.1 to 93.67.71.25493.67.71.2551,022
21193.67.72.0/2293.67.72.1 to 93.67.75.25493.67.75.2551,022
21293.67.76.0/2293.67.76.1 to 93.67.79.25493.67.79.2551,022
21393.67.80.0/2293.67.80.1 to 93.67.83.25493.67.83.2551,022
21493.67.84.0/2293.67.84.1 to 93.67.87.25493.67.87.2551,022
21593.67.88.0/2293.67.88.1 to 93.67.91.25493.67.91.2551,022
21693.67.92.0/2293.67.92.1 to 93.67.95.25493.67.95.2551,022
21793.67.96.0/2293.67.96.1 to 93.67.99.25493.67.99.2551,022
21893.67.100.0/2293.67.100.1 to 93.67.103.25493.67.103.2551,022
21993.67.104.0/2293.67.104.1 to 93.67.107.25493.67.107.2551,022
22093.67.108.0/2293.67.108.1 to 93.67.111.25493.67.111.2551,022
22193.67.112.0/2293.67.112.1 to 93.67.115.25493.67.115.2551,022
22293.67.116.0/2293.67.116.1 to 93.67.119.25493.67.119.2551,022
22393.67.120.0/2293.67.120.1 to 93.67.123.25493.67.123.2551,022
22493.67.124.0/2293.67.124.1 to 93.67.127.25493.67.127.2551,022
22593.67.128.0/2293.67.128.1 to 93.67.131.25493.67.131.2551,022
22693.67.132.0/2293.67.132.1 to 93.67.135.25493.67.135.2551,022
22793.67.136.0/2293.67.136.1 to 93.67.139.25493.67.139.2551,022
22893.67.140.0/2293.67.140.1 to 93.67.143.25493.67.143.2551,022
22993.67.144.0/2293.67.144.1 to 93.67.147.25493.67.147.2551,022
23093.67.148.0/2293.67.148.1 to 93.67.151.25493.67.151.2551,022
23193.67.152.0/2293.67.152.1 to 93.67.155.25493.67.155.2551,022
23293.67.156.0/2293.67.156.1 to 93.67.159.25493.67.159.2551,022
23393.67.160.0/2293.67.160.1 to 93.67.163.25493.67.163.2551,022
23493.67.164.0/2293.67.164.1 to 93.67.167.25493.67.167.2551,022
23593.67.168.0/2293.67.168.1 to 93.67.171.25493.67.171.2551,022
23693.67.172.0/2293.67.172.1 to 93.67.175.25493.67.175.2551,022
23793.67.176.0/2293.67.176.1 to 93.67.179.25493.67.179.2551,022
23893.67.180.0/2293.67.180.1 to 93.67.183.25493.67.183.2551,022
23993.67.184.0/2293.67.184.1 to 93.67.187.25493.67.187.2551,022
24093.67.188.0/2293.67.188.1 to 93.67.191.25493.67.191.2551,022
24193.67.192.0/2293.67.192.1 to 93.67.195.25493.67.195.2551,022
24293.67.196.0/2293.67.196.1 to 93.67.199.25493.67.199.2551,022
24393.67.200.0/2293.67.200.1 to 93.67.203.25493.67.203.2551,022
24493.67.204.0/2293.67.204.1 to 93.67.207.25493.67.207.2551,022
24593.67.208.0/2293.67.208.1 to 93.67.211.25493.67.211.2551,022
24693.67.212.0/2293.67.212.1 to 93.67.215.25493.67.215.2551,022
24793.67.216.0/2293.67.216.1 to 93.67.219.25493.67.219.2551,022
24893.67.220.0/2293.67.220.1 to 93.67.223.25493.67.223.2551,022
24993.67.224.0/2293.67.224.1 to 93.67.227.25493.67.227.2551,022
25093.67.228.0/2293.67.228.1 to 93.67.231.25493.67.231.2551,022
25193.67.232.0/2293.67.232.1 to 93.67.235.25493.67.235.2551,022
25293.67.236.0/2293.67.236.1 to 93.67.239.25493.67.239.2551,022
25393.67.240.0/2293.67.240.1 to 93.67.243.25493.67.243.2551,022
25493.67.244.0/2293.67.244.1 to 93.67.247.25493.67.247.2551,022
25593.67.248.0/2293.67.248.1 to 93.67.251.25493.67.251.2551,022
25693.67.252.0/2293.67.252.1 to 93.67.255.25493.67.255.2551,022

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.