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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.

Network53.64.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
53.64.0.0
Broadcast address
53.127.255.255
First usable
53.64.0.1
Last usable
53.127.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Public public
Old class
A (default /8)
As numbers
Hex 35400000 · Integer 893386752 to 897581055
Reverse DNS zones
64.53.in-addr.arpa
65.53.in-addr.arpa
66.53.in-addr.arpa
67.53.in-addr.arpa
68.53.in-addr.arpa
69.53.in-addr.arpa
70.53.in-addr.arpa
71.53.in-addr.arpa
72.53.in-addr.arpa
73.53.in-addr.arpa
74.53.in-addr.arpa
75.53.in-addr.arpa
76.53.in-addr.arpa
77.53.in-addr.arpa
78.53.in-addr.arpa
79.53.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110101.01000000.00000000.0000000053.64.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00110101.01000000.00000000.0000000053.64.0.0
Broadcast00110101.01111111.11111111.1111111153.127.255.255
Split into smaller subnets/22
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

53.64.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
153.64.0.0/2253.64.0.1 to 53.64.3.25453.64.3.2551,022
253.64.4.0/2253.64.4.1 to 53.64.7.25453.64.7.2551,022
353.64.8.0/2253.64.8.1 to 53.64.11.25453.64.11.2551,022
453.64.12.0/2253.64.12.1 to 53.64.15.25453.64.15.2551,022
553.64.16.0/2253.64.16.1 to 53.64.19.25453.64.19.2551,022
653.64.20.0/2253.64.20.1 to 53.64.23.25453.64.23.2551,022
753.64.24.0/2253.64.24.1 to 53.64.27.25453.64.27.2551,022
853.64.28.0/2253.64.28.1 to 53.64.31.25453.64.31.2551,022
953.64.32.0/2253.64.32.1 to 53.64.35.25453.64.35.2551,022
1053.64.36.0/2253.64.36.1 to 53.64.39.25453.64.39.2551,022
1153.64.40.0/2253.64.40.1 to 53.64.43.25453.64.43.2551,022
1253.64.44.0/2253.64.44.1 to 53.64.47.25453.64.47.2551,022
1353.64.48.0/2253.64.48.1 to 53.64.51.25453.64.51.2551,022
1453.64.52.0/2253.64.52.1 to 53.64.55.25453.64.55.2551,022
1553.64.56.0/2253.64.56.1 to 53.64.59.25453.64.59.2551,022
1653.64.60.0/2253.64.60.1 to 53.64.63.25453.64.63.2551,022
1753.64.64.0/2253.64.64.1 to 53.64.67.25453.64.67.2551,022
1853.64.68.0/2253.64.68.1 to 53.64.71.25453.64.71.2551,022
1953.64.72.0/2253.64.72.1 to 53.64.75.25453.64.75.2551,022
2053.64.76.0/2253.64.76.1 to 53.64.79.25453.64.79.2551,022
2153.64.80.0/2253.64.80.1 to 53.64.83.25453.64.83.2551,022
2253.64.84.0/2253.64.84.1 to 53.64.87.25453.64.87.2551,022
2353.64.88.0/2253.64.88.1 to 53.64.91.25453.64.91.2551,022
2453.64.92.0/2253.64.92.1 to 53.64.95.25453.64.95.2551,022
2553.64.96.0/2253.64.96.1 to 53.64.99.25453.64.99.2551,022
2653.64.100.0/2253.64.100.1 to 53.64.103.25453.64.103.2551,022
2753.64.104.0/2253.64.104.1 to 53.64.107.25453.64.107.2551,022
2853.64.108.0/2253.64.108.1 to 53.64.111.25453.64.111.2551,022
2953.64.112.0/2253.64.112.1 to 53.64.115.25453.64.115.2551,022
3053.64.116.0/2253.64.116.1 to 53.64.119.25453.64.119.2551,022
3153.64.120.0/2253.64.120.1 to 53.64.123.25453.64.123.2551,022
3253.64.124.0/2253.64.124.1 to 53.64.127.25453.64.127.2551,022
3353.64.128.0/2253.64.128.1 to 53.64.131.25453.64.131.2551,022
3453.64.132.0/2253.64.132.1 to 53.64.135.25453.64.135.2551,022
3553.64.136.0/2253.64.136.1 to 53.64.139.25453.64.139.2551,022
3653.64.140.0/2253.64.140.1 to 53.64.143.25453.64.143.2551,022
3753.64.144.0/2253.64.144.1 to 53.64.147.25453.64.147.2551,022
3853.64.148.0/2253.64.148.1 to 53.64.151.25453.64.151.2551,022
3953.64.152.0/2253.64.152.1 to 53.64.155.25453.64.155.2551,022
4053.64.156.0/2253.64.156.1 to 53.64.159.25453.64.159.2551,022
4153.64.160.0/2253.64.160.1 to 53.64.163.25453.64.163.2551,022
4253.64.164.0/2253.64.164.1 to 53.64.167.25453.64.167.2551,022
4353.64.168.0/2253.64.168.1 to 53.64.171.25453.64.171.2551,022
4453.64.172.0/2253.64.172.1 to 53.64.175.25453.64.175.2551,022
4553.64.176.0/2253.64.176.1 to 53.64.179.25453.64.179.2551,022
4653.64.180.0/2253.64.180.1 to 53.64.183.25453.64.183.2551,022
4753.64.184.0/2253.64.184.1 to 53.64.187.25453.64.187.2551,022
4853.64.188.0/2253.64.188.1 to 53.64.191.25453.64.191.2551,022
4953.64.192.0/2253.64.192.1 to 53.64.195.25453.64.195.2551,022
5053.64.196.0/2253.64.196.1 to 53.64.199.25453.64.199.2551,022
5153.64.200.0/2253.64.200.1 to 53.64.203.25453.64.203.2551,022
5253.64.204.0/2253.64.204.1 to 53.64.207.25453.64.207.2551,022
5353.64.208.0/2253.64.208.1 to 53.64.211.25453.64.211.2551,022
5453.64.212.0/2253.64.212.1 to 53.64.215.25453.64.215.2551,022
5553.64.216.0/2253.64.216.1 to 53.64.219.25453.64.219.2551,022
5653.64.220.0/2253.64.220.1 to 53.64.223.25453.64.223.2551,022
5753.64.224.0/2253.64.224.1 to 53.64.227.25453.64.227.2551,022
5853.64.228.0/2253.64.228.1 to 53.64.231.25453.64.231.2551,022
5953.64.232.0/2253.64.232.1 to 53.64.235.25453.64.235.2551,022
6053.64.236.0/2253.64.236.1 to 53.64.239.25453.64.239.2551,022
6153.64.240.0/2253.64.240.1 to 53.64.243.25453.64.243.2551,022
6253.64.244.0/2253.64.244.1 to 53.64.247.25453.64.247.2551,022
6353.64.248.0/2253.64.248.1 to 53.64.251.25453.64.251.2551,022
6453.64.252.0/2253.64.252.1 to 53.64.255.25453.64.255.2551,022
6553.65.0.0/2253.65.0.1 to 53.65.3.25453.65.3.2551,022
6653.65.4.0/2253.65.4.1 to 53.65.7.25453.65.7.2551,022
6753.65.8.0/2253.65.8.1 to 53.65.11.25453.65.11.2551,022
6853.65.12.0/2253.65.12.1 to 53.65.15.25453.65.15.2551,022
6953.65.16.0/2253.65.16.1 to 53.65.19.25453.65.19.2551,022
7053.65.20.0/2253.65.20.1 to 53.65.23.25453.65.23.2551,022
7153.65.24.0/2253.65.24.1 to 53.65.27.25453.65.27.2551,022
7253.65.28.0/2253.65.28.1 to 53.65.31.25453.65.31.2551,022
7353.65.32.0/2253.65.32.1 to 53.65.35.25453.65.35.2551,022
7453.65.36.0/2253.65.36.1 to 53.65.39.25453.65.39.2551,022
7553.65.40.0/2253.65.40.1 to 53.65.43.25453.65.43.2551,022
7653.65.44.0/2253.65.44.1 to 53.65.47.25453.65.47.2551,022
7753.65.48.0/2253.65.48.1 to 53.65.51.25453.65.51.2551,022
7853.65.52.0/2253.65.52.1 to 53.65.55.25453.65.55.2551,022
7953.65.56.0/2253.65.56.1 to 53.65.59.25453.65.59.2551,022
8053.65.60.0/2253.65.60.1 to 53.65.63.25453.65.63.2551,022
8153.65.64.0/2253.65.64.1 to 53.65.67.25453.65.67.2551,022
8253.65.68.0/2253.65.68.1 to 53.65.71.25453.65.71.2551,022
8353.65.72.0/2253.65.72.1 to 53.65.75.25453.65.75.2551,022
8453.65.76.0/2253.65.76.1 to 53.65.79.25453.65.79.2551,022
8553.65.80.0/2253.65.80.1 to 53.65.83.25453.65.83.2551,022
8653.65.84.0/2253.65.84.1 to 53.65.87.25453.65.87.2551,022
8753.65.88.0/2253.65.88.1 to 53.65.91.25453.65.91.2551,022
8853.65.92.0/2253.65.92.1 to 53.65.95.25453.65.95.2551,022
8953.65.96.0/2253.65.96.1 to 53.65.99.25453.65.99.2551,022
9053.65.100.0/2253.65.100.1 to 53.65.103.25453.65.103.2551,022
9153.65.104.0/2253.65.104.1 to 53.65.107.25453.65.107.2551,022
9253.65.108.0/2253.65.108.1 to 53.65.111.25453.65.111.2551,022
9353.65.112.0/2253.65.112.1 to 53.65.115.25453.65.115.2551,022
9453.65.116.0/2253.65.116.1 to 53.65.119.25453.65.119.2551,022
9553.65.120.0/2253.65.120.1 to 53.65.123.25453.65.123.2551,022
9653.65.124.0/2253.65.124.1 to 53.65.127.25453.65.127.2551,022
9753.65.128.0/2253.65.128.1 to 53.65.131.25453.65.131.2551,022
9853.65.132.0/2253.65.132.1 to 53.65.135.25453.65.135.2551,022
9953.65.136.0/2253.65.136.1 to 53.65.139.25453.65.139.2551,022
10053.65.140.0/2253.65.140.1 to 53.65.143.25453.65.143.2551,022
10153.65.144.0/2253.65.144.1 to 53.65.147.25453.65.147.2551,022
10253.65.148.0/2253.65.148.1 to 53.65.151.25453.65.151.2551,022
10353.65.152.0/2253.65.152.1 to 53.65.155.25453.65.155.2551,022
10453.65.156.0/2253.65.156.1 to 53.65.159.25453.65.159.2551,022
10553.65.160.0/2253.65.160.1 to 53.65.163.25453.65.163.2551,022
10653.65.164.0/2253.65.164.1 to 53.65.167.25453.65.167.2551,022
10753.65.168.0/2253.65.168.1 to 53.65.171.25453.65.171.2551,022
10853.65.172.0/2253.65.172.1 to 53.65.175.25453.65.175.2551,022
10953.65.176.0/2253.65.176.1 to 53.65.179.25453.65.179.2551,022
11053.65.180.0/2253.65.180.1 to 53.65.183.25453.65.183.2551,022
11153.65.184.0/2253.65.184.1 to 53.65.187.25453.65.187.2551,022
11253.65.188.0/2253.65.188.1 to 53.65.191.25453.65.191.2551,022
11353.65.192.0/2253.65.192.1 to 53.65.195.25453.65.195.2551,022
11453.65.196.0/2253.65.196.1 to 53.65.199.25453.65.199.2551,022
11553.65.200.0/2253.65.200.1 to 53.65.203.25453.65.203.2551,022
11653.65.204.0/2253.65.204.1 to 53.65.207.25453.65.207.2551,022
11753.65.208.0/2253.65.208.1 to 53.65.211.25453.65.211.2551,022
11853.65.212.0/2253.65.212.1 to 53.65.215.25453.65.215.2551,022
11953.65.216.0/2253.65.216.1 to 53.65.219.25453.65.219.2551,022
12053.65.220.0/2253.65.220.1 to 53.65.223.25453.65.223.2551,022
12153.65.224.0/2253.65.224.1 to 53.65.227.25453.65.227.2551,022
12253.65.228.0/2253.65.228.1 to 53.65.231.25453.65.231.2551,022
12353.65.232.0/2253.65.232.1 to 53.65.235.25453.65.235.2551,022
12453.65.236.0/2253.65.236.1 to 53.65.239.25453.65.239.2551,022
12553.65.240.0/2253.65.240.1 to 53.65.243.25453.65.243.2551,022
12653.65.244.0/2253.65.244.1 to 53.65.247.25453.65.247.2551,022
12753.65.248.0/2253.65.248.1 to 53.65.251.25453.65.251.2551,022
12853.65.252.0/2253.65.252.1 to 53.65.255.25453.65.255.2551,022
12953.66.0.0/2253.66.0.1 to 53.66.3.25453.66.3.2551,022
13053.66.4.0/2253.66.4.1 to 53.66.7.25453.66.7.2551,022
13153.66.8.0/2253.66.8.1 to 53.66.11.25453.66.11.2551,022
13253.66.12.0/2253.66.12.1 to 53.66.15.25453.66.15.2551,022
13353.66.16.0/2253.66.16.1 to 53.66.19.25453.66.19.2551,022
13453.66.20.0/2253.66.20.1 to 53.66.23.25453.66.23.2551,022
13553.66.24.0/2253.66.24.1 to 53.66.27.25453.66.27.2551,022
13653.66.28.0/2253.66.28.1 to 53.66.31.25453.66.31.2551,022
13753.66.32.0/2253.66.32.1 to 53.66.35.25453.66.35.2551,022
13853.66.36.0/2253.66.36.1 to 53.66.39.25453.66.39.2551,022
13953.66.40.0/2253.66.40.1 to 53.66.43.25453.66.43.2551,022
14053.66.44.0/2253.66.44.1 to 53.66.47.25453.66.47.2551,022
14153.66.48.0/2253.66.48.1 to 53.66.51.25453.66.51.2551,022
14253.66.52.0/2253.66.52.1 to 53.66.55.25453.66.55.2551,022
14353.66.56.0/2253.66.56.1 to 53.66.59.25453.66.59.2551,022
14453.66.60.0/2253.66.60.1 to 53.66.63.25453.66.63.2551,022
14553.66.64.0/2253.66.64.1 to 53.66.67.25453.66.67.2551,022
14653.66.68.0/2253.66.68.1 to 53.66.71.25453.66.71.2551,022
14753.66.72.0/2253.66.72.1 to 53.66.75.25453.66.75.2551,022
14853.66.76.0/2253.66.76.1 to 53.66.79.25453.66.79.2551,022
14953.66.80.0/2253.66.80.1 to 53.66.83.25453.66.83.2551,022
15053.66.84.0/2253.66.84.1 to 53.66.87.25453.66.87.2551,022
15153.66.88.0/2253.66.88.1 to 53.66.91.25453.66.91.2551,022
15253.66.92.0/2253.66.92.1 to 53.66.95.25453.66.95.2551,022
15353.66.96.0/2253.66.96.1 to 53.66.99.25453.66.99.2551,022
15453.66.100.0/2253.66.100.1 to 53.66.103.25453.66.103.2551,022
15553.66.104.0/2253.66.104.1 to 53.66.107.25453.66.107.2551,022
15653.66.108.0/2253.66.108.1 to 53.66.111.25453.66.111.2551,022
15753.66.112.0/2253.66.112.1 to 53.66.115.25453.66.115.2551,022
15853.66.116.0/2253.66.116.1 to 53.66.119.25453.66.119.2551,022
15953.66.120.0/2253.66.120.1 to 53.66.123.25453.66.123.2551,022
16053.66.124.0/2253.66.124.1 to 53.66.127.25453.66.127.2551,022
16153.66.128.0/2253.66.128.1 to 53.66.131.25453.66.131.2551,022
16253.66.132.0/2253.66.132.1 to 53.66.135.25453.66.135.2551,022
16353.66.136.0/2253.66.136.1 to 53.66.139.25453.66.139.2551,022
16453.66.140.0/2253.66.140.1 to 53.66.143.25453.66.143.2551,022
16553.66.144.0/2253.66.144.1 to 53.66.147.25453.66.147.2551,022
16653.66.148.0/2253.66.148.1 to 53.66.151.25453.66.151.2551,022
16753.66.152.0/2253.66.152.1 to 53.66.155.25453.66.155.2551,022
16853.66.156.0/2253.66.156.1 to 53.66.159.25453.66.159.2551,022
16953.66.160.0/2253.66.160.1 to 53.66.163.25453.66.163.2551,022
17053.66.164.0/2253.66.164.1 to 53.66.167.25453.66.167.2551,022
17153.66.168.0/2253.66.168.1 to 53.66.171.25453.66.171.2551,022
17253.66.172.0/2253.66.172.1 to 53.66.175.25453.66.175.2551,022
17353.66.176.0/2253.66.176.1 to 53.66.179.25453.66.179.2551,022
17453.66.180.0/2253.66.180.1 to 53.66.183.25453.66.183.2551,022
17553.66.184.0/2253.66.184.1 to 53.66.187.25453.66.187.2551,022
17653.66.188.0/2253.66.188.1 to 53.66.191.25453.66.191.2551,022
17753.66.192.0/2253.66.192.1 to 53.66.195.25453.66.195.2551,022
17853.66.196.0/2253.66.196.1 to 53.66.199.25453.66.199.2551,022
17953.66.200.0/2253.66.200.1 to 53.66.203.25453.66.203.2551,022
18053.66.204.0/2253.66.204.1 to 53.66.207.25453.66.207.2551,022
18153.66.208.0/2253.66.208.1 to 53.66.211.25453.66.211.2551,022
18253.66.212.0/2253.66.212.1 to 53.66.215.25453.66.215.2551,022
18353.66.216.0/2253.66.216.1 to 53.66.219.25453.66.219.2551,022
18453.66.220.0/2253.66.220.1 to 53.66.223.25453.66.223.2551,022
18553.66.224.0/2253.66.224.1 to 53.66.227.25453.66.227.2551,022
18653.66.228.0/2253.66.228.1 to 53.66.231.25453.66.231.2551,022
18753.66.232.0/2253.66.232.1 to 53.66.235.25453.66.235.2551,022
18853.66.236.0/2253.66.236.1 to 53.66.239.25453.66.239.2551,022
18953.66.240.0/2253.66.240.1 to 53.66.243.25453.66.243.2551,022
19053.66.244.0/2253.66.244.1 to 53.66.247.25453.66.247.2551,022
19153.66.248.0/2253.66.248.1 to 53.66.251.25453.66.251.2551,022
19253.66.252.0/2253.66.252.1 to 53.66.255.25453.66.255.2551,022
19353.67.0.0/2253.67.0.1 to 53.67.3.25453.67.3.2551,022
19453.67.4.0/2253.67.4.1 to 53.67.7.25453.67.7.2551,022
19553.67.8.0/2253.67.8.1 to 53.67.11.25453.67.11.2551,022
19653.67.12.0/2253.67.12.1 to 53.67.15.25453.67.15.2551,022
19753.67.16.0/2253.67.16.1 to 53.67.19.25453.67.19.2551,022
19853.67.20.0/2253.67.20.1 to 53.67.23.25453.67.23.2551,022
19953.67.24.0/2253.67.24.1 to 53.67.27.25453.67.27.2551,022
20053.67.28.0/2253.67.28.1 to 53.67.31.25453.67.31.2551,022
20153.67.32.0/2253.67.32.1 to 53.67.35.25453.67.35.2551,022
20253.67.36.0/2253.67.36.1 to 53.67.39.25453.67.39.2551,022
20353.67.40.0/2253.67.40.1 to 53.67.43.25453.67.43.2551,022
20453.67.44.0/2253.67.44.1 to 53.67.47.25453.67.47.2551,022
20553.67.48.0/2253.67.48.1 to 53.67.51.25453.67.51.2551,022
20653.67.52.0/2253.67.52.1 to 53.67.55.25453.67.55.2551,022
20753.67.56.0/2253.67.56.1 to 53.67.59.25453.67.59.2551,022
20853.67.60.0/2253.67.60.1 to 53.67.63.25453.67.63.2551,022
20953.67.64.0/2253.67.64.1 to 53.67.67.25453.67.67.2551,022
21053.67.68.0/2253.67.68.1 to 53.67.71.25453.67.71.2551,022
21153.67.72.0/2253.67.72.1 to 53.67.75.25453.67.75.2551,022
21253.67.76.0/2253.67.76.1 to 53.67.79.25453.67.79.2551,022
21353.67.80.0/2253.67.80.1 to 53.67.83.25453.67.83.2551,022
21453.67.84.0/2253.67.84.1 to 53.67.87.25453.67.87.2551,022
21553.67.88.0/2253.67.88.1 to 53.67.91.25453.67.91.2551,022
21653.67.92.0/2253.67.92.1 to 53.67.95.25453.67.95.2551,022
21753.67.96.0/2253.67.96.1 to 53.67.99.25453.67.99.2551,022
21853.67.100.0/2253.67.100.1 to 53.67.103.25453.67.103.2551,022
21953.67.104.0/2253.67.104.1 to 53.67.107.25453.67.107.2551,022
22053.67.108.0/2253.67.108.1 to 53.67.111.25453.67.111.2551,022
22153.67.112.0/2253.67.112.1 to 53.67.115.25453.67.115.2551,022
22253.67.116.0/2253.67.116.1 to 53.67.119.25453.67.119.2551,022
22353.67.120.0/2253.67.120.1 to 53.67.123.25453.67.123.2551,022
22453.67.124.0/2253.67.124.1 to 53.67.127.25453.67.127.2551,022
22553.67.128.0/2253.67.128.1 to 53.67.131.25453.67.131.2551,022
22653.67.132.0/2253.67.132.1 to 53.67.135.25453.67.135.2551,022
22753.67.136.0/2253.67.136.1 to 53.67.139.25453.67.139.2551,022
22853.67.140.0/2253.67.140.1 to 53.67.143.25453.67.143.2551,022
22953.67.144.0/2253.67.144.1 to 53.67.147.25453.67.147.2551,022
23053.67.148.0/2253.67.148.1 to 53.67.151.25453.67.151.2551,022
23153.67.152.0/2253.67.152.1 to 53.67.155.25453.67.155.2551,022
23253.67.156.0/2253.67.156.1 to 53.67.159.25453.67.159.2551,022
23353.67.160.0/2253.67.160.1 to 53.67.163.25453.67.163.2551,022
23453.67.164.0/2253.67.164.1 to 53.67.167.25453.67.167.2551,022
23553.67.168.0/2253.67.168.1 to 53.67.171.25453.67.171.2551,022
23653.67.172.0/2253.67.172.1 to 53.67.175.25453.67.175.2551,022
23753.67.176.0/2253.67.176.1 to 53.67.179.25453.67.179.2551,022
23853.67.180.0/2253.67.180.1 to 53.67.183.25453.67.183.2551,022
23953.67.184.0/2253.67.184.1 to 53.67.187.25453.67.187.2551,022
24053.67.188.0/2253.67.188.1 to 53.67.191.25453.67.191.2551,022
24153.67.192.0/2253.67.192.1 to 53.67.195.25453.67.195.2551,022
24253.67.196.0/2253.67.196.1 to 53.67.199.25453.67.199.2551,022
24353.67.200.0/2253.67.200.1 to 53.67.203.25453.67.203.2551,022
24453.67.204.0/2253.67.204.1 to 53.67.207.25453.67.207.2551,022
24553.67.208.0/2253.67.208.1 to 53.67.211.25453.67.211.2551,022
24653.67.212.0/2253.67.212.1 to 53.67.215.25453.67.215.2551,022
24753.67.216.0/2253.67.216.1 to 53.67.219.25453.67.219.2551,022
24853.67.220.0/2253.67.220.1 to 53.67.223.25453.67.223.2551,022
24953.67.224.0/2253.67.224.1 to 53.67.227.25453.67.227.2551,022
25053.67.228.0/2253.67.228.1 to 53.67.231.25453.67.231.2551,022
25153.67.232.0/2253.67.232.1 to 53.67.235.25453.67.235.2551,022
25253.67.236.0/2253.67.236.1 to 53.67.239.25453.67.239.2551,022
25353.67.240.0/2253.67.240.1 to 53.67.243.25453.67.243.2551,022
25453.67.244.0/2253.67.244.1 to 53.67.247.25453.67.247.2551,022
25553.67.248.0/2253.67.248.1 to 53.67.251.25453.67.251.2551,022
25653.67.252.0/2253.67.252.1 to 53.67.255.25453.67.255.2551,022

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.