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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.

Network98.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
98.0.0.0
Broadcast address
99.255.255.255
First usable
98.0.0.1
Last usable
99.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
A (default /8)
As numbers
Hex 62000000 · Integer 1644167168 to 1677721599
Reverse DNS zones
98.in-addr.arpa
99.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01100010.00000000.00000000.0000000098.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network01100010.00000000.00000000.0000000098.0.0.0
Broadcast01100011.11111111.11111111.1111111199.255.255.255
Split into smaller subnets/15
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

98.0.0.0/7 makes 256 subnets of /15.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
198.0.0.0/1598.0.0.1 to 98.1.255.25498.1.255.255131,070
298.2.0.0/1598.2.0.1 to 98.3.255.25498.3.255.255131,070
398.4.0.0/1598.4.0.1 to 98.5.255.25498.5.255.255131,070
498.6.0.0/1598.6.0.1 to 98.7.255.25498.7.255.255131,070
598.8.0.0/1598.8.0.1 to 98.9.255.25498.9.255.255131,070
698.10.0.0/1598.10.0.1 to 98.11.255.25498.11.255.255131,070
798.12.0.0/1598.12.0.1 to 98.13.255.25498.13.255.255131,070
898.14.0.0/1598.14.0.1 to 98.15.255.25498.15.255.255131,070
998.16.0.0/1598.16.0.1 to 98.17.255.25498.17.255.255131,070
1098.18.0.0/1598.18.0.1 to 98.19.255.25498.19.255.255131,070
1198.20.0.0/1598.20.0.1 to 98.21.255.25498.21.255.255131,070
1298.22.0.0/1598.22.0.1 to 98.23.255.25498.23.255.255131,070
1398.24.0.0/1598.24.0.1 to 98.25.255.25498.25.255.255131,070
1498.26.0.0/1598.26.0.1 to 98.27.255.25498.27.255.255131,070
1598.28.0.0/1598.28.0.1 to 98.29.255.25498.29.255.255131,070
1698.30.0.0/1598.30.0.1 to 98.31.255.25498.31.255.255131,070
1798.32.0.0/1598.32.0.1 to 98.33.255.25498.33.255.255131,070
1898.34.0.0/1598.34.0.1 to 98.35.255.25498.35.255.255131,070
1998.36.0.0/1598.36.0.1 to 98.37.255.25498.37.255.255131,070
2098.38.0.0/1598.38.0.1 to 98.39.255.25498.39.255.255131,070
2198.40.0.0/1598.40.0.1 to 98.41.255.25498.41.255.255131,070
2298.42.0.0/1598.42.0.1 to 98.43.255.25498.43.255.255131,070
2398.44.0.0/1598.44.0.1 to 98.45.255.25498.45.255.255131,070
2498.46.0.0/1598.46.0.1 to 98.47.255.25498.47.255.255131,070
2598.48.0.0/1598.48.0.1 to 98.49.255.25498.49.255.255131,070
2698.50.0.0/1598.50.0.1 to 98.51.255.25498.51.255.255131,070
2798.52.0.0/1598.52.0.1 to 98.53.255.25498.53.255.255131,070
2898.54.0.0/1598.54.0.1 to 98.55.255.25498.55.255.255131,070
2998.56.0.0/1598.56.0.1 to 98.57.255.25498.57.255.255131,070
3098.58.0.0/1598.58.0.1 to 98.59.255.25498.59.255.255131,070
3198.60.0.0/1598.60.0.1 to 98.61.255.25498.61.255.255131,070
3298.62.0.0/1598.62.0.1 to 98.63.255.25498.63.255.255131,070
3398.64.0.0/1598.64.0.1 to 98.65.255.25498.65.255.255131,070
3498.66.0.0/1598.66.0.1 to 98.67.255.25498.67.255.255131,070
3598.68.0.0/1598.68.0.1 to 98.69.255.25498.69.255.255131,070
3698.70.0.0/1598.70.0.1 to 98.71.255.25498.71.255.255131,070
3798.72.0.0/1598.72.0.1 to 98.73.255.25498.73.255.255131,070
3898.74.0.0/1598.74.0.1 to 98.75.255.25498.75.255.255131,070
3998.76.0.0/1598.76.0.1 to 98.77.255.25498.77.255.255131,070
4098.78.0.0/1598.78.0.1 to 98.79.255.25498.79.255.255131,070
4198.80.0.0/1598.80.0.1 to 98.81.255.25498.81.255.255131,070
4298.82.0.0/1598.82.0.1 to 98.83.255.25498.83.255.255131,070
4398.84.0.0/1598.84.0.1 to 98.85.255.25498.85.255.255131,070
4498.86.0.0/1598.86.0.1 to 98.87.255.25498.87.255.255131,070
4598.88.0.0/1598.88.0.1 to 98.89.255.25498.89.255.255131,070
4698.90.0.0/1598.90.0.1 to 98.91.255.25498.91.255.255131,070
4798.92.0.0/1598.92.0.1 to 98.93.255.25498.93.255.255131,070
4898.94.0.0/1598.94.0.1 to 98.95.255.25498.95.255.255131,070
4998.96.0.0/1598.96.0.1 to 98.97.255.25498.97.255.255131,070
5098.98.0.0/1598.98.0.1 to 98.99.255.25498.99.255.255131,070
5198.100.0.0/1598.100.0.1 to 98.101.255.25498.101.255.255131,070
5298.102.0.0/1598.102.0.1 to 98.103.255.25498.103.255.255131,070
5398.104.0.0/1598.104.0.1 to 98.105.255.25498.105.255.255131,070
5498.106.0.0/1598.106.0.1 to 98.107.255.25498.107.255.255131,070
5598.108.0.0/1598.108.0.1 to 98.109.255.25498.109.255.255131,070
5698.110.0.0/1598.110.0.1 to 98.111.255.25498.111.255.255131,070
5798.112.0.0/1598.112.0.1 to 98.113.255.25498.113.255.255131,070
5898.114.0.0/1598.114.0.1 to 98.115.255.25498.115.255.255131,070
5998.116.0.0/1598.116.0.1 to 98.117.255.25498.117.255.255131,070
6098.118.0.0/1598.118.0.1 to 98.119.255.25498.119.255.255131,070
6198.120.0.0/1598.120.0.1 to 98.121.255.25498.121.255.255131,070
6298.122.0.0/1598.122.0.1 to 98.123.255.25498.123.255.255131,070
6398.124.0.0/1598.124.0.1 to 98.125.255.25498.125.255.255131,070
6498.126.0.0/1598.126.0.1 to 98.127.255.25498.127.255.255131,070
6598.128.0.0/1598.128.0.1 to 98.129.255.25498.129.255.255131,070
6698.130.0.0/1598.130.0.1 to 98.131.255.25498.131.255.255131,070
6798.132.0.0/1598.132.0.1 to 98.133.255.25498.133.255.255131,070
6898.134.0.0/1598.134.0.1 to 98.135.255.25498.135.255.255131,070
6998.136.0.0/1598.136.0.1 to 98.137.255.25498.137.255.255131,070
7098.138.0.0/1598.138.0.1 to 98.139.255.25498.139.255.255131,070
7198.140.0.0/1598.140.0.1 to 98.141.255.25498.141.255.255131,070
7298.142.0.0/1598.142.0.1 to 98.143.255.25498.143.255.255131,070
7398.144.0.0/1598.144.0.1 to 98.145.255.25498.145.255.255131,070
7498.146.0.0/1598.146.0.1 to 98.147.255.25498.147.255.255131,070
7598.148.0.0/1598.148.0.1 to 98.149.255.25498.149.255.255131,070
7698.150.0.0/1598.150.0.1 to 98.151.255.25498.151.255.255131,070
7798.152.0.0/1598.152.0.1 to 98.153.255.25498.153.255.255131,070
7898.154.0.0/1598.154.0.1 to 98.155.255.25498.155.255.255131,070
7998.156.0.0/1598.156.0.1 to 98.157.255.25498.157.255.255131,070
8098.158.0.0/1598.158.0.1 to 98.159.255.25498.159.255.255131,070
8198.160.0.0/1598.160.0.1 to 98.161.255.25498.161.255.255131,070
8298.162.0.0/1598.162.0.1 to 98.163.255.25498.163.255.255131,070
8398.164.0.0/1598.164.0.1 to 98.165.255.25498.165.255.255131,070
8498.166.0.0/1598.166.0.1 to 98.167.255.25498.167.255.255131,070
8598.168.0.0/1598.168.0.1 to 98.169.255.25498.169.255.255131,070
8698.170.0.0/1598.170.0.1 to 98.171.255.25498.171.255.255131,070
8798.172.0.0/1598.172.0.1 to 98.173.255.25498.173.255.255131,070
8898.174.0.0/1598.174.0.1 to 98.175.255.25498.175.255.255131,070
8998.176.0.0/1598.176.0.1 to 98.177.255.25498.177.255.255131,070
9098.178.0.0/1598.178.0.1 to 98.179.255.25498.179.255.255131,070
9198.180.0.0/1598.180.0.1 to 98.181.255.25498.181.255.255131,070
9298.182.0.0/1598.182.0.1 to 98.183.255.25498.183.255.255131,070
9398.184.0.0/1598.184.0.1 to 98.185.255.25498.185.255.255131,070
9498.186.0.0/1598.186.0.1 to 98.187.255.25498.187.255.255131,070
9598.188.0.0/1598.188.0.1 to 98.189.255.25498.189.255.255131,070
9698.190.0.0/1598.190.0.1 to 98.191.255.25498.191.255.255131,070
9798.192.0.0/1598.192.0.1 to 98.193.255.25498.193.255.255131,070
9898.194.0.0/1598.194.0.1 to 98.195.255.25498.195.255.255131,070
9998.196.0.0/1598.196.0.1 to 98.197.255.25498.197.255.255131,070
10098.198.0.0/1598.198.0.1 to 98.199.255.25498.199.255.255131,070
10198.200.0.0/1598.200.0.1 to 98.201.255.25498.201.255.255131,070
10298.202.0.0/1598.202.0.1 to 98.203.255.25498.203.255.255131,070
10398.204.0.0/1598.204.0.1 to 98.205.255.25498.205.255.255131,070
10498.206.0.0/1598.206.0.1 to 98.207.255.25498.207.255.255131,070
10598.208.0.0/1598.208.0.1 to 98.209.255.25498.209.255.255131,070
10698.210.0.0/1598.210.0.1 to 98.211.255.25498.211.255.255131,070
10798.212.0.0/1598.212.0.1 to 98.213.255.25498.213.255.255131,070
10898.214.0.0/1598.214.0.1 to 98.215.255.25498.215.255.255131,070
10998.216.0.0/1598.216.0.1 to 98.217.255.25498.217.255.255131,070
11098.218.0.0/1598.218.0.1 to 98.219.255.25498.219.255.255131,070
11198.220.0.0/1598.220.0.1 to 98.221.255.25498.221.255.255131,070
11298.222.0.0/1598.222.0.1 to 98.223.255.25498.223.255.255131,070
11398.224.0.0/1598.224.0.1 to 98.225.255.25498.225.255.255131,070
11498.226.0.0/1598.226.0.1 to 98.227.255.25498.227.255.255131,070
11598.228.0.0/1598.228.0.1 to 98.229.255.25498.229.255.255131,070
11698.230.0.0/1598.230.0.1 to 98.231.255.25498.231.255.255131,070
11798.232.0.0/1598.232.0.1 to 98.233.255.25498.233.255.255131,070
11898.234.0.0/1598.234.0.1 to 98.235.255.25498.235.255.255131,070
11998.236.0.0/1598.236.0.1 to 98.237.255.25498.237.255.255131,070
12098.238.0.0/1598.238.0.1 to 98.239.255.25498.239.255.255131,070
12198.240.0.0/1598.240.0.1 to 98.241.255.25498.241.255.255131,070
12298.242.0.0/1598.242.0.1 to 98.243.255.25498.243.255.255131,070
12398.244.0.0/1598.244.0.1 to 98.245.255.25498.245.255.255131,070
12498.246.0.0/1598.246.0.1 to 98.247.255.25498.247.255.255131,070
12598.248.0.0/1598.248.0.1 to 98.249.255.25498.249.255.255131,070
12698.250.0.0/1598.250.0.1 to 98.251.255.25498.251.255.255131,070
12798.252.0.0/1598.252.0.1 to 98.253.255.25498.253.255.255131,070
12898.254.0.0/1598.254.0.1 to 98.255.255.25498.255.255.255131,070
12999.0.0.0/1599.0.0.1 to 99.1.255.25499.1.255.255131,070
13099.2.0.0/1599.2.0.1 to 99.3.255.25499.3.255.255131,070
13199.4.0.0/1599.4.0.1 to 99.5.255.25499.5.255.255131,070
13299.6.0.0/1599.6.0.1 to 99.7.255.25499.7.255.255131,070
13399.8.0.0/1599.8.0.1 to 99.9.255.25499.9.255.255131,070
13499.10.0.0/1599.10.0.1 to 99.11.255.25499.11.255.255131,070
13599.12.0.0/1599.12.0.1 to 99.13.255.25499.13.255.255131,070
13699.14.0.0/1599.14.0.1 to 99.15.255.25499.15.255.255131,070
13799.16.0.0/1599.16.0.1 to 99.17.255.25499.17.255.255131,070
13899.18.0.0/1599.18.0.1 to 99.19.255.25499.19.255.255131,070
13999.20.0.0/1599.20.0.1 to 99.21.255.25499.21.255.255131,070
14099.22.0.0/1599.22.0.1 to 99.23.255.25499.23.255.255131,070
14199.24.0.0/1599.24.0.1 to 99.25.255.25499.25.255.255131,070
14299.26.0.0/1599.26.0.1 to 99.27.255.25499.27.255.255131,070
14399.28.0.0/1599.28.0.1 to 99.29.255.25499.29.255.255131,070
14499.30.0.0/1599.30.0.1 to 99.31.255.25499.31.255.255131,070
14599.32.0.0/1599.32.0.1 to 99.33.255.25499.33.255.255131,070
14699.34.0.0/1599.34.0.1 to 99.35.255.25499.35.255.255131,070
14799.36.0.0/1599.36.0.1 to 99.37.255.25499.37.255.255131,070
14899.38.0.0/1599.38.0.1 to 99.39.255.25499.39.255.255131,070
14999.40.0.0/1599.40.0.1 to 99.41.255.25499.41.255.255131,070
15099.42.0.0/1599.42.0.1 to 99.43.255.25499.43.255.255131,070
15199.44.0.0/1599.44.0.1 to 99.45.255.25499.45.255.255131,070
15299.46.0.0/1599.46.0.1 to 99.47.255.25499.47.255.255131,070
15399.48.0.0/1599.48.0.1 to 99.49.255.25499.49.255.255131,070
15499.50.0.0/1599.50.0.1 to 99.51.255.25499.51.255.255131,070
15599.52.0.0/1599.52.0.1 to 99.53.255.25499.53.255.255131,070
15699.54.0.0/1599.54.0.1 to 99.55.255.25499.55.255.255131,070
15799.56.0.0/1599.56.0.1 to 99.57.255.25499.57.255.255131,070
15899.58.0.0/1599.58.0.1 to 99.59.255.25499.59.255.255131,070
15999.60.0.0/1599.60.0.1 to 99.61.255.25499.61.255.255131,070
16099.62.0.0/1599.62.0.1 to 99.63.255.25499.63.255.255131,070
16199.64.0.0/1599.64.0.1 to 99.65.255.25499.65.255.255131,070
16299.66.0.0/1599.66.0.1 to 99.67.255.25499.67.255.255131,070
16399.68.0.0/1599.68.0.1 to 99.69.255.25499.69.255.255131,070
16499.70.0.0/1599.70.0.1 to 99.71.255.25499.71.255.255131,070
16599.72.0.0/1599.72.0.1 to 99.73.255.25499.73.255.255131,070
16699.74.0.0/1599.74.0.1 to 99.75.255.25499.75.255.255131,070
16799.76.0.0/1599.76.0.1 to 99.77.255.25499.77.255.255131,070
16899.78.0.0/1599.78.0.1 to 99.79.255.25499.79.255.255131,070
16999.80.0.0/1599.80.0.1 to 99.81.255.25499.81.255.255131,070
17099.82.0.0/1599.82.0.1 to 99.83.255.25499.83.255.255131,070
17199.84.0.0/1599.84.0.1 to 99.85.255.25499.85.255.255131,070
17299.86.0.0/1599.86.0.1 to 99.87.255.25499.87.255.255131,070
17399.88.0.0/1599.88.0.1 to 99.89.255.25499.89.255.255131,070
17499.90.0.0/1599.90.0.1 to 99.91.255.25499.91.255.255131,070
17599.92.0.0/1599.92.0.1 to 99.93.255.25499.93.255.255131,070
17699.94.0.0/1599.94.0.1 to 99.95.255.25499.95.255.255131,070
17799.96.0.0/1599.96.0.1 to 99.97.255.25499.97.255.255131,070
17899.98.0.0/1599.98.0.1 to 99.99.255.25499.99.255.255131,070
17999.100.0.0/1599.100.0.1 to 99.101.255.25499.101.255.255131,070
18099.102.0.0/1599.102.0.1 to 99.103.255.25499.103.255.255131,070
18199.104.0.0/1599.104.0.1 to 99.105.255.25499.105.255.255131,070
18299.106.0.0/1599.106.0.1 to 99.107.255.25499.107.255.255131,070
18399.108.0.0/1599.108.0.1 to 99.109.255.25499.109.255.255131,070
18499.110.0.0/1599.110.0.1 to 99.111.255.25499.111.255.255131,070
18599.112.0.0/1599.112.0.1 to 99.113.255.25499.113.255.255131,070
18699.114.0.0/1599.114.0.1 to 99.115.255.25499.115.255.255131,070
18799.116.0.0/1599.116.0.1 to 99.117.255.25499.117.255.255131,070
18899.118.0.0/1599.118.0.1 to 99.119.255.25499.119.255.255131,070
18999.120.0.0/1599.120.0.1 to 99.121.255.25499.121.255.255131,070
19099.122.0.0/1599.122.0.1 to 99.123.255.25499.123.255.255131,070
19199.124.0.0/1599.124.0.1 to 99.125.255.25499.125.255.255131,070
19299.126.0.0/1599.126.0.1 to 99.127.255.25499.127.255.255131,070
19399.128.0.0/1599.128.0.1 to 99.129.255.25499.129.255.255131,070
19499.130.0.0/1599.130.0.1 to 99.131.255.25499.131.255.255131,070
19599.132.0.0/1599.132.0.1 to 99.133.255.25499.133.255.255131,070
19699.134.0.0/1599.134.0.1 to 99.135.255.25499.135.255.255131,070
19799.136.0.0/1599.136.0.1 to 99.137.255.25499.137.255.255131,070
19899.138.0.0/1599.138.0.1 to 99.139.255.25499.139.255.255131,070
19999.140.0.0/1599.140.0.1 to 99.141.255.25499.141.255.255131,070
20099.142.0.0/1599.142.0.1 to 99.143.255.25499.143.255.255131,070
20199.144.0.0/1599.144.0.1 to 99.145.255.25499.145.255.255131,070
20299.146.0.0/1599.146.0.1 to 99.147.255.25499.147.255.255131,070
20399.148.0.0/1599.148.0.1 to 99.149.255.25499.149.255.255131,070
20499.150.0.0/1599.150.0.1 to 99.151.255.25499.151.255.255131,070
20599.152.0.0/1599.152.0.1 to 99.153.255.25499.153.255.255131,070
20699.154.0.0/1599.154.0.1 to 99.155.255.25499.155.255.255131,070
20799.156.0.0/1599.156.0.1 to 99.157.255.25499.157.255.255131,070
20899.158.0.0/1599.158.0.1 to 99.159.255.25499.159.255.255131,070
20999.160.0.0/1599.160.0.1 to 99.161.255.25499.161.255.255131,070
21099.162.0.0/1599.162.0.1 to 99.163.255.25499.163.255.255131,070
21199.164.0.0/1599.164.0.1 to 99.165.255.25499.165.255.255131,070
21299.166.0.0/1599.166.0.1 to 99.167.255.25499.167.255.255131,070
21399.168.0.0/1599.168.0.1 to 99.169.255.25499.169.255.255131,070
21499.170.0.0/1599.170.0.1 to 99.171.255.25499.171.255.255131,070
21599.172.0.0/1599.172.0.1 to 99.173.255.25499.173.255.255131,070
21699.174.0.0/1599.174.0.1 to 99.175.255.25499.175.255.255131,070
21799.176.0.0/1599.176.0.1 to 99.177.255.25499.177.255.255131,070
21899.178.0.0/1599.178.0.1 to 99.179.255.25499.179.255.255131,070
21999.180.0.0/1599.180.0.1 to 99.181.255.25499.181.255.255131,070
22099.182.0.0/1599.182.0.1 to 99.183.255.25499.183.255.255131,070
22199.184.0.0/1599.184.0.1 to 99.185.255.25499.185.255.255131,070
22299.186.0.0/1599.186.0.1 to 99.187.255.25499.187.255.255131,070
22399.188.0.0/1599.188.0.1 to 99.189.255.25499.189.255.255131,070
22499.190.0.0/1599.190.0.1 to 99.191.255.25499.191.255.255131,070
22599.192.0.0/1599.192.0.1 to 99.193.255.25499.193.255.255131,070
22699.194.0.0/1599.194.0.1 to 99.195.255.25499.195.255.255131,070
22799.196.0.0/1599.196.0.1 to 99.197.255.25499.197.255.255131,070
22899.198.0.0/1599.198.0.1 to 99.199.255.25499.199.255.255131,070
22999.200.0.0/1599.200.0.1 to 99.201.255.25499.201.255.255131,070
23099.202.0.0/1599.202.0.1 to 99.203.255.25499.203.255.255131,070
23199.204.0.0/1599.204.0.1 to 99.205.255.25499.205.255.255131,070
23299.206.0.0/1599.206.0.1 to 99.207.255.25499.207.255.255131,070
23399.208.0.0/1599.208.0.1 to 99.209.255.25499.209.255.255131,070
23499.210.0.0/1599.210.0.1 to 99.211.255.25499.211.255.255131,070
23599.212.0.0/1599.212.0.1 to 99.213.255.25499.213.255.255131,070
23699.214.0.0/1599.214.0.1 to 99.215.255.25499.215.255.255131,070
23799.216.0.0/1599.216.0.1 to 99.217.255.25499.217.255.255131,070
23899.218.0.0/1599.218.0.1 to 99.219.255.25499.219.255.255131,070
23999.220.0.0/1599.220.0.1 to 99.221.255.25499.221.255.255131,070
24099.222.0.0/1599.222.0.1 to 99.223.255.25499.223.255.255131,070
24199.224.0.0/1599.224.0.1 to 99.225.255.25499.225.255.255131,070
24299.226.0.0/1599.226.0.1 to 99.227.255.25499.227.255.255131,070
24399.228.0.0/1599.228.0.1 to 99.229.255.25499.229.255.255131,070
24499.230.0.0/1599.230.0.1 to 99.231.255.25499.231.255.255131,070
24599.232.0.0/1599.232.0.1 to 99.233.255.25499.233.255.255131,070
24699.234.0.0/1599.234.0.1 to 99.235.255.25499.235.255.255131,070
24799.236.0.0/1599.236.0.1 to 99.237.255.25499.237.255.255131,070
24899.238.0.0/1599.238.0.1 to 99.239.255.25499.239.255.255131,070
24999.240.0.0/1599.240.0.1 to 99.241.255.25499.241.255.255131,070
25099.242.0.0/1599.242.0.1 to 99.243.255.25499.243.255.255131,070
25199.244.0.0/1599.244.0.1 to 99.245.255.25499.245.255.255131,070
25299.246.0.0/1599.246.0.1 to 99.247.255.25499.247.255.255131,070
25399.248.0.0/1599.248.0.1 to 99.249.255.25499.249.255.255131,070
25499.250.0.0/1599.250.0.1 to 99.251.255.25499.251.255.255131,070
25599.252.0.0/1599.252.0.1 to 99.253.255.25499.253.255.255131,070
25699.254.0.0/1599.254.0.1 to 99.255.255.25499.255.255.255131,070

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.