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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.

Network93.0.0.0/15
Usable hosts131,070
Subnet mask255.254.0.0
Addresses131,072
Network address
93.0.0.0
Broadcast address
93.1.255.255
First usable
93.0.0.1
Last usable
93.1.255.254
Usable hosts
131,070 (131,072 less the network and broadcast addresses)
Subnet mask
255.254.0.0
Wildcard mask
0.1.255.255 (Cisco ACLs, OSPF)
Prefix length
/15
Type
Public public
Old class
A (default /8)
As numbers
Hex 5D000000 · Integer 1560281088 to 1560412159
Reverse DNS zones
0.93.in-addr.arpa
1.93.in-addr.arpa
/15 is not on a 8-bit boundary, so it takes 2 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011101.00000000.00000000.0000000093.0.0.0
Subnet mask11111111.11111110.00000000.00000000255.254.0.0
Network01011101.00000000.00000000.0000000093.0.0.0
Broadcast01011101.00000001.11111111.1111111193.1.255.255
Split into smaller subnets/23
/16 (2)/17 (4)/18 (8)/19 (16)/20 (32)/21 (64)/22 (128)/23 (256)/24 (512)/25 (1,024)/26 (2,048)/27 (4,096)

93.0.0.0/15 makes 256 subnets of /23.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
193.0.0.0/2393.0.0.1 to 93.0.1.25493.0.1.255510
293.0.2.0/2393.0.2.1 to 93.0.3.25493.0.3.255510
393.0.4.0/2393.0.4.1 to 93.0.5.25493.0.5.255510
493.0.6.0/2393.0.6.1 to 93.0.7.25493.0.7.255510
593.0.8.0/2393.0.8.1 to 93.0.9.25493.0.9.255510
693.0.10.0/2393.0.10.1 to 93.0.11.25493.0.11.255510
793.0.12.0/2393.0.12.1 to 93.0.13.25493.0.13.255510
893.0.14.0/2393.0.14.1 to 93.0.15.25493.0.15.255510
993.0.16.0/2393.0.16.1 to 93.0.17.25493.0.17.255510
1093.0.18.0/2393.0.18.1 to 93.0.19.25493.0.19.255510
1193.0.20.0/2393.0.20.1 to 93.0.21.25493.0.21.255510
1293.0.22.0/2393.0.22.1 to 93.0.23.25493.0.23.255510
1393.0.24.0/2393.0.24.1 to 93.0.25.25493.0.25.255510
1493.0.26.0/2393.0.26.1 to 93.0.27.25493.0.27.255510
1593.0.28.0/2393.0.28.1 to 93.0.29.25493.0.29.255510
1693.0.30.0/2393.0.30.1 to 93.0.31.25493.0.31.255510
1793.0.32.0/2393.0.32.1 to 93.0.33.25493.0.33.255510
1893.0.34.0/2393.0.34.1 to 93.0.35.25493.0.35.255510
1993.0.36.0/2393.0.36.1 to 93.0.37.25493.0.37.255510
2093.0.38.0/2393.0.38.1 to 93.0.39.25493.0.39.255510
2193.0.40.0/2393.0.40.1 to 93.0.41.25493.0.41.255510
2293.0.42.0/2393.0.42.1 to 93.0.43.25493.0.43.255510
2393.0.44.0/2393.0.44.1 to 93.0.45.25493.0.45.255510
2493.0.46.0/2393.0.46.1 to 93.0.47.25493.0.47.255510
2593.0.48.0/2393.0.48.1 to 93.0.49.25493.0.49.255510
2693.0.50.0/2393.0.50.1 to 93.0.51.25493.0.51.255510
2793.0.52.0/2393.0.52.1 to 93.0.53.25493.0.53.255510
2893.0.54.0/2393.0.54.1 to 93.0.55.25493.0.55.255510
2993.0.56.0/2393.0.56.1 to 93.0.57.25493.0.57.255510
3093.0.58.0/2393.0.58.1 to 93.0.59.25493.0.59.255510
3193.0.60.0/2393.0.60.1 to 93.0.61.25493.0.61.255510
3293.0.62.0/2393.0.62.1 to 93.0.63.25493.0.63.255510
3393.0.64.0/2393.0.64.1 to 93.0.65.25493.0.65.255510
3493.0.66.0/2393.0.66.1 to 93.0.67.25493.0.67.255510
3593.0.68.0/2393.0.68.1 to 93.0.69.25493.0.69.255510
3693.0.70.0/2393.0.70.1 to 93.0.71.25493.0.71.255510
3793.0.72.0/2393.0.72.1 to 93.0.73.25493.0.73.255510
3893.0.74.0/2393.0.74.1 to 93.0.75.25493.0.75.255510
3993.0.76.0/2393.0.76.1 to 93.0.77.25493.0.77.255510
4093.0.78.0/2393.0.78.1 to 93.0.79.25493.0.79.255510
4193.0.80.0/2393.0.80.1 to 93.0.81.25493.0.81.255510
4293.0.82.0/2393.0.82.1 to 93.0.83.25493.0.83.255510
4393.0.84.0/2393.0.84.1 to 93.0.85.25493.0.85.255510
4493.0.86.0/2393.0.86.1 to 93.0.87.25493.0.87.255510
4593.0.88.0/2393.0.88.1 to 93.0.89.25493.0.89.255510
4693.0.90.0/2393.0.90.1 to 93.0.91.25493.0.91.255510
4793.0.92.0/2393.0.92.1 to 93.0.93.25493.0.93.255510
4893.0.94.0/2393.0.94.1 to 93.0.95.25493.0.95.255510
4993.0.96.0/2393.0.96.1 to 93.0.97.25493.0.97.255510
5093.0.98.0/2393.0.98.1 to 93.0.99.25493.0.99.255510
5193.0.100.0/2393.0.100.1 to 93.0.101.25493.0.101.255510
5293.0.102.0/2393.0.102.1 to 93.0.103.25493.0.103.255510
5393.0.104.0/2393.0.104.1 to 93.0.105.25493.0.105.255510
5493.0.106.0/2393.0.106.1 to 93.0.107.25493.0.107.255510
5593.0.108.0/2393.0.108.1 to 93.0.109.25493.0.109.255510
5693.0.110.0/2393.0.110.1 to 93.0.111.25493.0.111.255510
5793.0.112.0/2393.0.112.1 to 93.0.113.25493.0.113.255510
5893.0.114.0/2393.0.114.1 to 93.0.115.25493.0.115.255510
5993.0.116.0/2393.0.116.1 to 93.0.117.25493.0.117.255510
6093.0.118.0/2393.0.118.1 to 93.0.119.25493.0.119.255510
6193.0.120.0/2393.0.120.1 to 93.0.121.25493.0.121.255510
6293.0.122.0/2393.0.122.1 to 93.0.123.25493.0.123.255510
6393.0.124.0/2393.0.124.1 to 93.0.125.25493.0.125.255510
6493.0.126.0/2393.0.126.1 to 93.0.127.25493.0.127.255510
6593.0.128.0/2393.0.128.1 to 93.0.129.25493.0.129.255510
6693.0.130.0/2393.0.130.1 to 93.0.131.25493.0.131.255510
6793.0.132.0/2393.0.132.1 to 93.0.133.25493.0.133.255510
6893.0.134.0/2393.0.134.1 to 93.0.135.25493.0.135.255510
6993.0.136.0/2393.0.136.1 to 93.0.137.25493.0.137.255510
7093.0.138.0/2393.0.138.1 to 93.0.139.25493.0.139.255510
7193.0.140.0/2393.0.140.1 to 93.0.141.25493.0.141.255510
7293.0.142.0/2393.0.142.1 to 93.0.143.25493.0.143.255510
7393.0.144.0/2393.0.144.1 to 93.0.145.25493.0.145.255510
7493.0.146.0/2393.0.146.1 to 93.0.147.25493.0.147.255510
7593.0.148.0/2393.0.148.1 to 93.0.149.25493.0.149.255510
7693.0.150.0/2393.0.150.1 to 93.0.151.25493.0.151.255510
7793.0.152.0/2393.0.152.1 to 93.0.153.25493.0.153.255510
7893.0.154.0/2393.0.154.1 to 93.0.155.25493.0.155.255510
7993.0.156.0/2393.0.156.1 to 93.0.157.25493.0.157.255510
8093.0.158.0/2393.0.158.1 to 93.0.159.25493.0.159.255510
8193.0.160.0/2393.0.160.1 to 93.0.161.25493.0.161.255510
8293.0.162.0/2393.0.162.1 to 93.0.163.25493.0.163.255510
8393.0.164.0/2393.0.164.1 to 93.0.165.25493.0.165.255510
8493.0.166.0/2393.0.166.1 to 93.0.167.25493.0.167.255510
8593.0.168.0/2393.0.168.1 to 93.0.169.25493.0.169.255510
8693.0.170.0/2393.0.170.1 to 93.0.171.25493.0.171.255510
8793.0.172.0/2393.0.172.1 to 93.0.173.25493.0.173.255510
8893.0.174.0/2393.0.174.1 to 93.0.175.25493.0.175.255510
8993.0.176.0/2393.0.176.1 to 93.0.177.25493.0.177.255510
9093.0.178.0/2393.0.178.1 to 93.0.179.25493.0.179.255510
9193.0.180.0/2393.0.180.1 to 93.0.181.25493.0.181.255510
9293.0.182.0/2393.0.182.1 to 93.0.183.25493.0.183.255510
9393.0.184.0/2393.0.184.1 to 93.0.185.25493.0.185.255510
9493.0.186.0/2393.0.186.1 to 93.0.187.25493.0.187.255510
9593.0.188.0/2393.0.188.1 to 93.0.189.25493.0.189.255510
9693.0.190.0/2393.0.190.1 to 93.0.191.25493.0.191.255510
9793.0.192.0/2393.0.192.1 to 93.0.193.25493.0.193.255510
9893.0.194.0/2393.0.194.1 to 93.0.195.25493.0.195.255510
9993.0.196.0/2393.0.196.1 to 93.0.197.25493.0.197.255510
10093.0.198.0/2393.0.198.1 to 93.0.199.25493.0.199.255510
10193.0.200.0/2393.0.200.1 to 93.0.201.25493.0.201.255510
10293.0.202.0/2393.0.202.1 to 93.0.203.25493.0.203.255510
10393.0.204.0/2393.0.204.1 to 93.0.205.25493.0.205.255510
10493.0.206.0/2393.0.206.1 to 93.0.207.25493.0.207.255510
10593.0.208.0/2393.0.208.1 to 93.0.209.25493.0.209.255510
10693.0.210.0/2393.0.210.1 to 93.0.211.25493.0.211.255510
10793.0.212.0/2393.0.212.1 to 93.0.213.25493.0.213.255510
10893.0.214.0/2393.0.214.1 to 93.0.215.25493.0.215.255510
10993.0.216.0/2393.0.216.1 to 93.0.217.25493.0.217.255510
11093.0.218.0/2393.0.218.1 to 93.0.219.25493.0.219.255510
11193.0.220.0/2393.0.220.1 to 93.0.221.25493.0.221.255510
11293.0.222.0/2393.0.222.1 to 93.0.223.25493.0.223.255510
11393.0.224.0/2393.0.224.1 to 93.0.225.25493.0.225.255510
11493.0.226.0/2393.0.226.1 to 93.0.227.25493.0.227.255510
11593.0.228.0/2393.0.228.1 to 93.0.229.25493.0.229.255510
11693.0.230.0/2393.0.230.1 to 93.0.231.25493.0.231.255510
11793.0.232.0/2393.0.232.1 to 93.0.233.25493.0.233.255510
11893.0.234.0/2393.0.234.1 to 93.0.235.25493.0.235.255510
11993.0.236.0/2393.0.236.1 to 93.0.237.25493.0.237.255510
12093.0.238.0/2393.0.238.1 to 93.0.239.25493.0.239.255510
12193.0.240.0/2393.0.240.1 to 93.0.241.25493.0.241.255510
12293.0.242.0/2393.0.242.1 to 93.0.243.25493.0.243.255510
12393.0.244.0/2393.0.244.1 to 93.0.245.25493.0.245.255510
12493.0.246.0/2393.0.246.1 to 93.0.247.25493.0.247.255510
12593.0.248.0/2393.0.248.1 to 93.0.249.25493.0.249.255510
12693.0.250.0/2393.0.250.1 to 93.0.251.25493.0.251.255510
12793.0.252.0/2393.0.252.1 to 93.0.253.25493.0.253.255510
12893.0.254.0/2393.0.254.1 to 93.0.255.25493.0.255.255510
12993.1.0.0/2393.1.0.1 to 93.1.1.25493.1.1.255510
13093.1.2.0/2393.1.2.1 to 93.1.3.25493.1.3.255510
13193.1.4.0/2393.1.4.1 to 93.1.5.25493.1.5.255510
13293.1.6.0/2393.1.6.1 to 93.1.7.25493.1.7.255510
13393.1.8.0/2393.1.8.1 to 93.1.9.25493.1.9.255510
13493.1.10.0/2393.1.10.1 to 93.1.11.25493.1.11.255510
13593.1.12.0/2393.1.12.1 to 93.1.13.25493.1.13.255510
13693.1.14.0/2393.1.14.1 to 93.1.15.25493.1.15.255510
13793.1.16.0/2393.1.16.1 to 93.1.17.25493.1.17.255510
13893.1.18.0/2393.1.18.1 to 93.1.19.25493.1.19.255510
13993.1.20.0/2393.1.20.1 to 93.1.21.25493.1.21.255510
14093.1.22.0/2393.1.22.1 to 93.1.23.25493.1.23.255510
14193.1.24.0/2393.1.24.1 to 93.1.25.25493.1.25.255510
14293.1.26.0/2393.1.26.1 to 93.1.27.25493.1.27.255510
14393.1.28.0/2393.1.28.1 to 93.1.29.25493.1.29.255510
14493.1.30.0/2393.1.30.1 to 93.1.31.25493.1.31.255510
14593.1.32.0/2393.1.32.1 to 93.1.33.25493.1.33.255510
14693.1.34.0/2393.1.34.1 to 93.1.35.25493.1.35.255510
14793.1.36.0/2393.1.36.1 to 93.1.37.25493.1.37.255510
14893.1.38.0/2393.1.38.1 to 93.1.39.25493.1.39.255510
14993.1.40.0/2393.1.40.1 to 93.1.41.25493.1.41.255510
15093.1.42.0/2393.1.42.1 to 93.1.43.25493.1.43.255510
15193.1.44.0/2393.1.44.1 to 93.1.45.25493.1.45.255510
15293.1.46.0/2393.1.46.1 to 93.1.47.25493.1.47.255510
15393.1.48.0/2393.1.48.1 to 93.1.49.25493.1.49.255510
15493.1.50.0/2393.1.50.1 to 93.1.51.25493.1.51.255510
15593.1.52.0/2393.1.52.1 to 93.1.53.25493.1.53.255510
15693.1.54.0/2393.1.54.1 to 93.1.55.25493.1.55.255510
15793.1.56.0/2393.1.56.1 to 93.1.57.25493.1.57.255510
15893.1.58.0/2393.1.58.1 to 93.1.59.25493.1.59.255510
15993.1.60.0/2393.1.60.1 to 93.1.61.25493.1.61.255510
16093.1.62.0/2393.1.62.1 to 93.1.63.25493.1.63.255510
16193.1.64.0/2393.1.64.1 to 93.1.65.25493.1.65.255510
16293.1.66.0/2393.1.66.1 to 93.1.67.25493.1.67.255510
16393.1.68.0/2393.1.68.1 to 93.1.69.25493.1.69.255510
16493.1.70.0/2393.1.70.1 to 93.1.71.25493.1.71.255510
16593.1.72.0/2393.1.72.1 to 93.1.73.25493.1.73.255510
16693.1.74.0/2393.1.74.1 to 93.1.75.25493.1.75.255510
16793.1.76.0/2393.1.76.1 to 93.1.77.25493.1.77.255510
16893.1.78.0/2393.1.78.1 to 93.1.79.25493.1.79.255510
16993.1.80.0/2393.1.80.1 to 93.1.81.25493.1.81.255510
17093.1.82.0/2393.1.82.1 to 93.1.83.25493.1.83.255510
17193.1.84.0/2393.1.84.1 to 93.1.85.25493.1.85.255510
17293.1.86.0/2393.1.86.1 to 93.1.87.25493.1.87.255510
17393.1.88.0/2393.1.88.1 to 93.1.89.25493.1.89.255510
17493.1.90.0/2393.1.90.1 to 93.1.91.25493.1.91.255510
17593.1.92.0/2393.1.92.1 to 93.1.93.25493.1.93.255510
17693.1.94.0/2393.1.94.1 to 93.1.95.25493.1.95.255510
17793.1.96.0/2393.1.96.1 to 93.1.97.25493.1.97.255510
17893.1.98.0/2393.1.98.1 to 93.1.99.25493.1.99.255510
17993.1.100.0/2393.1.100.1 to 93.1.101.25493.1.101.255510
18093.1.102.0/2393.1.102.1 to 93.1.103.25493.1.103.255510
18193.1.104.0/2393.1.104.1 to 93.1.105.25493.1.105.255510
18293.1.106.0/2393.1.106.1 to 93.1.107.25493.1.107.255510
18393.1.108.0/2393.1.108.1 to 93.1.109.25493.1.109.255510
18493.1.110.0/2393.1.110.1 to 93.1.111.25493.1.111.255510
18593.1.112.0/2393.1.112.1 to 93.1.113.25493.1.113.255510
18693.1.114.0/2393.1.114.1 to 93.1.115.25493.1.115.255510
18793.1.116.0/2393.1.116.1 to 93.1.117.25493.1.117.255510
18893.1.118.0/2393.1.118.1 to 93.1.119.25493.1.119.255510
18993.1.120.0/2393.1.120.1 to 93.1.121.25493.1.121.255510
19093.1.122.0/2393.1.122.1 to 93.1.123.25493.1.123.255510
19193.1.124.0/2393.1.124.1 to 93.1.125.25493.1.125.255510
19293.1.126.0/2393.1.126.1 to 93.1.127.25493.1.127.255510
19393.1.128.0/2393.1.128.1 to 93.1.129.25493.1.129.255510
19493.1.130.0/2393.1.130.1 to 93.1.131.25493.1.131.255510
19593.1.132.0/2393.1.132.1 to 93.1.133.25493.1.133.255510
19693.1.134.0/2393.1.134.1 to 93.1.135.25493.1.135.255510
19793.1.136.0/2393.1.136.1 to 93.1.137.25493.1.137.255510
19893.1.138.0/2393.1.138.1 to 93.1.139.25493.1.139.255510
19993.1.140.0/2393.1.140.1 to 93.1.141.25493.1.141.255510
20093.1.142.0/2393.1.142.1 to 93.1.143.25493.1.143.255510
20193.1.144.0/2393.1.144.1 to 93.1.145.25493.1.145.255510
20293.1.146.0/2393.1.146.1 to 93.1.147.25493.1.147.255510
20393.1.148.0/2393.1.148.1 to 93.1.149.25493.1.149.255510
20493.1.150.0/2393.1.150.1 to 93.1.151.25493.1.151.255510
20593.1.152.0/2393.1.152.1 to 93.1.153.25493.1.153.255510
20693.1.154.0/2393.1.154.1 to 93.1.155.25493.1.155.255510
20793.1.156.0/2393.1.156.1 to 93.1.157.25493.1.157.255510
20893.1.158.0/2393.1.158.1 to 93.1.159.25493.1.159.255510
20993.1.160.0/2393.1.160.1 to 93.1.161.25493.1.161.255510
21093.1.162.0/2393.1.162.1 to 93.1.163.25493.1.163.255510
21193.1.164.0/2393.1.164.1 to 93.1.165.25493.1.165.255510
21293.1.166.0/2393.1.166.1 to 93.1.167.25493.1.167.255510
21393.1.168.0/2393.1.168.1 to 93.1.169.25493.1.169.255510
21493.1.170.0/2393.1.170.1 to 93.1.171.25493.1.171.255510
21593.1.172.0/2393.1.172.1 to 93.1.173.25493.1.173.255510
21693.1.174.0/2393.1.174.1 to 93.1.175.25493.1.175.255510
21793.1.176.0/2393.1.176.1 to 93.1.177.25493.1.177.255510
21893.1.178.0/2393.1.178.1 to 93.1.179.25493.1.179.255510
21993.1.180.0/2393.1.180.1 to 93.1.181.25493.1.181.255510
22093.1.182.0/2393.1.182.1 to 93.1.183.25493.1.183.255510
22193.1.184.0/2393.1.184.1 to 93.1.185.25493.1.185.255510
22293.1.186.0/2393.1.186.1 to 93.1.187.25493.1.187.255510
22393.1.188.0/2393.1.188.1 to 93.1.189.25493.1.189.255510
22493.1.190.0/2393.1.190.1 to 93.1.191.25493.1.191.255510
22593.1.192.0/2393.1.192.1 to 93.1.193.25493.1.193.255510
22693.1.194.0/2393.1.194.1 to 93.1.195.25493.1.195.255510
22793.1.196.0/2393.1.196.1 to 93.1.197.25493.1.197.255510
22893.1.198.0/2393.1.198.1 to 93.1.199.25493.1.199.255510
22993.1.200.0/2393.1.200.1 to 93.1.201.25493.1.201.255510
23093.1.202.0/2393.1.202.1 to 93.1.203.25493.1.203.255510
23193.1.204.0/2393.1.204.1 to 93.1.205.25493.1.205.255510
23293.1.206.0/2393.1.206.1 to 93.1.207.25493.1.207.255510
23393.1.208.0/2393.1.208.1 to 93.1.209.25493.1.209.255510
23493.1.210.0/2393.1.210.1 to 93.1.211.25493.1.211.255510
23593.1.212.0/2393.1.212.1 to 93.1.213.25493.1.213.255510
23693.1.214.0/2393.1.214.1 to 93.1.215.25493.1.215.255510
23793.1.216.0/2393.1.216.1 to 93.1.217.25493.1.217.255510
23893.1.218.0/2393.1.218.1 to 93.1.219.25493.1.219.255510
23993.1.220.0/2393.1.220.1 to 93.1.221.25493.1.221.255510
24093.1.222.0/2393.1.222.1 to 93.1.223.25493.1.223.255510
24193.1.224.0/2393.1.224.1 to 93.1.225.25493.1.225.255510
24293.1.226.0/2393.1.226.1 to 93.1.227.25493.1.227.255510
24393.1.228.0/2393.1.228.1 to 93.1.229.25493.1.229.255510
24493.1.230.0/2393.1.230.1 to 93.1.231.25493.1.231.255510
24593.1.232.0/2393.1.232.1 to 93.1.233.25493.1.233.255510
24693.1.234.0/2393.1.234.1 to 93.1.235.25493.1.235.255510
24793.1.236.0/2393.1.236.1 to 93.1.237.25493.1.237.255510
24893.1.238.0/2393.1.238.1 to 93.1.239.25493.1.239.255510
24993.1.240.0/2393.1.240.1 to 93.1.241.25493.1.241.255510
25093.1.242.0/2393.1.242.1 to 93.1.243.25493.1.243.255510
25193.1.244.0/2393.1.244.1 to 93.1.245.25493.1.245.255510
25293.1.246.0/2393.1.246.1 to 93.1.247.25493.1.247.255510
25393.1.248.0/2393.1.248.1 to 93.1.249.25493.1.249.255510
25493.1.250.0/2393.1.250.1 to 93.1.251.25493.1.251.255510
25593.1.252.0/2393.1.252.1 to 93.1.253.25493.1.253.255510
25693.1.254.0/2393.1.254.1 to 93.1.255.25493.1.255.255510

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.