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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.

Network52.0.0.0/6
Usable hosts67,108,862
Subnet mask252.0.0.0
Addresses67,108,864
Network address
52.0.0.0
Broadcast address
55.255.255.255
First usable
52.0.0.1
Last usable
55.255.255.254
Usable hosts
67,108,862 (67,108,864 less the network and broadcast addresses)
Subnet mask
252.0.0.0
Wildcard mask
3.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/6
Type
Public public
Old class
A (default /8)
As numbers
Hex 34000000 · Integer 872415232 to 939524095
Reverse DNS zones
52.in-addr.arpa
53.in-addr.arpa
54.in-addr.arpa
55.in-addr.arpa
/6 is not on a 8-bit boundary, so it takes 4 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110100.00000000.00000000.0000000052.0.0.0
Subnet mask11111100.00000000.00000000.00000000252.0.0.0
Network00110100.00000000.00000000.0000000052.0.0.0
Broadcast00110111.11111111.11111111.1111111155.255.255.255
Split into smaller subnets/15
/7 (2)/8 (4)/9 (8)/10 (16)/11 (32)/12 (64)/13 (128)/14 (256)/15 (512)/16 (1,024)/17 (2,048)/18 (4,096)

52.0.0.0/6 makes 512 subnets of /15; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
152.0.0.0/1552.0.0.1 to 52.1.255.25452.1.255.255131,070
252.2.0.0/1552.2.0.1 to 52.3.255.25452.3.255.255131,070
352.4.0.0/1552.4.0.1 to 52.5.255.25452.5.255.255131,070
452.6.0.0/1552.6.0.1 to 52.7.255.25452.7.255.255131,070
552.8.0.0/1552.8.0.1 to 52.9.255.25452.9.255.255131,070
652.10.0.0/1552.10.0.1 to 52.11.255.25452.11.255.255131,070
752.12.0.0/1552.12.0.1 to 52.13.255.25452.13.255.255131,070
852.14.0.0/1552.14.0.1 to 52.15.255.25452.15.255.255131,070
952.16.0.0/1552.16.0.1 to 52.17.255.25452.17.255.255131,070
1052.18.0.0/1552.18.0.1 to 52.19.255.25452.19.255.255131,070
1152.20.0.0/1552.20.0.1 to 52.21.255.25452.21.255.255131,070
1252.22.0.0/1552.22.0.1 to 52.23.255.25452.23.255.255131,070
1352.24.0.0/1552.24.0.1 to 52.25.255.25452.25.255.255131,070
1452.26.0.0/1552.26.0.1 to 52.27.255.25452.27.255.255131,070
1552.28.0.0/1552.28.0.1 to 52.29.255.25452.29.255.255131,070
1652.30.0.0/1552.30.0.1 to 52.31.255.25452.31.255.255131,070
1752.32.0.0/1552.32.0.1 to 52.33.255.25452.33.255.255131,070
1852.34.0.0/1552.34.0.1 to 52.35.255.25452.35.255.255131,070
1952.36.0.0/1552.36.0.1 to 52.37.255.25452.37.255.255131,070
2052.38.0.0/1552.38.0.1 to 52.39.255.25452.39.255.255131,070
2152.40.0.0/1552.40.0.1 to 52.41.255.25452.41.255.255131,070
2252.42.0.0/1552.42.0.1 to 52.43.255.25452.43.255.255131,070
2352.44.0.0/1552.44.0.1 to 52.45.255.25452.45.255.255131,070
2452.46.0.0/1552.46.0.1 to 52.47.255.25452.47.255.255131,070
2552.48.0.0/1552.48.0.1 to 52.49.255.25452.49.255.255131,070
2652.50.0.0/1552.50.0.1 to 52.51.255.25452.51.255.255131,070
2752.52.0.0/1552.52.0.1 to 52.53.255.25452.53.255.255131,070
2852.54.0.0/1552.54.0.1 to 52.55.255.25452.55.255.255131,070
2952.56.0.0/1552.56.0.1 to 52.57.255.25452.57.255.255131,070
3052.58.0.0/1552.58.0.1 to 52.59.255.25452.59.255.255131,070
3152.60.0.0/1552.60.0.1 to 52.61.255.25452.61.255.255131,070
3252.62.0.0/1552.62.0.1 to 52.63.255.25452.63.255.255131,070
3352.64.0.0/1552.64.0.1 to 52.65.255.25452.65.255.255131,070
3452.66.0.0/1552.66.0.1 to 52.67.255.25452.67.255.255131,070
3552.68.0.0/1552.68.0.1 to 52.69.255.25452.69.255.255131,070
3652.70.0.0/1552.70.0.1 to 52.71.255.25452.71.255.255131,070
3752.72.0.0/1552.72.0.1 to 52.73.255.25452.73.255.255131,070
3852.74.0.0/1552.74.0.1 to 52.75.255.25452.75.255.255131,070
3952.76.0.0/1552.76.0.1 to 52.77.255.25452.77.255.255131,070
4052.78.0.0/1552.78.0.1 to 52.79.255.25452.79.255.255131,070
4152.80.0.0/1552.80.0.1 to 52.81.255.25452.81.255.255131,070
4252.82.0.0/1552.82.0.1 to 52.83.255.25452.83.255.255131,070
4352.84.0.0/1552.84.0.1 to 52.85.255.25452.85.255.255131,070
4452.86.0.0/1552.86.0.1 to 52.87.255.25452.87.255.255131,070
4552.88.0.0/1552.88.0.1 to 52.89.255.25452.89.255.255131,070
4652.90.0.0/1552.90.0.1 to 52.91.255.25452.91.255.255131,070
4752.92.0.0/1552.92.0.1 to 52.93.255.25452.93.255.255131,070
4852.94.0.0/1552.94.0.1 to 52.95.255.25452.95.255.255131,070
4952.96.0.0/1552.96.0.1 to 52.97.255.25452.97.255.255131,070
5052.98.0.0/1552.98.0.1 to 52.99.255.25452.99.255.255131,070
5152.100.0.0/1552.100.0.1 to 52.101.255.25452.101.255.255131,070
5252.102.0.0/1552.102.0.1 to 52.103.255.25452.103.255.255131,070
5352.104.0.0/1552.104.0.1 to 52.105.255.25452.105.255.255131,070
5452.106.0.0/1552.106.0.1 to 52.107.255.25452.107.255.255131,070
5552.108.0.0/1552.108.0.1 to 52.109.255.25452.109.255.255131,070
5652.110.0.0/1552.110.0.1 to 52.111.255.25452.111.255.255131,070
5752.112.0.0/1552.112.0.1 to 52.113.255.25452.113.255.255131,070
5852.114.0.0/1552.114.0.1 to 52.115.255.25452.115.255.255131,070
5952.116.0.0/1552.116.0.1 to 52.117.255.25452.117.255.255131,070
6052.118.0.0/1552.118.0.1 to 52.119.255.25452.119.255.255131,070
6152.120.0.0/1552.120.0.1 to 52.121.255.25452.121.255.255131,070
6252.122.0.0/1552.122.0.1 to 52.123.255.25452.123.255.255131,070
6352.124.0.0/1552.124.0.1 to 52.125.255.25452.125.255.255131,070
6452.126.0.0/1552.126.0.1 to 52.127.255.25452.127.255.255131,070
6552.128.0.0/1552.128.0.1 to 52.129.255.25452.129.255.255131,070
6652.130.0.0/1552.130.0.1 to 52.131.255.25452.131.255.255131,070
6752.132.0.0/1552.132.0.1 to 52.133.255.25452.133.255.255131,070
6852.134.0.0/1552.134.0.1 to 52.135.255.25452.135.255.255131,070
6952.136.0.0/1552.136.0.1 to 52.137.255.25452.137.255.255131,070
7052.138.0.0/1552.138.0.1 to 52.139.255.25452.139.255.255131,070
7152.140.0.0/1552.140.0.1 to 52.141.255.25452.141.255.255131,070
7252.142.0.0/1552.142.0.1 to 52.143.255.25452.143.255.255131,070
7352.144.0.0/1552.144.0.1 to 52.145.255.25452.145.255.255131,070
7452.146.0.0/1552.146.0.1 to 52.147.255.25452.147.255.255131,070
7552.148.0.0/1552.148.0.1 to 52.149.255.25452.149.255.255131,070
7652.150.0.0/1552.150.0.1 to 52.151.255.25452.151.255.255131,070
7752.152.0.0/1552.152.0.1 to 52.153.255.25452.153.255.255131,070
7852.154.0.0/1552.154.0.1 to 52.155.255.25452.155.255.255131,070
7952.156.0.0/1552.156.0.1 to 52.157.255.25452.157.255.255131,070
8052.158.0.0/1552.158.0.1 to 52.159.255.25452.159.255.255131,070
8152.160.0.0/1552.160.0.1 to 52.161.255.25452.161.255.255131,070
8252.162.0.0/1552.162.0.1 to 52.163.255.25452.163.255.255131,070
8352.164.0.0/1552.164.0.1 to 52.165.255.25452.165.255.255131,070
8452.166.0.0/1552.166.0.1 to 52.167.255.25452.167.255.255131,070
8552.168.0.0/1552.168.0.1 to 52.169.255.25452.169.255.255131,070
8652.170.0.0/1552.170.0.1 to 52.171.255.25452.171.255.255131,070
8752.172.0.0/1552.172.0.1 to 52.173.255.25452.173.255.255131,070
8852.174.0.0/1552.174.0.1 to 52.175.255.25452.175.255.255131,070
8952.176.0.0/1552.176.0.1 to 52.177.255.25452.177.255.255131,070
9052.178.0.0/1552.178.0.1 to 52.179.255.25452.179.255.255131,070
9152.180.0.0/1552.180.0.1 to 52.181.255.25452.181.255.255131,070
9252.182.0.0/1552.182.0.1 to 52.183.255.25452.183.255.255131,070
9352.184.0.0/1552.184.0.1 to 52.185.255.25452.185.255.255131,070
9452.186.0.0/1552.186.0.1 to 52.187.255.25452.187.255.255131,070
9552.188.0.0/1552.188.0.1 to 52.189.255.25452.189.255.255131,070
9652.190.0.0/1552.190.0.1 to 52.191.255.25452.191.255.255131,070
9752.192.0.0/1552.192.0.1 to 52.193.255.25452.193.255.255131,070
9852.194.0.0/1552.194.0.1 to 52.195.255.25452.195.255.255131,070
9952.196.0.0/1552.196.0.1 to 52.197.255.25452.197.255.255131,070
10052.198.0.0/1552.198.0.1 to 52.199.255.25452.199.255.255131,070
10152.200.0.0/1552.200.0.1 to 52.201.255.25452.201.255.255131,070
10252.202.0.0/1552.202.0.1 to 52.203.255.25452.203.255.255131,070
10352.204.0.0/1552.204.0.1 to 52.205.255.25452.205.255.255131,070
10452.206.0.0/1552.206.0.1 to 52.207.255.25452.207.255.255131,070
10552.208.0.0/1552.208.0.1 to 52.209.255.25452.209.255.255131,070
10652.210.0.0/1552.210.0.1 to 52.211.255.25452.211.255.255131,070
10752.212.0.0/1552.212.0.1 to 52.213.255.25452.213.255.255131,070
10852.214.0.0/1552.214.0.1 to 52.215.255.25452.215.255.255131,070
10952.216.0.0/1552.216.0.1 to 52.217.255.25452.217.255.255131,070
11052.218.0.0/1552.218.0.1 to 52.219.255.25452.219.255.255131,070
11152.220.0.0/1552.220.0.1 to 52.221.255.25452.221.255.255131,070
11252.222.0.0/1552.222.0.1 to 52.223.255.25452.223.255.255131,070
11352.224.0.0/1552.224.0.1 to 52.225.255.25452.225.255.255131,070
11452.226.0.0/1552.226.0.1 to 52.227.255.25452.227.255.255131,070
11552.228.0.0/1552.228.0.1 to 52.229.255.25452.229.255.255131,070
11652.230.0.0/1552.230.0.1 to 52.231.255.25452.231.255.255131,070
11752.232.0.0/1552.232.0.1 to 52.233.255.25452.233.255.255131,070
11852.234.0.0/1552.234.0.1 to 52.235.255.25452.235.255.255131,070
11952.236.0.0/1552.236.0.1 to 52.237.255.25452.237.255.255131,070
12052.238.0.0/1552.238.0.1 to 52.239.255.25452.239.255.255131,070
12152.240.0.0/1552.240.0.1 to 52.241.255.25452.241.255.255131,070
12252.242.0.0/1552.242.0.1 to 52.243.255.25452.243.255.255131,070
12352.244.0.0/1552.244.0.1 to 52.245.255.25452.245.255.255131,070
12452.246.0.0/1552.246.0.1 to 52.247.255.25452.247.255.255131,070
12552.248.0.0/1552.248.0.1 to 52.249.255.25452.249.255.255131,070
12652.250.0.0/1552.250.0.1 to 52.251.255.25452.251.255.255131,070
12752.252.0.0/1552.252.0.1 to 52.253.255.25452.253.255.255131,070
12852.254.0.0/1552.254.0.1 to 52.255.255.25452.255.255.255131,070
12953.0.0.0/1553.0.0.1 to 53.1.255.25453.1.255.255131,070
13053.2.0.0/1553.2.0.1 to 53.3.255.25453.3.255.255131,070
13153.4.0.0/1553.4.0.1 to 53.5.255.25453.5.255.255131,070
13253.6.0.0/1553.6.0.1 to 53.7.255.25453.7.255.255131,070
13353.8.0.0/1553.8.0.1 to 53.9.255.25453.9.255.255131,070
13453.10.0.0/1553.10.0.1 to 53.11.255.25453.11.255.255131,070
13553.12.0.0/1553.12.0.1 to 53.13.255.25453.13.255.255131,070
13653.14.0.0/1553.14.0.1 to 53.15.255.25453.15.255.255131,070
13753.16.0.0/1553.16.0.1 to 53.17.255.25453.17.255.255131,070
13853.18.0.0/1553.18.0.1 to 53.19.255.25453.19.255.255131,070
13953.20.0.0/1553.20.0.1 to 53.21.255.25453.21.255.255131,070
14053.22.0.0/1553.22.0.1 to 53.23.255.25453.23.255.255131,070
14153.24.0.0/1553.24.0.1 to 53.25.255.25453.25.255.255131,070
14253.26.0.0/1553.26.0.1 to 53.27.255.25453.27.255.255131,070
14353.28.0.0/1553.28.0.1 to 53.29.255.25453.29.255.255131,070
14453.30.0.0/1553.30.0.1 to 53.31.255.25453.31.255.255131,070
14553.32.0.0/1553.32.0.1 to 53.33.255.25453.33.255.255131,070
14653.34.0.0/1553.34.0.1 to 53.35.255.25453.35.255.255131,070
14753.36.0.0/1553.36.0.1 to 53.37.255.25453.37.255.255131,070
14853.38.0.0/1553.38.0.1 to 53.39.255.25453.39.255.255131,070
14953.40.0.0/1553.40.0.1 to 53.41.255.25453.41.255.255131,070
15053.42.0.0/1553.42.0.1 to 53.43.255.25453.43.255.255131,070
15153.44.0.0/1553.44.0.1 to 53.45.255.25453.45.255.255131,070
15253.46.0.0/1553.46.0.1 to 53.47.255.25453.47.255.255131,070
15353.48.0.0/1553.48.0.1 to 53.49.255.25453.49.255.255131,070
15453.50.0.0/1553.50.0.1 to 53.51.255.25453.51.255.255131,070
15553.52.0.0/1553.52.0.1 to 53.53.255.25453.53.255.255131,070
15653.54.0.0/1553.54.0.1 to 53.55.255.25453.55.255.255131,070
15753.56.0.0/1553.56.0.1 to 53.57.255.25453.57.255.255131,070
15853.58.0.0/1553.58.0.1 to 53.59.255.25453.59.255.255131,070
15953.60.0.0/1553.60.0.1 to 53.61.255.25453.61.255.255131,070
16053.62.0.0/1553.62.0.1 to 53.63.255.25453.63.255.255131,070
16153.64.0.0/1553.64.0.1 to 53.65.255.25453.65.255.255131,070
16253.66.0.0/1553.66.0.1 to 53.67.255.25453.67.255.255131,070
16353.68.0.0/1553.68.0.1 to 53.69.255.25453.69.255.255131,070
16453.70.0.0/1553.70.0.1 to 53.71.255.25453.71.255.255131,070
16553.72.0.0/1553.72.0.1 to 53.73.255.25453.73.255.255131,070
16653.74.0.0/1553.74.0.1 to 53.75.255.25453.75.255.255131,070
16753.76.0.0/1553.76.0.1 to 53.77.255.25453.77.255.255131,070
16853.78.0.0/1553.78.0.1 to 53.79.255.25453.79.255.255131,070
16953.80.0.0/1553.80.0.1 to 53.81.255.25453.81.255.255131,070
17053.82.0.0/1553.82.0.1 to 53.83.255.25453.83.255.255131,070
17153.84.0.0/1553.84.0.1 to 53.85.255.25453.85.255.255131,070
17253.86.0.0/1553.86.0.1 to 53.87.255.25453.87.255.255131,070
17353.88.0.0/1553.88.0.1 to 53.89.255.25453.89.255.255131,070
17453.90.0.0/1553.90.0.1 to 53.91.255.25453.91.255.255131,070
17553.92.0.0/1553.92.0.1 to 53.93.255.25453.93.255.255131,070
17653.94.0.0/1553.94.0.1 to 53.95.255.25453.95.255.255131,070
17753.96.0.0/1553.96.0.1 to 53.97.255.25453.97.255.255131,070
17853.98.0.0/1553.98.0.1 to 53.99.255.25453.99.255.255131,070
17953.100.0.0/1553.100.0.1 to 53.101.255.25453.101.255.255131,070
18053.102.0.0/1553.102.0.1 to 53.103.255.25453.103.255.255131,070
18153.104.0.0/1553.104.0.1 to 53.105.255.25453.105.255.255131,070
18253.106.0.0/1553.106.0.1 to 53.107.255.25453.107.255.255131,070
18353.108.0.0/1553.108.0.1 to 53.109.255.25453.109.255.255131,070
18453.110.0.0/1553.110.0.1 to 53.111.255.25453.111.255.255131,070
18553.112.0.0/1553.112.0.1 to 53.113.255.25453.113.255.255131,070
18653.114.0.0/1553.114.0.1 to 53.115.255.25453.115.255.255131,070
18753.116.0.0/1553.116.0.1 to 53.117.255.25453.117.255.255131,070
18853.118.0.0/1553.118.0.1 to 53.119.255.25453.119.255.255131,070
18953.120.0.0/1553.120.0.1 to 53.121.255.25453.121.255.255131,070
19053.122.0.0/1553.122.0.1 to 53.123.255.25453.123.255.255131,070
19153.124.0.0/1553.124.0.1 to 53.125.255.25453.125.255.255131,070
19253.126.0.0/1553.126.0.1 to 53.127.255.25453.127.255.255131,070
19353.128.0.0/1553.128.0.1 to 53.129.255.25453.129.255.255131,070
19453.130.0.0/1553.130.0.1 to 53.131.255.25453.131.255.255131,070
19553.132.0.0/1553.132.0.1 to 53.133.255.25453.133.255.255131,070
19653.134.0.0/1553.134.0.1 to 53.135.255.25453.135.255.255131,070
19753.136.0.0/1553.136.0.1 to 53.137.255.25453.137.255.255131,070
19853.138.0.0/1553.138.0.1 to 53.139.255.25453.139.255.255131,070
19953.140.0.0/1553.140.0.1 to 53.141.255.25453.141.255.255131,070
20053.142.0.0/1553.142.0.1 to 53.143.255.25453.143.255.255131,070
20153.144.0.0/1553.144.0.1 to 53.145.255.25453.145.255.255131,070
20253.146.0.0/1553.146.0.1 to 53.147.255.25453.147.255.255131,070
20353.148.0.0/1553.148.0.1 to 53.149.255.25453.149.255.255131,070
20453.150.0.0/1553.150.0.1 to 53.151.255.25453.151.255.255131,070
20553.152.0.0/1553.152.0.1 to 53.153.255.25453.153.255.255131,070
20653.154.0.0/1553.154.0.1 to 53.155.255.25453.155.255.255131,070
20753.156.0.0/1553.156.0.1 to 53.157.255.25453.157.255.255131,070
20853.158.0.0/1553.158.0.1 to 53.159.255.25453.159.255.255131,070
20953.160.0.0/1553.160.0.1 to 53.161.255.25453.161.255.255131,070
21053.162.0.0/1553.162.0.1 to 53.163.255.25453.163.255.255131,070
21153.164.0.0/1553.164.0.1 to 53.165.255.25453.165.255.255131,070
21253.166.0.0/1553.166.0.1 to 53.167.255.25453.167.255.255131,070
21353.168.0.0/1553.168.0.1 to 53.169.255.25453.169.255.255131,070
21453.170.0.0/1553.170.0.1 to 53.171.255.25453.171.255.255131,070
21553.172.0.0/1553.172.0.1 to 53.173.255.25453.173.255.255131,070
21653.174.0.0/1553.174.0.1 to 53.175.255.25453.175.255.255131,070
21753.176.0.0/1553.176.0.1 to 53.177.255.25453.177.255.255131,070
21853.178.0.0/1553.178.0.1 to 53.179.255.25453.179.255.255131,070
21953.180.0.0/1553.180.0.1 to 53.181.255.25453.181.255.255131,070
22053.182.0.0/1553.182.0.1 to 53.183.255.25453.183.255.255131,070
22153.184.0.0/1553.184.0.1 to 53.185.255.25453.185.255.255131,070
22253.186.0.0/1553.186.0.1 to 53.187.255.25453.187.255.255131,070
22353.188.0.0/1553.188.0.1 to 53.189.255.25453.189.255.255131,070
22453.190.0.0/1553.190.0.1 to 53.191.255.25453.191.255.255131,070
22553.192.0.0/1553.192.0.1 to 53.193.255.25453.193.255.255131,070
22653.194.0.0/1553.194.0.1 to 53.195.255.25453.195.255.255131,070
22753.196.0.0/1553.196.0.1 to 53.197.255.25453.197.255.255131,070
22853.198.0.0/1553.198.0.1 to 53.199.255.25453.199.255.255131,070
22953.200.0.0/1553.200.0.1 to 53.201.255.25453.201.255.255131,070
23053.202.0.0/1553.202.0.1 to 53.203.255.25453.203.255.255131,070
23153.204.0.0/1553.204.0.1 to 53.205.255.25453.205.255.255131,070
23253.206.0.0/1553.206.0.1 to 53.207.255.25453.207.255.255131,070
23353.208.0.0/1553.208.0.1 to 53.209.255.25453.209.255.255131,070
23453.210.0.0/1553.210.0.1 to 53.211.255.25453.211.255.255131,070
23553.212.0.0/1553.212.0.1 to 53.213.255.25453.213.255.255131,070
23653.214.0.0/1553.214.0.1 to 53.215.255.25453.215.255.255131,070
23753.216.0.0/1553.216.0.1 to 53.217.255.25453.217.255.255131,070
23853.218.0.0/1553.218.0.1 to 53.219.255.25453.219.255.255131,070
23953.220.0.0/1553.220.0.1 to 53.221.255.25453.221.255.255131,070
24053.222.0.0/1553.222.0.1 to 53.223.255.25453.223.255.255131,070
24153.224.0.0/1553.224.0.1 to 53.225.255.25453.225.255.255131,070
24253.226.0.0/1553.226.0.1 to 53.227.255.25453.227.255.255131,070
24353.228.0.0/1553.228.0.1 to 53.229.255.25453.229.255.255131,070
24453.230.0.0/1553.230.0.1 to 53.231.255.25453.231.255.255131,070
24553.232.0.0/1553.232.0.1 to 53.233.255.25453.233.255.255131,070
24653.234.0.0/1553.234.0.1 to 53.235.255.25453.235.255.255131,070
24753.236.0.0/1553.236.0.1 to 53.237.255.25453.237.255.255131,070
24853.238.0.0/1553.238.0.1 to 53.239.255.25453.239.255.255131,070
24953.240.0.0/1553.240.0.1 to 53.241.255.25453.241.255.255131,070
25053.242.0.0/1553.242.0.1 to 53.243.255.25453.243.255.255131,070
25153.244.0.0/1553.244.0.1 to 53.245.255.25453.245.255.255131,070
25253.246.0.0/1553.246.0.1 to 53.247.255.25453.247.255.255131,070
25353.248.0.0/1553.248.0.1 to 53.249.255.25453.249.255.255131,070
25453.250.0.0/1553.250.0.1 to 53.251.255.25453.251.255.255131,070
25553.252.0.0/1553.252.0.1 to 53.253.255.25453.253.255.255131,070
25653.254.0.0/1553.254.0.1 to 53.255.255.25453.255.255.255131,070

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.