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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.

Network53.154.0.0/15
Usable hosts131,070
Subnet mask255.254.0.0
Addresses131,072
Network address
53.154.0.0
Broadcast address
53.155.255.255
First usable
53.154.0.1
Last usable
53.155.255.254
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 359A0000 · Integer 899284992 to 899416063
Reverse DNS zones
154.53.in-addr.arpa
155.53.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
Address00110101.10011010.00000000.0000000053.154.0.0
Subnet mask11111111.11111110.00000000.00000000255.254.0.0
Network00110101.10011010.00000000.0000000053.154.0.0
Broadcast00110101.10011011.11111111.1111111153.155.255.255
Split into smaller subnets/24
/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)

53.154.0.0/15 makes 512 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
153.154.0.0/2453.154.0.1 to 53.154.0.25453.154.0.255254
253.154.1.0/2453.154.1.1 to 53.154.1.25453.154.1.255254
353.154.2.0/2453.154.2.1 to 53.154.2.25453.154.2.255254
453.154.3.0/2453.154.3.1 to 53.154.3.25453.154.3.255254
553.154.4.0/2453.154.4.1 to 53.154.4.25453.154.4.255254
653.154.5.0/2453.154.5.1 to 53.154.5.25453.154.5.255254
753.154.6.0/2453.154.6.1 to 53.154.6.25453.154.6.255254
853.154.7.0/2453.154.7.1 to 53.154.7.25453.154.7.255254
953.154.8.0/2453.154.8.1 to 53.154.8.25453.154.8.255254
1053.154.9.0/2453.154.9.1 to 53.154.9.25453.154.9.255254
1153.154.10.0/2453.154.10.1 to 53.154.10.25453.154.10.255254
1253.154.11.0/2453.154.11.1 to 53.154.11.25453.154.11.255254
1353.154.12.0/2453.154.12.1 to 53.154.12.25453.154.12.255254
1453.154.13.0/2453.154.13.1 to 53.154.13.25453.154.13.255254
1553.154.14.0/2453.154.14.1 to 53.154.14.25453.154.14.255254
1653.154.15.0/2453.154.15.1 to 53.154.15.25453.154.15.255254
1753.154.16.0/2453.154.16.1 to 53.154.16.25453.154.16.255254
1853.154.17.0/2453.154.17.1 to 53.154.17.25453.154.17.255254
1953.154.18.0/2453.154.18.1 to 53.154.18.25453.154.18.255254
2053.154.19.0/2453.154.19.1 to 53.154.19.25453.154.19.255254
2153.154.20.0/2453.154.20.1 to 53.154.20.25453.154.20.255254
2253.154.21.0/2453.154.21.1 to 53.154.21.25453.154.21.255254
2353.154.22.0/2453.154.22.1 to 53.154.22.25453.154.22.255254
2453.154.23.0/2453.154.23.1 to 53.154.23.25453.154.23.255254
2553.154.24.0/2453.154.24.1 to 53.154.24.25453.154.24.255254
2653.154.25.0/2453.154.25.1 to 53.154.25.25453.154.25.255254
2753.154.26.0/2453.154.26.1 to 53.154.26.25453.154.26.255254
2853.154.27.0/2453.154.27.1 to 53.154.27.25453.154.27.255254
2953.154.28.0/2453.154.28.1 to 53.154.28.25453.154.28.255254
3053.154.29.0/2453.154.29.1 to 53.154.29.25453.154.29.255254
3153.154.30.0/2453.154.30.1 to 53.154.30.25453.154.30.255254
3253.154.31.0/2453.154.31.1 to 53.154.31.25453.154.31.255254
3353.154.32.0/2453.154.32.1 to 53.154.32.25453.154.32.255254
3453.154.33.0/2453.154.33.1 to 53.154.33.25453.154.33.255254
3553.154.34.0/2453.154.34.1 to 53.154.34.25453.154.34.255254
3653.154.35.0/2453.154.35.1 to 53.154.35.25453.154.35.255254
3753.154.36.0/2453.154.36.1 to 53.154.36.25453.154.36.255254
3853.154.37.0/2453.154.37.1 to 53.154.37.25453.154.37.255254
3953.154.38.0/2453.154.38.1 to 53.154.38.25453.154.38.255254
4053.154.39.0/2453.154.39.1 to 53.154.39.25453.154.39.255254
4153.154.40.0/2453.154.40.1 to 53.154.40.25453.154.40.255254
4253.154.41.0/2453.154.41.1 to 53.154.41.25453.154.41.255254
4353.154.42.0/2453.154.42.1 to 53.154.42.25453.154.42.255254
4453.154.43.0/2453.154.43.1 to 53.154.43.25453.154.43.255254
4553.154.44.0/2453.154.44.1 to 53.154.44.25453.154.44.255254
4653.154.45.0/2453.154.45.1 to 53.154.45.25453.154.45.255254
4753.154.46.0/2453.154.46.1 to 53.154.46.25453.154.46.255254
4853.154.47.0/2453.154.47.1 to 53.154.47.25453.154.47.255254
4953.154.48.0/2453.154.48.1 to 53.154.48.25453.154.48.255254
5053.154.49.0/2453.154.49.1 to 53.154.49.25453.154.49.255254
5153.154.50.0/2453.154.50.1 to 53.154.50.25453.154.50.255254
5253.154.51.0/2453.154.51.1 to 53.154.51.25453.154.51.255254
5353.154.52.0/2453.154.52.1 to 53.154.52.25453.154.52.255254
5453.154.53.0/2453.154.53.1 to 53.154.53.25453.154.53.255254
5553.154.54.0/2453.154.54.1 to 53.154.54.25453.154.54.255254
5653.154.55.0/2453.154.55.1 to 53.154.55.25453.154.55.255254
5753.154.56.0/2453.154.56.1 to 53.154.56.25453.154.56.255254
5853.154.57.0/2453.154.57.1 to 53.154.57.25453.154.57.255254
5953.154.58.0/2453.154.58.1 to 53.154.58.25453.154.58.255254
6053.154.59.0/2453.154.59.1 to 53.154.59.25453.154.59.255254
6153.154.60.0/2453.154.60.1 to 53.154.60.25453.154.60.255254
6253.154.61.0/2453.154.61.1 to 53.154.61.25453.154.61.255254
6353.154.62.0/2453.154.62.1 to 53.154.62.25453.154.62.255254
6453.154.63.0/2453.154.63.1 to 53.154.63.25453.154.63.255254
6553.154.64.0/2453.154.64.1 to 53.154.64.25453.154.64.255254
6653.154.65.0/2453.154.65.1 to 53.154.65.25453.154.65.255254
6753.154.66.0/2453.154.66.1 to 53.154.66.25453.154.66.255254
6853.154.67.0/2453.154.67.1 to 53.154.67.25453.154.67.255254
6953.154.68.0/2453.154.68.1 to 53.154.68.25453.154.68.255254
7053.154.69.0/2453.154.69.1 to 53.154.69.25453.154.69.255254
7153.154.70.0/2453.154.70.1 to 53.154.70.25453.154.70.255254
7253.154.71.0/2453.154.71.1 to 53.154.71.25453.154.71.255254
7353.154.72.0/2453.154.72.1 to 53.154.72.25453.154.72.255254
7453.154.73.0/2453.154.73.1 to 53.154.73.25453.154.73.255254
7553.154.74.0/2453.154.74.1 to 53.154.74.25453.154.74.255254
7653.154.75.0/2453.154.75.1 to 53.154.75.25453.154.75.255254
7753.154.76.0/2453.154.76.1 to 53.154.76.25453.154.76.255254
7853.154.77.0/2453.154.77.1 to 53.154.77.25453.154.77.255254
7953.154.78.0/2453.154.78.1 to 53.154.78.25453.154.78.255254
8053.154.79.0/2453.154.79.1 to 53.154.79.25453.154.79.255254
8153.154.80.0/2453.154.80.1 to 53.154.80.25453.154.80.255254
8253.154.81.0/2453.154.81.1 to 53.154.81.25453.154.81.255254
8353.154.82.0/2453.154.82.1 to 53.154.82.25453.154.82.255254
8453.154.83.0/2453.154.83.1 to 53.154.83.25453.154.83.255254
8553.154.84.0/2453.154.84.1 to 53.154.84.25453.154.84.255254
8653.154.85.0/2453.154.85.1 to 53.154.85.25453.154.85.255254
8753.154.86.0/2453.154.86.1 to 53.154.86.25453.154.86.255254
8853.154.87.0/2453.154.87.1 to 53.154.87.25453.154.87.255254
8953.154.88.0/2453.154.88.1 to 53.154.88.25453.154.88.255254
9053.154.89.0/2453.154.89.1 to 53.154.89.25453.154.89.255254
9153.154.90.0/2453.154.90.1 to 53.154.90.25453.154.90.255254
9253.154.91.0/2453.154.91.1 to 53.154.91.25453.154.91.255254
9353.154.92.0/2453.154.92.1 to 53.154.92.25453.154.92.255254
9453.154.93.0/2453.154.93.1 to 53.154.93.25453.154.93.255254
9553.154.94.0/2453.154.94.1 to 53.154.94.25453.154.94.255254
9653.154.95.0/2453.154.95.1 to 53.154.95.25453.154.95.255254
9753.154.96.0/2453.154.96.1 to 53.154.96.25453.154.96.255254
9853.154.97.0/2453.154.97.1 to 53.154.97.25453.154.97.255254
9953.154.98.0/2453.154.98.1 to 53.154.98.25453.154.98.255254
10053.154.99.0/2453.154.99.1 to 53.154.99.25453.154.99.255254
10153.154.100.0/2453.154.100.1 to 53.154.100.25453.154.100.255254
10253.154.101.0/2453.154.101.1 to 53.154.101.25453.154.101.255254
10353.154.102.0/2453.154.102.1 to 53.154.102.25453.154.102.255254
10453.154.103.0/2453.154.103.1 to 53.154.103.25453.154.103.255254
10553.154.104.0/2453.154.104.1 to 53.154.104.25453.154.104.255254
10653.154.105.0/2453.154.105.1 to 53.154.105.25453.154.105.255254
10753.154.106.0/2453.154.106.1 to 53.154.106.25453.154.106.255254
10853.154.107.0/2453.154.107.1 to 53.154.107.25453.154.107.255254
10953.154.108.0/2453.154.108.1 to 53.154.108.25453.154.108.255254
11053.154.109.0/2453.154.109.1 to 53.154.109.25453.154.109.255254
11153.154.110.0/2453.154.110.1 to 53.154.110.25453.154.110.255254
11253.154.111.0/2453.154.111.1 to 53.154.111.25453.154.111.255254
11353.154.112.0/2453.154.112.1 to 53.154.112.25453.154.112.255254
11453.154.113.0/2453.154.113.1 to 53.154.113.25453.154.113.255254
11553.154.114.0/2453.154.114.1 to 53.154.114.25453.154.114.255254
11653.154.115.0/2453.154.115.1 to 53.154.115.25453.154.115.255254
11753.154.116.0/2453.154.116.1 to 53.154.116.25453.154.116.255254
11853.154.117.0/2453.154.117.1 to 53.154.117.25453.154.117.255254
11953.154.118.0/2453.154.118.1 to 53.154.118.25453.154.118.255254
12053.154.119.0/2453.154.119.1 to 53.154.119.25453.154.119.255254
12153.154.120.0/2453.154.120.1 to 53.154.120.25453.154.120.255254
12253.154.121.0/2453.154.121.1 to 53.154.121.25453.154.121.255254
12353.154.122.0/2453.154.122.1 to 53.154.122.25453.154.122.255254
12453.154.123.0/2453.154.123.1 to 53.154.123.25453.154.123.255254
12553.154.124.0/2453.154.124.1 to 53.154.124.25453.154.124.255254
12653.154.125.0/2453.154.125.1 to 53.154.125.25453.154.125.255254
12753.154.126.0/2453.154.126.1 to 53.154.126.25453.154.126.255254
12853.154.127.0/2453.154.127.1 to 53.154.127.25453.154.127.255254
12953.154.128.0/2453.154.128.1 to 53.154.128.25453.154.128.255254
13053.154.129.0/2453.154.129.1 to 53.154.129.25453.154.129.255254
13153.154.130.0/2453.154.130.1 to 53.154.130.25453.154.130.255254
13253.154.131.0/2453.154.131.1 to 53.154.131.25453.154.131.255254
13353.154.132.0/2453.154.132.1 to 53.154.132.25453.154.132.255254
13453.154.133.0/2453.154.133.1 to 53.154.133.25453.154.133.255254
13553.154.134.0/2453.154.134.1 to 53.154.134.25453.154.134.255254
13653.154.135.0/2453.154.135.1 to 53.154.135.25453.154.135.255254
13753.154.136.0/2453.154.136.1 to 53.154.136.25453.154.136.255254
13853.154.137.0/2453.154.137.1 to 53.154.137.25453.154.137.255254
13953.154.138.0/2453.154.138.1 to 53.154.138.25453.154.138.255254
14053.154.139.0/2453.154.139.1 to 53.154.139.25453.154.139.255254
14153.154.140.0/2453.154.140.1 to 53.154.140.25453.154.140.255254
14253.154.141.0/2453.154.141.1 to 53.154.141.25453.154.141.255254
14353.154.142.0/2453.154.142.1 to 53.154.142.25453.154.142.255254
14453.154.143.0/2453.154.143.1 to 53.154.143.25453.154.143.255254
14553.154.144.0/2453.154.144.1 to 53.154.144.25453.154.144.255254
14653.154.145.0/2453.154.145.1 to 53.154.145.25453.154.145.255254
14753.154.146.0/2453.154.146.1 to 53.154.146.25453.154.146.255254
14853.154.147.0/2453.154.147.1 to 53.154.147.25453.154.147.255254
14953.154.148.0/2453.154.148.1 to 53.154.148.25453.154.148.255254
15053.154.149.0/2453.154.149.1 to 53.154.149.25453.154.149.255254
15153.154.150.0/2453.154.150.1 to 53.154.150.25453.154.150.255254
15253.154.151.0/2453.154.151.1 to 53.154.151.25453.154.151.255254
15353.154.152.0/2453.154.152.1 to 53.154.152.25453.154.152.255254
15453.154.153.0/2453.154.153.1 to 53.154.153.25453.154.153.255254
15553.154.154.0/2453.154.154.1 to 53.154.154.25453.154.154.255254
15653.154.155.0/2453.154.155.1 to 53.154.155.25453.154.155.255254
15753.154.156.0/2453.154.156.1 to 53.154.156.25453.154.156.255254
15853.154.157.0/2453.154.157.1 to 53.154.157.25453.154.157.255254
15953.154.158.0/2453.154.158.1 to 53.154.158.25453.154.158.255254
16053.154.159.0/2453.154.159.1 to 53.154.159.25453.154.159.255254
16153.154.160.0/2453.154.160.1 to 53.154.160.25453.154.160.255254
16253.154.161.0/2453.154.161.1 to 53.154.161.25453.154.161.255254
16353.154.162.0/2453.154.162.1 to 53.154.162.25453.154.162.255254
16453.154.163.0/2453.154.163.1 to 53.154.163.25453.154.163.255254
16553.154.164.0/2453.154.164.1 to 53.154.164.25453.154.164.255254
16653.154.165.0/2453.154.165.1 to 53.154.165.25453.154.165.255254
16753.154.166.0/2453.154.166.1 to 53.154.166.25453.154.166.255254
16853.154.167.0/2453.154.167.1 to 53.154.167.25453.154.167.255254
16953.154.168.0/2453.154.168.1 to 53.154.168.25453.154.168.255254
17053.154.169.0/2453.154.169.1 to 53.154.169.25453.154.169.255254
17153.154.170.0/2453.154.170.1 to 53.154.170.25453.154.170.255254
17253.154.171.0/2453.154.171.1 to 53.154.171.25453.154.171.255254
17353.154.172.0/2453.154.172.1 to 53.154.172.25453.154.172.255254
17453.154.173.0/2453.154.173.1 to 53.154.173.25453.154.173.255254
17553.154.174.0/2453.154.174.1 to 53.154.174.25453.154.174.255254
17653.154.175.0/2453.154.175.1 to 53.154.175.25453.154.175.255254
17753.154.176.0/2453.154.176.1 to 53.154.176.25453.154.176.255254
17853.154.177.0/2453.154.177.1 to 53.154.177.25453.154.177.255254
17953.154.178.0/2453.154.178.1 to 53.154.178.25453.154.178.255254
18053.154.179.0/2453.154.179.1 to 53.154.179.25453.154.179.255254
18153.154.180.0/2453.154.180.1 to 53.154.180.25453.154.180.255254
18253.154.181.0/2453.154.181.1 to 53.154.181.25453.154.181.255254
18353.154.182.0/2453.154.182.1 to 53.154.182.25453.154.182.255254
18453.154.183.0/2453.154.183.1 to 53.154.183.25453.154.183.255254
18553.154.184.0/2453.154.184.1 to 53.154.184.25453.154.184.255254
18653.154.185.0/2453.154.185.1 to 53.154.185.25453.154.185.255254
18753.154.186.0/2453.154.186.1 to 53.154.186.25453.154.186.255254
18853.154.187.0/2453.154.187.1 to 53.154.187.25453.154.187.255254
18953.154.188.0/2453.154.188.1 to 53.154.188.25453.154.188.255254
19053.154.189.0/2453.154.189.1 to 53.154.189.25453.154.189.255254
19153.154.190.0/2453.154.190.1 to 53.154.190.25453.154.190.255254
19253.154.191.0/2453.154.191.1 to 53.154.191.25453.154.191.255254
19353.154.192.0/2453.154.192.1 to 53.154.192.25453.154.192.255254
19453.154.193.0/2453.154.193.1 to 53.154.193.25453.154.193.255254
19553.154.194.0/2453.154.194.1 to 53.154.194.25453.154.194.255254
19653.154.195.0/2453.154.195.1 to 53.154.195.25453.154.195.255254
19753.154.196.0/2453.154.196.1 to 53.154.196.25453.154.196.255254
19853.154.197.0/2453.154.197.1 to 53.154.197.25453.154.197.255254
19953.154.198.0/2453.154.198.1 to 53.154.198.25453.154.198.255254
20053.154.199.0/2453.154.199.1 to 53.154.199.25453.154.199.255254
20153.154.200.0/2453.154.200.1 to 53.154.200.25453.154.200.255254
20253.154.201.0/2453.154.201.1 to 53.154.201.25453.154.201.255254
20353.154.202.0/2453.154.202.1 to 53.154.202.25453.154.202.255254
20453.154.203.0/2453.154.203.1 to 53.154.203.25453.154.203.255254
20553.154.204.0/2453.154.204.1 to 53.154.204.25453.154.204.255254
20653.154.205.0/2453.154.205.1 to 53.154.205.25453.154.205.255254
20753.154.206.0/2453.154.206.1 to 53.154.206.25453.154.206.255254
20853.154.207.0/2453.154.207.1 to 53.154.207.25453.154.207.255254
20953.154.208.0/2453.154.208.1 to 53.154.208.25453.154.208.255254
21053.154.209.0/2453.154.209.1 to 53.154.209.25453.154.209.255254
21153.154.210.0/2453.154.210.1 to 53.154.210.25453.154.210.255254
21253.154.211.0/2453.154.211.1 to 53.154.211.25453.154.211.255254
21353.154.212.0/2453.154.212.1 to 53.154.212.25453.154.212.255254
21453.154.213.0/2453.154.213.1 to 53.154.213.25453.154.213.255254
21553.154.214.0/2453.154.214.1 to 53.154.214.25453.154.214.255254
21653.154.215.0/2453.154.215.1 to 53.154.215.25453.154.215.255254
21753.154.216.0/2453.154.216.1 to 53.154.216.25453.154.216.255254
21853.154.217.0/2453.154.217.1 to 53.154.217.25453.154.217.255254
21953.154.218.0/2453.154.218.1 to 53.154.218.25453.154.218.255254
22053.154.219.0/2453.154.219.1 to 53.154.219.25453.154.219.255254
22153.154.220.0/2453.154.220.1 to 53.154.220.25453.154.220.255254
22253.154.221.0/2453.154.221.1 to 53.154.221.25453.154.221.255254
22353.154.222.0/2453.154.222.1 to 53.154.222.25453.154.222.255254
22453.154.223.0/2453.154.223.1 to 53.154.223.25453.154.223.255254
22553.154.224.0/2453.154.224.1 to 53.154.224.25453.154.224.255254
22653.154.225.0/2453.154.225.1 to 53.154.225.25453.154.225.255254
22753.154.226.0/2453.154.226.1 to 53.154.226.25453.154.226.255254
22853.154.227.0/2453.154.227.1 to 53.154.227.25453.154.227.255254
22953.154.228.0/2453.154.228.1 to 53.154.228.25453.154.228.255254
23053.154.229.0/2453.154.229.1 to 53.154.229.25453.154.229.255254
23153.154.230.0/2453.154.230.1 to 53.154.230.25453.154.230.255254
23253.154.231.0/2453.154.231.1 to 53.154.231.25453.154.231.255254
23353.154.232.0/2453.154.232.1 to 53.154.232.25453.154.232.255254
23453.154.233.0/2453.154.233.1 to 53.154.233.25453.154.233.255254
23553.154.234.0/2453.154.234.1 to 53.154.234.25453.154.234.255254
23653.154.235.0/2453.154.235.1 to 53.154.235.25453.154.235.255254
23753.154.236.0/2453.154.236.1 to 53.154.236.25453.154.236.255254
23853.154.237.0/2453.154.237.1 to 53.154.237.25453.154.237.255254
23953.154.238.0/2453.154.238.1 to 53.154.238.25453.154.238.255254
24053.154.239.0/2453.154.239.1 to 53.154.239.25453.154.239.255254
24153.154.240.0/2453.154.240.1 to 53.154.240.25453.154.240.255254
24253.154.241.0/2453.154.241.1 to 53.154.241.25453.154.241.255254
24353.154.242.0/2453.154.242.1 to 53.154.242.25453.154.242.255254
24453.154.243.0/2453.154.243.1 to 53.154.243.25453.154.243.255254
24553.154.244.0/2453.154.244.1 to 53.154.244.25453.154.244.255254
24653.154.245.0/2453.154.245.1 to 53.154.245.25453.154.245.255254
24753.154.246.0/2453.154.246.1 to 53.154.246.25453.154.246.255254
24853.154.247.0/2453.154.247.1 to 53.154.247.25453.154.247.255254
24953.154.248.0/2453.154.248.1 to 53.154.248.25453.154.248.255254
25053.154.249.0/2453.154.249.1 to 53.154.249.25453.154.249.255254
25153.154.250.0/2453.154.250.1 to 53.154.250.25453.154.250.255254
25253.154.251.0/2453.154.251.1 to 53.154.251.25453.154.251.255254
25353.154.252.0/2453.154.252.1 to 53.154.252.25453.154.252.255254
25453.154.253.0/2453.154.253.1 to 53.154.253.25453.154.253.255254
25553.154.254.0/2453.154.254.1 to 53.154.254.25453.154.254.255254
25653.154.255.0/2453.154.255.1 to 53.154.255.25453.154.255.255254

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.