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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.

Network96.0.0.0/3
Usable hosts536,870,910
Subnet mask224.0.0.0
Addresses536,870,912
Network address
96.0.0.0
Broadcast address
127.255.255.255
First usable
96.0.0.1
Last usable
127.255.255.254
Usable hosts
536,870,910 (536,870,912 less the network and broadcast addresses)
Subnet mask
224.0.0.0
Wildcard mask
31.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/3
Type
Public public
Old class
A (default /8)
As numbers
Hex 60000000 · Integer 1610612736 to 2147483647
Reverse DNS zones
96.in-addr.arpa
97.in-addr.arpa
98.in-addr.arpa
99.in-addr.arpa
100.in-addr.arpa
101.in-addr.arpa
102.in-addr.arpa
103.in-addr.arpa
104.in-addr.arpa
105.in-addr.arpa
106.in-addr.arpa
107.in-addr.arpa
108.in-addr.arpa
109.in-addr.arpa
110.in-addr.arpa
111.in-addr.arpa
and 16 more
/3 is not on a 8-bit boundary, so it takes 32 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01100000.00000000.00000000.0000000096.0.0.0
Subnet mask11100000.00000000.00000000.00000000224.0.0.0
Network01100000.00000000.00000000.0000000096.0.0.0
Broadcast01111111.11111111.11111111.11111111127.255.255.255
Split into smaller subnets/14
/4 (2)/5 (4)/6 (8)/7 (16)/8 (32)/9 (64)/10 (128)/11 (256)/12 (512)/13 (1,024)/14 (2,048)/15 (4,096)

96.0.0.0/3 makes 2,048 subnets of /14; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
196.0.0.0/1496.0.0.1 to 96.3.255.25496.3.255.255262,142
296.4.0.0/1496.4.0.1 to 96.7.255.25496.7.255.255262,142
396.8.0.0/1496.8.0.1 to 96.11.255.25496.11.255.255262,142
496.12.0.0/1496.12.0.1 to 96.15.255.25496.15.255.255262,142
596.16.0.0/1496.16.0.1 to 96.19.255.25496.19.255.255262,142
696.20.0.0/1496.20.0.1 to 96.23.255.25496.23.255.255262,142
796.24.0.0/1496.24.0.1 to 96.27.255.25496.27.255.255262,142
896.28.0.0/1496.28.0.1 to 96.31.255.25496.31.255.255262,142
996.32.0.0/1496.32.0.1 to 96.35.255.25496.35.255.255262,142
1096.36.0.0/1496.36.0.1 to 96.39.255.25496.39.255.255262,142
1196.40.0.0/1496.40.0.1 to 96.43.255.25496.43.255.255262,142
1296.44.0.0/1496.44.0.1 to 96.47.255.25496.47.255.255262,142
1396.48.0.0/1496.48.0.1 to 96.51.255.25496.51.255.255262,142
1496.52.0.0/1496.52.0.1 to 96.55.255.25496.55.255.255262,142
1596.56.0.0/1496.56.0.1 to 96.59.255.25496.59.255.255262,142
1696.60.0.0/1496.60.0.1 to 96.63.255.25496.63.255.255262,142
1796.64.0.0/1496.64.0.1 to 96.67.255.25496.67.255.255262,142
1896.68.0.0/1496.68.0.1 to 96.71.255.25496.71.255.255262,142
1996.72.0.0/1496.72.0.1 to 96.75.255.25496.75.255.255262,142
2096.76.0.0/1496.76.0.1 to 96.79.255.25496.79.255.255262,142
2196.80.0.0/1496.80.0.1 to 96.83.255.25496.83.255.255262,142
2296.84.0.0/1496.84.0.1 to 96.87.255.25496.87.255.255262,142
2396.88.0.0/1496.88.0.1 to 96.91.255.25496.91.255.255262,142
2496.92.0.0/1496.92.0.1 to 96.95.255.25496.95.255.255262,142
2596.96.0.0/1496.96.0.1 to 96.99.255.25496.99.255.255262,142
2696.100.0.0/1496.100.0.1 to 96.103.255.25496.103.255.255262,142
2796.104.0.0/1496.104.0.1 to 96.107.255.25496.107.255.255262,142
2896.108.0.0/1496.108.0.1 to 96.111.255.25496.111.255.255262,142
2996.112.0.0/1496.112.0.1 to 96.115.255.25496.115.255.255262,142
3096.116.0.0/1496.116.0.1 to 96.119.255.25496.119.255.255262,142
3196.120.0.0/1496.120.0.1 to 96.123.255.25496.123.255.255262,142
3296.124.0.0/1496.124.0.1 to 96.127.255.25496.127.255.255262,142
3396.128.0.0/1496.128.0.1 to 96.131.255.25496.131.255.255262,142
3496.132.0.0/1496.132.0.1 to 96.135.255.25496.135.255.255262,142
3596.136.0.0/1496.136.0.1 to 96.139.255.25496.139.255.255262,142
3696.140.0.0/1496.140.0.1 to 96.143.255.25496.143.255.255262,142
3796.144.0.0/1496.144.0.1 to 96.147.255.25496.147.255.255262,142
3896.148.0.0/1496.148.0.1 to 96.151.255.25496.151.255.255262,142
3996.152.0.0/1496.152.0.1 to 96.155.255.25496.155.255.255262,142
4096.156.0.0/1496.156.0.1 to 96.159.255.25496.159.255.255262,142
4196.160.0.0/1496.160.0.1 to 96.163.255.25496.163.255.255262,142
4296.164.0.0/1496.164.0.1 to 96.167.255.25496.167.255.255262,142
4396.168.0.0/1496.168.0.1 to 96.171.255.25496.171.255.255262,142
4496.172.0.0/1496.172.0.1 to 96.175.255.25496.175.255.255262,142
4596.176.0.0/1496.176.0.1 to 96.179.255.25496.179.255.255262,142
4696.180.0.0/1496.180.0.1 to 96.183.255.25496.183.255.255262,142
4796.184.0.0/1496.184.0.1 to 96.187.255.25496.187.255.255262,142
4896.188.0.0/1496.188.0.1 to 96.191.255.25496.191.255.255262,142
4996.192.0.0/1496.192.0.1 to 96.195.255.25496.195.255.255262,142
5096.196.0.0/1496.196.0.1 to 96.199.255.25496.199.255.255262,142
5196.200.0.0/1496.200.0.1 to 96.203.255.25496.203.255.255262,142
5296.204.0.0/1496.204.0.1 to 96.207.255.25496.207.255.255262,142
5396.208.0.0/1496.208.0.1 to 96.211.255.25496.211.255.255262,142
5496.212.0.0/1496.212.0.1 to 96.215.255.25496.215.255.255262,142
5596.216.0.0/1496.216.0.1 to 96.219.255.25496.219.255.255262,142
5696.220.0.0/1496.220.0.1 to 96.223.255.25496.223.255.255262,142
5796.224.0.0/1496.224.0.1 to 96.227.255.25496.227.255.255262,142
5896.228.0.0/1496.228.0.1 to 96.231.255.25496.231.255.255262,142
5996.232.0.0/1496.232.0.1 to 96.235.255.25496.235.255.255262,142
6096.236.0.0/1496.236.0.1 to 96.239.255.25496.239.255.255262,142
6196.240.0.0/1496.240.0.1 to 96.243.255.25496.243.255.255262,142
6296.244.0.0/1496.244.0.1 to 96.247.255.25496.247.255.255262,142
6396.248.0.0/1496.248.0.1 to 96.251.255.25496.251.255.255262,142
6496.252.0.0/1496.252.0.1 to 96.255.255.25496.255.255.255262,142
6597.0.0.0/1497.0.0.1 to 97.3.255.25497.3.255.255262,142
6697.4.0.0/1497.4.0.1 to 97.7.255.25497.7.255.255262,142
6797.8.0.0/1497.8.0.1 to 97.11.255.25497.11.255.255262,142
6897.12.0.0/1497.12.0.1 to 97.15.255.25497.15.255.255262,142
6997.16.0.0/1497.16.0.1 to 97.19.255.25497.19.255.255262,142
7097.20.0.0/1497.20.0.1 to 97.23.255.25497.23.255.255262,142
7197.24.0.0/1497.24.0.1 to 97.27.255.25497.27.255.255262,142
7297.28.0.0/1497.28.0.1 to 97.31.255.25497.31.255.255262,142
7397.32.0.0/1497.32.0.1 to 97.35.255.25497.35.255.255262,142
7497.36.0.0/1497.36.0.1 to 97.39.255.25497.39.255.255262,142
7597.40.0.0/1497.40.0.1 to 97.43.255.25497.43.255.255262,142
7697.44.0.0/1497.44.0.1 to 97.47.255.25497.47.255.255262,142
7797.48.0.0/1497.48.0.1 to 97.51.255.25497.51.255.255262,142
7897.52.0.0/1497.52.0.1 to 97.55.255.25497.55.255.255262,142
7997.56.0.0/1497.56.0.1 to 97.59.255.25497.59.255.255262,142
8097.60.0.0/1497.60.0.1 to 97.63.255.25497.63.255.255262,142
8197.64.0.0/1497.64.0.1 to 97.67.255.25497.67.255.255262,142
8297.68.0.0/1497.68.0.1 to 97.71.255.25497.71.255.255262,142
8397.72.0.0/1497.72.0.1 to 97.75.255.25497.75.255.255262,142
8497.76.0.0/1497.76.0.1 to 97.79.255.25497.79.255.255262,142
8597.80.0.0/1497.80.0.1 to 97.83.255.25497.83.255.255262,142
8697.84.0.0/1497.84.0.1 to 97.87.255.25497.87.255.255262,142
8797.88.0.0/1497.88.0.1 to 97.91.255.25497.91.255.255262,142
8897.92.0.0/1497.92.0.1 to 97.95.255.25497.95.255.255262,142
8997.96.0.0/1497.96.0.1 to 97.99.255.25497.99.255.255262,142
9097.100.0.0/1497.100.0.1 to 97.103.255.25497.103.255.255262,142
9197.104.0.0/1497.104.0.1 to 97.107.255.25497.107.255.255262,142
9297.108.0.0/1497.108.0.1 to 97.111.255.25497.111.255.255262,142
9397.112.0.0/1497.112.0.1 to 97.115.255.25497.115.255.255262,142
9497.116.0.0/1497.116.0.1 to 97.119.255.25497.119.255.255262,142
9597.120.0.0/1497.120.0.1 to 97.123.255.25497.123.255.255262,142
9697.124.0.0/1497.124.0.1 to 97.127.255.25497.127.255.255262,142
9797.128.0.0/1497.128.0.1 to 97.131.255.25497.131.255.255262,142
9897.132.0.0/1497.132.0.1 to 97.135.255.25497.135.255.255262,142
9997.136.0.0/1497.136.0.1 to 97.139.255.25497.139.255.255262,142
10097.140.0.0/1497.140.0.1 to 97.143.255.25497.143.255.255262,142
10197.144.0.0/1497.144.0.1 to 97.147.255.25497.147.255.255262,142
10297.148.0.0/1497.148.0.1 to 97.151.255.25497.151.255.255262,142
10397.152.0.0/1497.152.0.1 to 97.155.255.25497.155.255.255262,142
10497.156.0.0/1497.156.0.1 to 97.159.255.25497.159.255.255262,142
10597.160.0.0/1497.160.0.1 to 97.163.255.25497.163.255.255262,142
10697.164.0.0/1497.164.0.1 to 97.167.255.25497.167.255.255262,142
10797.168.0.0/1497.168.0.1 to 97.171.255.25497.171.255.255262,142
10897.172.0.0/1497.172.0.1 to 97.175.255.25497.175.255.255262,142
10997.176.0.0/1497.176.0.1 to 97.179.255.25497.179.255.255262,142
11097.180.0.0/1497.180.0.1 to 97.183.255.25497.183.255.255262,142
11197.184.0.0/1497.184.0.1 to 97.187.255.25497.187.255.255262,142
11297.188.0.0/1497.188.0.1 to 97.191.255.25497.191.255.255262,142
11397.192.0.0/1497.192.0.1 to 97.195.255.25497.195.255.255262,142
11497.196.0.0/1497.196.0.1 to 97.199.255.25497.199.255.255262,142
11597.200.0.0/1497.200.0.1 to 97.203.255.25497.203.255.255262,142
11697.204.0.0/1497.204.0.1 to 97.207.255.25497.207.255.255262,142
11797.208.0.0/1497.208.0.1 to 97.211.255.25497.211.255.255262,142
11897.212.0.0/1497.212.0.1 to 97.215.255.25497.215.255.255262,142
11997.216.0.0/1497.216.0.1 to 97.219.255.25497.219.255.255262,142
12097.220.0.0/1497.220.0.1 to 97.223.255.25497.223.255.255262,142
12197.224.0.0/1497.224.0.1 to 97.227.255.25497.227.255.255262,142
12297.228.0.0/1497.228.0.1 to 97.231.255.25497.231.255.255262,142
12397.232.0.0/1497.232.0.1 to 97.235.255.25497.235.255.255262,142
12497.236.0.0/1497.236.0.1 to 97.239.255.25497.239.255.255262,142
12597.240.0.0/1497.240.0.1 to 97.243.255.25497.243.255.255262,142
12697.244.0.0/1497.244.0.1 to 97.247.255.25497.247.255.255262,142
12797.248.0.0/1497.248.0.1 to 97.251.255.25497.251.255.255262,142
12897.252.0.0/1497.252.0.1 to 97.255.255.25497.255.255.255262,142
12998.0.0.0/1498.0.0.1 to 98.3.255.25498.3.255.255262,142
13098.4.0.0/1498.4.0.1 to 98.7.255.25498.7.255.255262,142
13198.8.0.0/1498.8.0.1 to 98.11.255.25498.11.255.255262,142
13298.12.0.0/1498.12.0.1 to 98.15.255.25498.15.255.255262,142
13398.16.0.0/1498.16.0.1 to 98.19.255.25498.19.255.255262,142
13498.20.0.0/1498.20.0.1 to 98.23.255.25498.23.255.255262,142
13598.24.0.0/1498.24.0.1 to 98.27.255.25498.27.255.255262,142
13698.28.0.0/1498.28.0.1 to 98.31.255.25498.31.255.255262,142
13798.32.0.0/1498.32.0.1 to 98.35.255.25498.35.255.255262,142
13898.36.0.0/1498.36.0.1 to 98.39.255.25498.39.255.255262,142
13998.40.0.0/1498.40.0.1 to 98.43.255.25498.43.255.255262,142
14098.44.0.0/1498.44.0.1 to 98.47.255.25498.47.255.255262,142
14198.48.0.0/1498.48.0.1 to 98.51.255.25498.51.255.255262,142
14298.52.0.0/1498.52.0.1 to 98.55.255.25498.55.255.255262,142
14398.56.0.0/1498.56.0.1 to 98.59.255.25498.59.255.255262,142
14498.60.0.0/1498.60.0.1 to 98.63.255.25498.63.255.255262,142
14598.64.0.0/1498.64.0.1 to 98.67.255.25498.67.255.255262,142
14698.68.0.0/1498.68.0.1 to 98.71.255.25498.71.255.255262,142
14798.72.0.0/1498.72.0.1 to 98.75.255.25498.75.255.255262,142
14898.76.0.0/1498.76.0.1 to 98.79.255.25498.79.255.255262,142
14998.80.0.0/1498.80.0.1 to 98.83.255.25498.83.255.255262,142
15098.84.0.0/1498.84.0.1 to 98.87.255.25498.87.255.255262,142
15198.88.0.0/1498.88.0.1 to 98.91.255.25498.91.255.255262,142
15298.92.0.0/1498.92.0.1 to 98.95.255.25498.95.255.255262,142
15398.96.0.0/1498.96.0.1 to 98.99.255.25498.99.255.255262,142
15498.100.0.0/1498.100.0.1 to 98.103.255.25498.103.255.255262,142
15598.104.0.0/1498.104.0.1 to 98.107.255.25498.107.255.255262,142
15698.108.0.0/1498.108.0.1 to 98.111.255.25498.111.255.255262,142
15798.112.0.0/1498.112.0.1 to 98.115.255.25498.115.255.255262,142
15898.116.0.0/1498.116.0.1 to 98.119.255.25498.119.255.255262,142
15998.120.0.0/1498.120.0.1 to 98.123.255.25498.123.255.255262,142
16098.124.0.0/1498.124.0.1 to 98.127.255.25498.127.255.255262,142
16198.128.0.0/1498.128.0.1 to 98.131.255.25498.131.255.255262,142
16298.132.0.0/1498.132.0.1 to 98.135.255.25498.135.255.255262,142
16398.136.0.0/1498.136.0.1 to 98.139.255.25498.139.255.255262,142
16498.140.0.0/1498.140.0.1 to 98.143.255.25498.143.255.255262,142
16598.144.0.0/1498.144.0.1 to 98.147.255.25498.147.255.255262,142
16698.148.0.0/1498.148.0.1 to 98.151.255.25498.151.255.255262,142
16798.152.0.0/1498.152.0.1 to 98.155.255.25498.155.255.255262,142
16898.156.0.0/1498.156.0.1 to 98.159.255.25498.159.255.255262,142
16998.160.0.0/1498.160.0.1 to 98.163.255.25498.163.255.255262,142
17098.164.0.0/1498.164.0.1 to 98.167.255.25498.167.255.255262,142
17198.168.0.0/1498.168.0.1 to 98.171.255.25498.171.255.255262,142
17298.172.0.0/1498.172.0.1 to 98.175.255.25498.175.255.255262,142
17398.176.0.0/1498.176.0.1 to 98.179.255.25498.179.255.255262,142
17498.180.0.0/1498.180.0.1 to 98.183.255.25498.183.255.255262,142
17598.184.0.0/1498.184.0.1 to 98.187.255.25498.187.255.255262,142
17698.188.0.0/1498.188.0.1 to 98.191.255.25498.191.255.255262,142
17798.192.0.0/1498.192.0.1 to 98.195.255.25498.195.255.255262,142
17898.196.0.0/1498.196.0.1 to 98.199.255.25498.199.255.255262,142
17998.200.0.0/1498.200.0.1 to 98.203.255.25498.203.255.255262,142
18098.204.0.0/1498.204.0.1 to 98.207.255.25498.207.255.255262,142
18198.208.0.0/1498.208.0.1 to 98.211.255.25498.211.255.255262,142
18298.212.0.0/1498.212.0.1 to 98.215.255.25498.215.255.255262,142
18398.216.0.0/1498.216.0.1 to 98.219.255.25498.219.255.255262,142
18498.220.0.0/1498.220.0.1 to 98.223.255.25498.223.255.255262,142
18598.224.0.0/1498.224.0.1 to 98.227.255.25498.227.255.255262,142
18698.228.0.0/1498.228.0.1 to 98.231.255.25498.231.255.255262,142
18798.232.0.0/1498.232.0.1 to 98.235.255.25498.235.255.255262,142
18898.236.0.0/1498.236.0.1 to 98.239.255.25498.239.255.255262,142
18998.240.0.0/1498.240.0.1 to 98.243.255.25498.243.255.255262,142
19098.244.0.0/1498.244.0.1 to 98.247.255.25498.247.255.255262,142
19198.248.0.0/1498.248.0.1 to 98.251.255.25498.251.255.255262,142
19298.252.0.0/1498.252.0.1 to 98.255.255.25498.255.255.255262,142
19399.0.0.0/1499.0.0.1 to 99.3.255.25499.3.255.255262,142
19499.4.0.0/1499.4.0.1 to 99.7.255.25499.7.255.255262,142
19599.8.0.0/1499.8.0.1 to 99.11.255.25499.11.255.255262,142
19699.12.0.0/1499.12.0.1 to 99.15.255.25499.15.255.255262,142
19799.16.0.0/1499.16.0.1 to 99.19.255.25499.19.255.255262,142
19899.20.0.0/1499.20.0.1 to 99.23.255.25499.23.255.255262,142
19999.24.0.0/1499.24.0.1 to 99.27.255.25499.27.255.255262,142
20099.28.0.0/1499.28.0.1 to 99.31.255.25499.31.255.255262,142
20199.32.0.0/1499.32.0.1 to 99.35.255.25499.35.255.255262,142
20299.36.0.0/1499.36.0.1 to 99.39.255.25499.39.255.255262,142
20399.40.0.0/1499.40.0.1 to 99.43.255.25499.43.255.255262,142
20499.44.0.0/1499.44.0.1 to 99.47.255.25499.47.255.255262,142
20599.48.0.0/1499.48.0.1 to 99.51.255.25499.51.255.255262,142
20699.52.0.0/1499.52.0.1 to 99.55.255.25499.55.255.255262,142
20799.56.0.0/1499.56.0.1 to 99.59.255.25499.59.255.255262,142
20899.60.0.0/1499.60.0.1 to 99.63.255.25499.63.255.255262,142
20999.64.0.0/1499.64.0.1 to 99.67.255.25499.67.255.255262,142
21099.68.0.0/1499.68.0.1 to 99.71.255.25499.71.255.255262,142
21199.72.0.0/1499.72.0.1 to 99.75.255.25499.75.255.255262,142
21299.76.0.0/1499.76.0.1 to 99.79.255.25499.79.255.255262,142
21399.80.0.0/1499.80.0.1 to 99.83.255.25499.83.255.255262,142
21499.84.0.0/1499.84.0.1 to 99.87.255.25499.87.255.255262,142
21599.88.0.0/1499.88.0.1 to 99.91.255.25499.91.255.255262,142
21699.92.0.0/1499.92.0.1 to 99.95.255.25499.95.255.255262,142
21799.96.0.0/1499.96.0.1 to 99.99.255.25499.99.255.255262,142
21899.100.0.0/1499.100.0.1 to 99.103.255.25499.103.255.255262,142
21999.104.0.0/1499.104.0.1 to 99.107.255.25499.107.255.255262,142
22099.108.0.0/1499.108.0.1 to 99.111.255.25499.111.255.255262,142
22199.112.0.0/1499.112.0.1 to 99.115.255.25499.115.255.255262,142
22299.116.0.0/1499.116.0.1 to 99.119.255.25499.119.255.255262,142
22399.120.0.0/1499.120.0.1 to 99.123.255.25499.123.255.255262,142
22499.124.0.0/1499.124.0.1 to 99.127.255.25499.127.255.255262,142
22599.128.0.0/1499.128.0.1 to 99.131.255.25499.131.255.255262,142
22699.132.0.0/1499.132.0.1 to 99.135.255.25499.135.255.255262,142
22799.136.0.0/1499.136.0.1 to 99.139.255.25499.139.255.255262,142
22899.140.0.0/1499.140.0.1 to 99.143.255.25499.143.255.255262,142
22999.144.0.0/1499.144.0.1 to 99.147.255.25499.147.255.255262,142
23099.148.0.0/1499.148.0.1 to 99.151.255.25499.151.255.255262,142
23199.152.0.0/1499.152.0.1 to 99.155.255.25499.155.255.255262,142
23299.156.0.0/1499.156.0.1 to 99.159.255.25499.159.255.255262,142
23399.160.0.0/1499.160.0.1 to 99.163.255.25499.163.255.255262,142
23499.164.0.0/1499.164.0.1 to 99.167.255.25499.167.255.255262,142
23599.168.0.0/1499.168.0.1 to 99.171.255.25499.171.255.255262,142
23699.172.0.0/1499.172.0.1 to 99.175.255.25499.175.255.255262,142
23799.176.0.0/1499.176.0.1 to 99.179.255.25499.179.255.255262,142
23899.180.0.0/1499.180.0.1 to 99.183.255.25499.183.255.255262,142
23999.184.0.0/1499.184.0.1 to 99.187.255.25499.187.255.255262,142
24099.188.0.0/1499.188.0.1 to 99.191.255.25499.191.255.255262,142
24199.192.0.0/1499.192.0.1 to 99.195.255.25499.195.255.255262,142
24299.196.0.0/1499.196.0.1 to 99.199.255.25499.199.255.255262,142
24399.200.0.0/1499.200.0.1 to 99.203.255.25499.203.255.255262,142
24499.204.0.0/1499.204.0.1 to 99.207.255.25499.207.255.255262,142
24599.208.0.0/1499.208.0.1 to 99.211.255.25499.211.255.255262,142
24699.212.0.0/1499.212.0.1 to 99.215.255.25499.215.255.255262,142
24799.216.0.0/1499.216.0.1 to 99.219.255.25499.219.255.255262,142
24899.220.0.0/1499.220.0.1 to 99.223.255.25499.223.255.255262,142
24999.224.0.0/1499.224.0.1 to 99.227.255.25499.227.255.255262,142
25099.228.0.0/1499.228.0.1 to 99.231.255.25499.231.255.255262,142
25199.232.0.0/1499.232.0.1 to 99.235.255.25499.235.255.255262,142
25299.236.0.0/1499.236.0.1 to 99.239.255.25499.239.255.255262,142
25399.240.0.0/1499.240.0.1 to 99.243.255.25499.243.255.255262,142
25499.244.0.0/1499.244.0.1 to 99.247.255.25499.247.255.255262,142
25599.248.0.0/1499.248.0.1 to 99.251.255.25499.251.255.255262,142
25699.252.0.0/1499.252.0.1 to 99.255.255.25499.255.255.255262,142

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.