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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/14
/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 256 subnets of /14.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
152.0.0.0/1452.0.0.1 to 52.3.255.25452.3.255.255262,142
252.4.0.0/1452.4.0.1 to 52.7.255.25452.7.255.255262,142
352.8.0.0/1452.8.0.1 to 52.11.255.25452.11.255.255262,142
452.12.0.0/1452.12.0.1 to 52.15.255.25452.15.255.255262,142
552.16.0.0/1452.16.0.1 to 52.19.255.25452.19.255.255262,142
652.20.0.0/1452.20.0.1 to 52.23.255.25452.23.255.255262,142
752.24.0.0/1452.24.0.1 to 52.27.255.25452.27.255.255262,142
852.28.0.0/1452.28.0.1 to 52.31.255.25452.31.255.255262,142
952.32.0.0/1452.32.0.1 to 52.35.255.25452.35.255.255262,142
1052.36.0.0/1452.36.0.1 to 52.39.255.25452.39.255.255262,142
1152.40.0.0/1452.40.0.1 to 52.43.255.25452.43.255.255262,142
1252.44.0.0/1452.44.0.1 to 52.47.255.25452.47.255.255262,142
1352.48.0.0/1452.48.0.1 to 52.51.255.25452.51.255.255262,142
1452.52.0.0/1452.52.0.1 to 52.55.255.25452.55.255.255262,142
1552.56.0.0/1452.56.0.1 to 52.59.255.25452.59.255.255262,142
1652.60.0.0/1452.60.0.1 to 52.63.255.25452.63.255.255262,142
1752.64.0.0/1452.64.0.1 to 52.67.255.25452.67.255.255262,142
1852.68.0.0/1452.68.0.1 to 52.71.255.25452.71.255.255262,142
1952.72.0.0/1452.72.0.1 to 52.75.255.25452.75.255.255262,142
2052.76.0.0/1452.76.0.1 to 52.79.255.25452.79.255.255262,142
2152.80.0.0/1452.80.0.1 to 52.83.255.25452.83.255.255262,142
2252.84.0.0/1452.84.0.1 to 52.87.255.25452.87.255.255262,142
2352.88.0.0/1452.88.0.1 to 52.91.255.25452.91.255.255262,142
2452.92.0.0/1452.92.0.1 to 52.95.255.25452.95.255.255262,142
2552.96.0.0/1452.96.0.1 to 52.99.255.25452.99.255.255262,142
2652.100.0.0/1452.100.0.1 to 52.103.255.25452.103.255.255262,142
2752.104.0.0/1452.104.0.1 to 52.107.255.25452.107.255.255262,142
2852.108.0.0/1452.108.0.1 to 52.111.255.25452.111.255.255262,142
2952.112.0.0/1452.112.0.1 to 52.115.255.25452.115.255.255262,142
3052.116.0.0/1452.116.0.1 to 52.119.255.25452.119.255.255262,142
3152.120.0.0/1452.120.0.1 to 52.123.255.25452.123.255.255262,142
3252.124.0.0/1452.124.0.1 to 52.127.255.25452.127.255.255262,142
3352.128.0.0/1452.128.0.1 to 52.131.255.25452.131.255.255262,142
3452.132.0.0/1452.132.0.1 to 52.135.255.25452.135.255.255262,142
3552.136.0.0/1452.136.0.1 to 52.139.255.25452.139.255.255262,142
3652.140.0.0/1452.140.0.1 to 52.143.255.25452.143.255.255262,142
3752.144.0.0/1452.144.0.1 to 52.147.255.25452.147.255.255262,142
3852.148.0.0/1452.148.0.1 to 52.151.255.25452.151.255.255262,142
3952.152.0.0/1452.152.0.1 to 52.155.255.25452.155.255.255262,142
4052.156.0.0/1452.156.0.1 to 52.159.255.25452.159.255.255262,142
4152.160.0.0/1452.160.0.1 to 52.163.255.25452.163.255.255262,142
4252.164.0.0/1452.164.0.1 to 52.167.255.25452.167.255.255262,142
4352.168.0.0/1452.168.0.1 to 52.171.255.25452.171.255.255262,142
4452.172.0.0/1452.172.0.1 to 52.175.255.25452.175.255.255262,142
4552.176.0.0/1452.176.0.1 to 52.179.255.25452.179.255.255262,142
4652.180.0.0/1452.180.0.1 to 52.183.255.25452.183.255.255262,142
4752.184.0.0/1452.184.0.1 to 52.187.255.25452.187.255.255262,142
4852.188.0.0/1452.188.0.1 to 52.191.255.25452.191.255.255262,142
4952.192.0.0/1452.192.0.1 to 52.195.255.25452.195.255.255262,142
5052.196.0.0/1452.196.0.1 to 52.199.255.25452.199.255.255262,142
5152.200.0.0/1452.200.0.1 to 52.203.255.25452.203.255.255262,142
5252.204.0.0/1452.204.0.1 to 52.207.255.25452.207.255.255262,142
5352.208.0.0/1452.208.0.1 to 52.211.255.25452.211.255.255262,142
5452.212.0.0/1452.212.0.1 to 52.215.255.25452.215.255.255262,142
5552.216.0.0/1452.216.0.1 to 52.219.255.25452.219.255.255262,142
5652.220.0.0/1452.220.0.1 to 52.223.255.25452.223.255.255262,142
5752.224.0.0/1452.224.0.1 to 52.227.255.25452.227.255.255262,142
5852.228.0.0/1452.228.0.1 to 52.231.255.25452.231.255.255262,142
5952.232.0.0/1452.232.0.1 to 52.235.255.25452.235.255.255262,142
6052.236.0.0/1452.236.0.1 to 52.239.255.25452.239.255.255262,142
6152.240.0.0/1452.240.0.1 to 52.243.255.25452.243.255.255262,142
6252.244.0.0/1452.244.0.1 to 52.247.255.25452.247.255.255262,142
6352.248.0.0/1452.248.0.1 to 52.251.255.25452.251.255.255262,142
6452.252.0.0/1452.252.0.1 to 52.255.255.25452.255.255.255262,142
6553.0.0.0/1453.0.0.1 to 53.3.255.25453.3.255.255262,142
6653.4.0.0/1453.4.0.1 to 53.7.255.25453.7.255.255262,142
6753.8.0.0/1453.8.0.1 to 53.11.255.25453.11.255.255262,142
6853.12.0.0/1453.12.0.1 to 53.15.255.25453.15.255.255262,142
6953.16.0.0/1453.16.0.1 to 53.19.255.25453.19.255.255262,142
7053.20.0.0/1453.20.0.1 to 53.23.255.25453.23.255.255262,142
7153.24.0.0/1453.24.0.1 to 53.27.255.25453.27.255.255262,142
7253.28.0.0/1453.28.0.1 to 53.31.255.25453.31.255.255262,142
7353.32.0.0/1453.32.0.1 to 53.35.255.25453.35.255.255262,142
7453.36.0.0/1453.36.0.1 to 53.39.255.25453.39.255.255262,142
7553.40.0.0/1453.40.0.1 to 53.43.255.25453.43.255.255262,142
7653.44.0.0/1453.44.0.1 to 53.47.255.25453.47.255.255262,142
7753.48.0.0/1453.48.0.1 to 53.51.255.25453.51.255.255262,142
7853.52.0.0/1453.52.0.1 to 53.55.255.25453.55.255.255262,142
7953.56.0.0/1453.56.0.1 to 53.59.255.25453.59.255.255262,142
8053.60.0.0/1453.60.0.1 to 53.63.255.25453.63.255.255262,142
8153.64.0.0/1453.64.0.1 to 53.67.255.25453.67.255.255262,142
8253.68.0.0/1453.68.0.1 to 53.71.255.25453.71.255.255262,142
8353.72.0.0/1453.72.0.1 to 53.75.255.25453.75.255.255262,142
8453.76.0.0/1453.76.0.1 to 53.79.255.25453.79.255.255262,142
8553.80.0.0/1453.80.0.1 to 53.83.255.25453.83.255.255262,142
8653.84.0.0/1453.84.0.1 to 53.87.255.25453.87.255.255262,142
8753.88.0.0/1453.88.0.1 to 53.91.255.25453.91.255.255262,142
8853.92.0.0/1453.92.0.1 to 53.95.255.25453.95.255.255262,142
8953.96.0.0/1453.96.0.1 to 53.99.255.25453.99.255.255262,142
9053.100.0.0/1453.100.0.1 to 53.103.255.25453.103.255.255262,142
9153.104.0.0/1453.104.0.1 to 53.107.255.25453.107.255.255262,142
9253.108.0.0/1453.108.0.1 to 53.111.255.25453.111.255.255262,142
9353.112.0.0/1453.112.0.1 to 53.115.255.25453.115.255.255262,142
9453.116.0.0/1453.116.0.1 to 53.119.255.25453.119.255.255262,142
9553.120.0.0/1453.120.0.1 to 53.123.255.25453.123.255.255262,142
9653.124.0.0/1453.124.0.1 to 53.127.255.25453.127.255.255262,142
9753.128.0.0/1453.128.0.1 to 53.131.255.25453.131.255.255262,142
9853.132.0.0/1453.132.0.1 to 53.135.255.25453.135.255.255262,142
9953.136.0.0/1453.136.0.1 to 53.139.255.25453.139.255.255262,142
10053.140.0.0/1453.140.0.1 to 53.143.255.25453.143.255.255262,142
10153.144.0.0/1453.144.0.1 to 53.147.255.25453.147.255.255262,142
10253.148.0.0/1453.148.0.1 to 53.151.255.25453.151.255.255262,142
10353.152.0.0/1453.152.0.1 to 53.155.255.25453.155.255.255262,142
10453.156.0.0/1453.156.0.1 to 53.159.255.25453.159.255.255262,142
10553.160.0.0/1453.160.0.1 to 53.163.255.25453.163.255.255262,142
10653.164.0.0/1453.164.0.1 to 53.167.255.25453.167.255.255262,142
10753.168.0.0/1453.168.0.1 to 53.171.255.25453.171.255.255262,142
10853.172.0.0/1453.172.0.1 to 53.175.255.25453.175.255.255262,142
10953.176.0.0/1453.176.0.1 to 53.179.255.25453.179.255.255262,142
11053.180.0.0/1453.180.0.1 to 53.183.255.25453.183.255.255262,142
11153.184.0.0/1453.184.0.1 to 53.187.255.25453.187.255.255262,142
11253.188.0.0/1453.188.0.1 to 53.191.255.25453.191.255.255262,142
11353.192.0.0/1453.192.0.1 to 53.195.255.25453.195.255.255262,142
11453.196.0.0/1453.196.0.1 to 53.199.255.25453.199.255.255262,142
11553.200.0.0/1453.200.0.1 to 53.203.255.25453.203.255.255262,142
11653.204.0.0/1453.204.0.1 to 53.207.255.25453.207.255.255262,142
11753.208.0.0/1453.208.0.1 to 53.211.255.25453.211.255.255262,142
11853.212.0.0/1453.212.0.1 to 53.215.255.25453.215.255.255262,142
11953.216.0.0/1453.216.0.1 to 53.219.255.25453.219.255.255262,142
12053.220.0.0/1453.220.0.1 to 53.223.255.25453.223.255.255262,142
12153.224.0.0/1453.224.0.1 to 53.227.255.25453.227.255.255262,142
12253.228.0.0/1453.228.0.1 to 53.231.255.25453.231.255.255262,142
12353.232.0.0/1453.232.0.1 to 53.235.255.25453.235.255.255262,142
12453.236.0.0/1453.236.0.1 to 53.239.255.25453.239.255.255262,142
12553.240.0.0/1453.240.0.1 to 53.243.255.25453.243.255.255262,142
12653.244.0.0/1453.244.0.1 to 53.247.255.25453.247.255.255262,142
12753.248.0.0/1453.248.0.1 to 53.251.255.25453.251.255.255262,142
12853.252.0.0/1453.252.0.1 to 53.255.255.25453.255.255.255262,142
12954.0.0.0/1454.0.0.1 to 54.3.255.25454.3.255.255262,142
13054.4.0.0/1454.4.0.1 to 54.7.255.25454.7.255.255262,142
13154.8.0.0/1454.8.0.1 to 54.11.255.25454.11.255.255262,142
13254.12.0.0/1454.12.0.1 to 54.15.255.25454.15.255.255262,142
13354.16.0.0/1454.16.0.1 to 54.19.255.25454.19.255.255262,142
13454.20.0.0/1454.20.0.1 to 54.23.255.25454.23.255.255262,142
13554.24.0.0/1454.24.0.1 to 54.27.255.25454.27.255.255262,142
13654.28.0.0/1454.28.0.1 to 54.31.255.25454.31.255.255262,142
13754.32.0.0/1454.32.0.1 to 54.35.255.25454.35.255.255262,142
13854.36.0.0/1454.36.0.1 to 54.39.255.25454.39.255.255262,142
13954.40.0.0/1454.40.0.1 to 54.43.255.25454.43.255.255262,142
14054.44.0.0/1454.44.0.1 to 54.47.255.25454.47.255.255262,142
14154.48.0.0/1454.48.0.1 to 54.51.255.25454.51.255.255262,142
14254.52.0.0/1454.52.0.1 to 54.55.255.25454.55.255.255262,142
14354.56.0.0/1454.56.0.1 to 54.59.255.25454.59.255.255262,142
14454.60.0.0/1454.60.0.1 to 54.63.255.25454.63.255.255262,142
14554.64.0.0/1454.64.0.1 to 54.67.255.25454.67.255.255262,142
14654.68.0.0/1454.68.0.1 to 54.71.255.25454.71.255.255262,142
14754.72.0.0/1454.72.0.1 to 54.75.255.25454.75.255.255262,142
14854.76.0.0/1454.76.0.1 to 54.79.255.25454.79.255.255262,142
14954.80.0.0/1454.80.0.1 to 54.83.255.25454.83.255.255262,142
15054.84.0.0/1454.84.0.1 to 54.87.255.25454.87.255.255262,142
15154.88.0.0/1454.88.0.1 to 54.91.255.25454.91.255.255262,142
15254.92.0.0/1454.92.0.1 to 54.95.255.25454.95.255.255262,142
15354.96.0.0/1454.96.0.1 to 54.99.255.25454.99.255.255262,142
15454.100.0.0/1454.100.0.1 to 54.103.255.25454.103.255.255262,142
15554.104.0.0/1454.104.0.1 to 54.107.255.25454.107.255.255262,142
15654.108.0.0/1454.108.0.1 to 54.111.255.25454.111.255.255262,142
15754.112.0.0/1454.112.0.1 to 54.115.255.25454.115.255.255262,142
15854.116.0.0/1454.116.0.1 to 54.119.255.25454.119.255.255262,142
15954.120.0.0/1454.120.0.1 to 54.123.255.25454.123.255.255262,142
16054.124.0.0/1454.124.0.1 to 54.127.255.25454.127.255.255262,142
16154.128.0.0/1454.128.0.1 to 54.131.255.25454.131.255.255262,142
16254.132.0.0/1454.132.0.1 to 54.135.255.25454.135.255.255262,142
16354.136.0.0/1454.136.0.1 to 54.139.255.25454.139.255.255262,142
16454.140.0.0/1454.140.0.1 to 54.143.255.25454.143.255.255262,142
16554.144.0.0/1454.144.0.1 to 54.147.255.25454.147.255.255262,142
16654.148.0.0/1454.148.0.1 to 54.151.255.25454.151.255.255262,142
16754.152.0.0/1454.152.0.1 to 54.155.255.25454.155.255.255262,142
16854.156.0.0/1454.156.0.1 to 54.159.255.25454.159.255.255262,142
16954.160.0.0/1454.160.0.1 to 54.163.255.25454.163.255.255262,142
17054.164.0.0/1454.164.0.1 to 54.167.255.25454.167.255.255262,142
17154.168.0.0/1454.168.0.1 to 54.171.255.25454.171.255.255262,142
17254.172.0.0/1454.172.0.1 to 54.175.255.25454.175.255.255262,142
17354.176.0.0/1454.176.0.1 to 54.179.255.25454.179.255.255262,142
17454.180.0.0/1454.180.0.1 to 54.183.255.25454.183.255.255262,142
17554.184.0.0/1454.184.0.1 to 54.187.255.25454.187.255.255262,142
17654.188.0.0/1454.188.0.1 to 54.191.255.25454.191.255.255262,142
17754.192.0.0/1454.192.0.1 to 54.195.255.25454.195.255.255262,142
17854.196.0.0/1454.196.0.1 to 54.199.255.25454.199.255.255262,142
17954.200.0.0/1454.200.0.1 to 54.203.255.25454.203.255.255262,142
18054.204.0.0/1454.204.0.1 to 54.207.255.25454.207.255.255262,142
18154.208.0.0/1454.208.0.1 to 54.211.255.25454.211.255.255262,142
18254.212.0.0/1454.212.0.1 to 54.215.255.25454.215.255.255262,142
18354.216.0.0/1454.216.0.1 to 54.219.255.25454.219.255.255262,142
18454.220.0.0/1454.220.0.1 to 54.223.255.25454.223.255.255262,142
18554.224.0.0/1454.224.0.1 to 54.227.255.25454.227.255.255262,142
18654.228.0.0/1454.228.0.1 to 54.231.255.25454.231.255.255262,142
18754.232.0.0/1454.232.0.1 to 54.235.255.25454.235.255.255262,142
18854.236.0.0/1454.236.0.1 to 54.239.255.25454.239.255.255262,142
18954.240.0.0/1454.240.0.1 to 54.243.255.25454.243.255.255262,142
19054.244.0.0/1454.244.0.1 to 54.247.255.25454.247.255.255262,142
19154.248.0.0/1454.248.0.1 to 54.251.255.25454.251.255.255262,142
19254.252.0.0/1454.252.0.1 to 54.255.255.25454.255.255.255262,142
19355.0.0.0/1455.0.0.1 to 55.3.255.25455.3.255.255262,142
19455.4.0.0/1455.4.0.1 to 55.7.255.25455.7.255.255262,142
19555.8.0.0/1455.8.0.1 to 55.11.255.25455.11.255.255262,142
19655.12.0.0/1455.12.0.1 to 55.15.255.25455.15.255.255262,142
19755.16.0.0/1455.16.0.1 to 55.19.255.25455.19.255.255262,142
19855.20.0.0/1455.20.0.1 to 55.23.255.25455.23.255.255262,142
19955.24.0.0/1455.24.0.1 to 55.27.255.25455.27.255.255262,142
20055.28.0.0/1455.28.0.1 to 55.31.255.25455.31.255.255262,142
20155.32.0.0/1455.32.0.1 to 55.35.255.25455.35.255.255262,142
20255.36.0.0/1455.36.0.1 to 55.39.255.25455.39.255.255262,142
20355.40.0.0/1455.40.0.1 to 55.43.255.25455.43.255.255262,142
20455.44.0.0/1455.44.0.1 to 55.47.255.25455.47.255.255262,142
20555.48.0.0/1455.48.0.1 to 55.51.255.25455.51.255.255262,142
20655.52.0.0/1455.52.0.1 to 55.55.255.25455.55.255.255262,142
20755.56.0.0/1455.56.0.1 to 55.59.255.25455.59.255.255262,142
20855.60.0.0/1455.60.0.1 to 55.63.255.25455.63.255.255262,142
20955.64.0.0/1455.64.0.1 to 55.67.255.25455.67.255.255262,142
21055.68.0.0/1455.68.0.1 to 55.71.255.25455.71.255.255262,142
21155.72.0.0/1455.72.0.1 to 55.75.255.25455.75.255.255262,142
21255.76.0.0/1455.76.0.1 to 55.79.255.25455.79.255.255262,142
21355.80.0.0/1455.80.0.1 to 55.83.255.25455.83.255.255262,142
21455.84.0.0/1455.84.0.1 to 55.87.255.25455.87.255.255262,142
21555.88.0.0/1455.88.0.1 to 55.91.255.25455.91.255.255262,142
21655.92.0.0/1455.92.0.1 to 55.95.255.25455.95.255.255262,142
21755.96.0.0/1455.96.0.1 to 55.99.255.25455.99.255.255262,142
21855.100.0.0/1455.100.0.1 to 55.103.255.25455.103.255.255262,142
21955.104.0.0/1455.104.0.1 to 55.107.255.25455.107.255.255262,142
22055.108.0.0/1455.108.0.1 to 55.111.255.25455.111.255.255262,142
22155.112.0.0/1455.112.0.1 to 55.115.255.25455.115.255.255262,142
22255.116.0.0/1455.116.0.1 to 55.119.255.25455.119.255.255262,142
22355.120.0.0/1455.120.0.1 to 55.123.255.25455.123.255.255262,142
22455.124.0.0/1455.124.0.1 to 55.127.255.25455.127.255.255262,142
22555.128.0.0/1455.128.0.1 to 55.131.255.25455.131.255.255262,142
22655.132.0.0/1455.132.0.1 to 55.135.255.25455.135.255.255262,142
22755.136.0.0/1455.136.0.1 to 55.139.255.25455.139.255.255262,142
22855.140.0.0/1455.140.0.1 to 55.143.255.25455.143.255.255262,142
22955.144.0.0/1455.144.0.1 to 55.147.255.25455.147.255.255262,142
23055.148.0.0/1455.148.0.1 to 55.151.255.25455.151.255.255262,142
23155.152.0.0/1455.152.0.1 to 55.155.255.25455.155.255.255262,142
23255.156.0.0/1455.156.0.1 to 55.159.255.25455.159.255.255262,142
23355.160.0.0/1455.160.0.1 to 55.163.255.25455.163.255.255262,142
23455.164.0.0/1455.164.0.1 to 55.167.255.25455.167.255.255262,142
23555.168.0.0/1455.168.0.1 to 55.171.255.25455.171.255.255262,142
23655.172.0.0/1455.172.0.1 to 55.175.255.25455.175.255.255262,142
23755.176.0.0/1455.176.0.1 to 55.179.255.25455.179.255.255262,142
23855.180.0.0/1455.180.0.1 to 55.183.255.25455.183.255.255262,142
23955.184.0.0/1455.184.0.1 to 55.187.255.25455.187.255.255262,142
24055.188.0.0/1455.188.0.1 to 55.191.255.25455.191.255.255262,142
24155.192.0.0/1455.192.0.1 to 55.195.255.25455.195.255.255262,142
24255.196.0.0/1455.196.0.1 to 55.199.255.25455.199.255.255262,142
24355.200.0.0/1455.200.0.1 to 55.203.255.25455.203.255.255262,142
24455.204.0.0/1455.204.0.1 to 55.207.255.25455.207.255.255262,142
24555.208.0.0/1455.208.0.1 to 55.211.255.25455.211.255.255262,142
24655.212.0.0/1455.212.0.1 to 55.215.255.25455.215.255.255262,142
24755.216.0.0/1455.216.0.1 to 55.219.255.25455.219.255.255262,142
24855.220.0.0/1455.220.0.1 to 55.223.255.25455.223.255.255262,142
24955.224.0.0/1455.224.0.1 to 55.227.255.25455.227.255.255262,142
25055.228.0.0/1455.228.0.1 to 55.231.255.25455.231.255.255262,142
25155.232.0.0/1455.232.0.1 to 55.235.255.25455.235.255.255262,142
25255.236.0.0/1455.236.0.1 to 55.239.255.25455.239.255.255262,142
25355.240.0.0/1455.240.0.1 to 55.243.255.25455.243.255.255262,142
25455.244.0.0/1455.244.0.1 to 55.247.255.25455.247.255.255262,142
25555.248.0.0/1455.248.0.1 to 55.251.255.25455.251.255.255262,142
25655.252.0.0/1455.252.0.1 to 55.255.255.25455.255.255.255262,142

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.