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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.

Network63.32.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
63.32.0.0
Broadcast address
63.63.255.255
First usable
63.32.0.1
Last usable
63.63.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Public public
Old class
A (default /8)
As numbers
Hex 3F200000 · Integer 1059061760 to 1061158911
Reverse DNS zones
32.63.in-addr.arpa
33.63.in-addr.arpa
34.63.in-addr.arpa
35.63.in-addr.arpa
36.63.in-addr.arpa
37.63.in-addr.arpa
38.63.in-addr.arpa
39.63.in-addr.arpa
40.63.in-addr.arpa
41.63.in-addr.arpa
42.63.in-addr.arpa
43.63.in-addr.arpa
44.63.in-addr.arpa
45.63.in-addr.arpa
46.63.in-addr.arpa
47.63.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00111111.00100000.00000000.0000000063.32.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network00111111.00100000.00000000.0000000063.32.0.0
Broadcast00111111.00111111.11111111.1111111163.63.255.255
Split into smaller subnets/23
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

63.32.0.0/11 makes 4,096 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
163.32.0.0/2363.32.0.1 to 63.32.1.25463.32.1.255510
263.32.2.0/2363.32.2.1 to 63.32.3.25463.32.3.255510
363.32.4.0/2363.32.4.1 to 63.32.5.25463.32.5.255510
463.32.6.0/2363.32.6.1 to 63.32.7.25463.32.7.255510
563.32.8.0/2363.32.8.1 to 63.32.9.25463.32.9.255510
663.32.10.0/2363.32.10.1 to 63.32.11.25463.32.11.255510
763.32.12.0/2363.32.12.1 to 63.32.13.25463.32.13.255510
863.32.14.0/2363.32.14.1 to 63.32.15.25463.32.15.255510
963.32.16.0/2363.32.16.1 to 63.32.17.25463.32.17.255510
1063.32.18.0/2363.32.18.1 to 63.32.19.25463.32.19.255510
1163.32.20.0/2363.32.20.1 to 63.32.21.25463.32.21.255510
1263.32.22.0/2363.32.22.1 to 63.32.23.25463.32.23.255510
1363.32.24.0/2363.32.24.1 to 63.32.25.25463.32.25.255510
1463.32.26.0/2363.32.26.1 to 63.32.27.25463.32.27.255510
1563.32.28.0/2363.32.28.1 to 63.32.29.25463.32.29.255510
1663.32.30.0/2363.32.30.1 to 63.32.31.25463.32.31.255510
1763.32.32.0/2363.32.32.1 to 63.32.33.25463.32.33.255510
1863.32.34.0/2363.32.34.1 to 63.32.35.25463.32.35.255510
1963.32.36.0/2363.32.36.1 to 63.32.37.25463.32.37.255510
2063.32.38.0/2363.32.38.1 to 63.32.39.25463.32.39.255510
2163.32.40.0/2363.32.40.1 to 63.32.41.25463.32.41.255510
2263.32.42.0/2363.32.42.1 to 63.32.43.25463.32.43.255510
2363.32.44.0/2363.32.44.1 to 63.32.45.25463.32.45.255510
2463.32.46.0/2363.32.46.1 to 63.32.47.25463.32.47.255510
2563.32.48.0/2363.32.48.1 to 63.32.49.25463.32.49.255510
2663.32.50.0/2363.32.50.1 to 63.32.51.25463.32.51.255510
2763.32.52.0/2363.32.52.1 to 63.32.53.25463.32.53.255510
2863.32.54.0/2363.32.54.1 to 63.32.55.25463.32.55.255510
2963.32.56.0/2363.32.56.1 to 63.32.57.25463.32.57.255510
3063.32.58.0/2363.32.58.1 to 63.32.59.25463.32.59.255510
3163.32.60.0/2363.32.60.1 to 63.32.61.25463.32.61.255510
3263.32.62.0/2363.32.62.1 to 63.32.63.25463.32.63.255510
3363.32.64.0/2363.32.64.1 to 63.32.65.25463.32.65.255510
3463.32.66.0/2363.32.66.1 to 63.32.67.25463.32.67.255510
3563.32.68.0/2363.32.68.1 to 63.32.69.25463.32.69.255510
3663.32.70.0/2363.32.70.1 to 63.32.71.25463.32.71.255510
3763.32.72.0/2363.32.72.1 to 63.32.73.25463.32.73.255510
3863.32.74.0/2363.32.74.1 to 63.32.75.25463.32.75.255510
3963.32.76.0/2363.32.76.1 to 63.32.77.25463.32.77.255510
4063.32.78.0/2363.32.78.1 to 63.32.79.25463.32.79.255510
4163.32.80.0/2363.32.80.1 to 63.32.81.25463.32.81.255510
4263.32.82.0/2363.32.82.1 to 63.32.83.25463.32.83.255510
4363.32.84.0/2363.32.84.1 to 63.32.85.25463.32.85.255510
4463.32.86.0/2363.32.86.1 to 63.32.87.25463.32.87.255510
4563.32.88.0/2363.32.88.1 to 63.32.89.25463.32.89.255510
4663.32.90.0/2363.32.90.1 to 63.32.91.25463.32.91.255510
4763.32.92.0/2363.32.92.1 to 63.32.93.25463.32.93.255510
4863.32.94.0/2363.32.94.1 to 63.32.95.25463.32.95.255510
4963.32.96.0/2363.32.96.1 to 63.32.97.25463.32.97.255510
5063.32.98.0/2363.32.98.1 to 63.32.99.25463.32.99.255510
5163.32.100.0/2363.32.100.1 to 63.32.101.25463.32.101.255510
5263.32.102.0/2363.32.102.1 to 63.32.103.25463.32.103.255510
5363.32.104.0/2363.32.104.1 to 63.32.105.25463.32.105.255510
5463.32.106.0/2363.32.106.1 to 63.32.107.25463.32.107.255510
5563.32.108.0/2363.32.108.1 to 63.32.109.25463.32.109.255510
5663.32.110.0/2363.32.110.1 to 63.32.111.25463.32.111.255510
5763.32.112.0/2363.32.112.1 to 63.32.113.25463.32.113.255510
5863.32.114.0/2363.32.114.1 to 63.32.115.25463.32.115.255510
5963.32.116.0/2363.32.116.1 to 63.32.117.25463.32.117.255510
6063.32.118.0/2363.32.118.1 to 63.32.119.25463.32.119.255510
6163.32.120.0/2363.32.120.1 to 63.32.121.25463.32.121.255510
6263.32.122.0/2363.32.122.1 to 63.32.123.25463.32.123.255510
6363.32.124.0/2363.32.124.1 to 63.32.125.25463.32.125.255510
6463.32.126.0/2363.32.126.1 to 63.32.127.25463.32.127.255510
6563.32.128.0/2363.32.128.1 to 63.32.129.25463.32.129.255510
6663.32.130.0/2363.32.130.1 to 63.32.131.25463.32.131.255510
6763.32.132.0/2363.32.132.1 to 63.32.133.25463.32.133.255510
6863.32.134.0/2363.32.134.1 to 63.32.135.25463.32.135.255510
6963.32.136.0/2363.32.136.1 to 63.32.137.25463.32.137.255510
7063.32.138.0/2363.32.138.1 to 63.32.139.25463.32.139.255510
7163.32.140.0/2363.32.140.1 to 63.32.141.25463.32.141.255510
7263.32.142.0/2363.32.142.1 to 63.32.143.25463.32.143.255510
7363.32.144.0/2363.32.144.1 to 63.32.145.25463.32.145.255510
7463.32.146.0/2363.32.146.1 to 63.32.147.25463.32.147.255510
7563.32.148.0/2363.32.148.1 to 63.32.149.25463.32.149.255510
7663.32.150.0/2363.32.150.1 to 63.32.151.25463.32.151.255510
7763.32.152.0/2363.32.152.1 to 63.32.153.25463.32.153.255510
7863.32.154.0/2363.32.154.1 to 63.32.155.25463.32.155.255510
7963.32.156.0/2363.32.156.1 to 63.32.157.25463.32.157.255510
8063.32.158.0/2363.32.158.1 to 63.32.159.25463.32.159.255510
8163.32.160.0/2363.32.160.1 to 63.32.161.25463.32.161.255510
8263.32.162.0/2363.32.162.1 to 63.32.163.25463.32.163.255510
8363.32.164.0/2363.32.164.1 to 63.32.165.25463.32.165.255510
8463.32.166.0/2363.32.166.1 to 63.32.167.25463.32.167.255510
8563.32.168.0/2363.32.168.1 to 63.32.169.25463.32.169.255510
8663.32.170.0/2363.32.170.1 to 63.32.171.25463.32.171.255510
8763.32.172.0/2363.32.172.1 to 63.32.173.25463.32.173.255510
8863.32.174.0/2363.32.174.1 to 63.32.175.25463.32.175.255510
8963.32.176.0/2363.32.176.1 to 63.32.177.25463.32.177.255510
9063.32.178.0/2363.32.178.1 to 63.32.179.25463.32.179.255510
9163.32.180.0/2363.32.180.1 to 63.32.181.25463.32.181.255510
9263.32.182.0/2363.32.182.1 to 63.32.183.25463.32.183.255510
9363.32.184.0/2363.32.184.1 to 63.32.185.25463.32.185.255510
9463.32.186.0/2363.32.186.1 to 63.32.187.25463.32.187.255510
9563.32.188.0/2363.32.188.1 to 63.32.189.25463.32.189.255510
9663.32.190.0/2363.32.190.1 to 63.32.191.25463.32.191.255510
9763.32.192.0/2363.32.192.1 to 63.32.193.25463.32.193.255510
9863.32.194.0/2363.32.194.1 to 63.32.195.25463.32.195.255510
9963.32.196.0/2363.32.196.1 to 63.32.197.25463.32.197.255510
10063.32.198.0/2363.32.198.1 to 63.32.199.25463.32.199.255510
10163.32.200.0/2363.32.200.1 to 63.32.201.25463.32.201.255510
10263.32.202.0/2363.32.202.1 to 63.32.203.25463.32.203.255510
10363.32.204.0/2363.32.204.1 to 63.32.205.25463.32.205.255510
10463.32.206.0/2363.32.206.1 to 63.32.207.25463.32.207.255510
10563.32.208.0/2363.32.208.1 to 63.32.209.25463.32.209.255510
10663.32.210.0/2363.32.210.1 to 63.32.211.25463.32.211.255510
10763.32.212.0/2363.32.212.1 to 63.32.213.25463.32.213.255510
10863.32.214.0/2363.32.214.1 to 63.32.215.25463.32.215.255510
10963.32.216.0/2363.32.216.1 to 63.32.217.25463.32.217.255510
11063.32.218.0/2363.32.218.1 to 63.32.219.25463.32.219.255510
11163.32.220.0/2363.32.220.1 to 63.32.221.25463.32.221.255510
11263.32.222.0/2363.32.222.1 to 63.32.223.25463.32.223.255510
11363.32.224.0/2363.32.224.1 to 63.32.225.25463.32.225.255510
11463.32.226.0/2363.32.226.1 to 63.32.227.25463.32.227.255510
11563.32.228.0/2363.32.228.1 to 63.32.229.25463.32.229.255510
11663.32.230.0/2363.32.230.1 to 63.32.231.25463.32.231.255510
11763.32.232.0/2363.32.232.1 to 63.32.233.25463.32.233.255510
11863.32.234.0/2363.32.234.1 to 63.32.235.25463.32.235.255510
11963.32.236.0/2363.32.236.1 to 63.32.237.25463.32.237.255510
12063.32.238.0/2363.32.238.1 to 63.32.239.25463.32.239.255510
12163.32.240.0/2363.32.240.1 to 63.32.241.25463.32.241.255510
12263.32.242.0/2363.32.242.1 to 63.32.243.25463.32.243.255510
12363.32.244.0/2363.32.244.1 to 63.32.245.25463.32.245.255510
12463.32.246.0/2363.32.246.1 to 63.32.247.25463.32.247.255510
12563.32.248.0/2363.32.248.1 to 63.32.249.25463.32.249.255510
12663.32.250.0/2363.32.250.1 to 63.32.251.25463.32.251.255510
12763.32.252.0/2363.32.252.1 to 63.32.253.25463.32.253.255510
12863.32.254.0/2363.32.254.1 to 63.32.255.25463.32.255.255510
12963.33.0.0/2363.33.0.1 to 63.33.1.25463.33.1.255510
13063.33.2.0/2363.33.2.1 to 63.33.3.25463.33.3.255510
13163.33.4.0/2363.33.4.1 to 63.33.5.25463.33.5.255510
13263.33.6.0/2363.33.6.1 to 63.33.7.25463.33.7.255510
13363.33.8.0/2363.33.8.1 to 63.33.9.25463.33.9.255510
13463.33.10.0/2363.33.10.1 to 63.33.11.25463.33.11.255510
13563.33.12.0/2363.33.12.1 to 63.33.13.25463.33.13.255510
13663.33.14.0/2363.33.14.1 to 63.33.15.25463.33.15.255510
13763.33.16.0/2363.33.16.1 to 63.33.17.25463.33.17.255510
13863.33.18.0/2363.33.18.1 to 63.33.19.25463.33.19.255510
13963.33.20.0/2363.33.20.1 to 63.33.21.25463.33.21.255510
14063.33.22.0/2363.33.22.1 to 63.33.23.25463.33.23.255510
14163.33.24.0/2363.33.24.1 to 63.33.25.25463.33.25.255510
14263.33.26.0/2363.33.26.1 to 63.33.27.25463.33.27.255510
14363.33.28.0/2363.33.28.1 to 63.33.29.25463.33.29.255510
14463.33.30.0/2363.33.30.1 to 63.33.31.25463.33.31.255510
14563.33.32.0/2363.33.32.1 to 63.33.33.25463.33.33.255510
14663.33.34.0/2363.33.34.1 to 63.33.35.25463.33.35.255510
14763.33.36.0/2363.33.36.1 to 63.33.37.25463.33.37.255510
14863.33.38.0/2363.33.38.1 to 63.33.39.25463.33.39.255510
14963.33.40.0/2363.33.40.1 to 63.33.41.25463.33.41.255510
15063.33.42.0/2363.33.42.1 to 63.33.43.25463.33.43.255510
15163.33.44.0/2363.33.44.1 to 63.33.45.25463.33.45.255510
15263.33.46.0/2363.33.46.1 to 63.33.47.25463.33.47.255510
15363.33.48.0/2363.33.48.1 to 63.33.49.25463.33.49.255510
15463.33.50.0/2363.33.50.1 to 63.33.51.25463.33.51.255510
15563.33.52.0/2363.33.52.1 to 63.33.53.25463.33.53.255510
15663.33.54.0/2363.33.54.1 to 63.33.55.25463.33.55.255510
15763.33.56.0/2363.33.56.1 to 63.33.57.25463.33.57.255510
15863.33.58.0/2363.33.58.1 to 63.33.59.25463.33.59.255510
15963.33.60.0/2363.33.60.1 to 63.33.61.25463.33.61.255510
16063.33.62.0/2363.33.62.1 to 63.33.63.25463.33.63.255510
16163.33.64.0/2363.33.64.1 to 63.33.65.25463.33.65.255510
16263.33.66.0/2363.33.66.1 to 63.33.67.25463.33.67.255510
16363.33.68.0/2363.33.68.1 to 63.33.69.25463.33.69.255510
16463.33.70.0/2363.33.70.1 to 63.33.71.25463.33.71.255510
16563.33.72.0/2363.33.72.1 to 63.33.73.25463.33.73.255510
16663.33.74.0/2363.33.74.1 to 63.33.75.25463.33.75.255510
16763.33.76.0/2363.33.76.1 to 63.33.77.25463.33.77.255510
16863.33.78.0/2363.33.78.1 to 63.33.79.25463.33.79.255510
16963.33.80.0/2363.33.80.1 to 63.33.81.25463.33.81.255510
17063.33.82.0/2363.33.82.1 to 63.33.83.25463.33.83.255510
17163.33.84.0/2363.33.84.1 to 63.33.85.25463.33.85.255510
17263.33.86.0/2363.33.86.1 to 63.33.87.25463.33.87.255510
17363.33.88.0/2363.33.88.1 to 63.33.89.25463.33.89.255510
17463.33.90.0/2363.33.90.1 to 63.33.91.25463.33.91.255510
17563.33.92.0/2363.33.92.1 to 63.33.93.25463.33.93.255510
17663.33.94.0/2363.33.94.1 to 63.33.95.25463.33.95.255510
17763.33.96.0/2363.33.96.1 to 63.33.97.25463.33.97.255510
17863.33.98.0/2363.33.98.1 to 63.33.99.25463.33.99.255510
17963.33.100.0/2363.33.100.1 to 63.33.101.25463.33.101.255510
18063.33.102.0/2363.33.102.1 to 63.33.103.25463.33.103.255510
18163.33.104.0/2363.33.104.1 to 63.33.105.25463.33.105.255510
18263.33.106.0/2363.33.106.1 to 63.33.107.25463.33.107.255510
18363.33.108.0/2363.33.108.1 to 63.33.109.25463.33.109.255510
18463.33.110.0/2363.33.110.1 to 63.33.111.25463.33.111.255510
18563.33.112.0/2363.33.112.1 to 63.33.113.25463.33.113.255510
18663.33.114.0/2363.33.114.1 to 63.33.115.25463.33.115.255510
18763.33.116.0/2363.33.116.1 to 63.33.117.25463.33.117.255510
18863.33.118.0/2363.33.118.1 to 63.33.119.25463.33.119.255510
18963.33.120.0/2363.33.120.1 to 63.33.121.25463.33.121.255510
19063.33.122.0/2363.33.122.1 to 63.33.123.25463.33.123.255510
19163.33.124.0/2363.33.124.1 to 63.33.125.25463.33.125.255510
19263.33.126.0/2363.33.126.1 to 63.33.127.25463.33.127.255510
19363.33.128.0/2363.33.128.1 to 63.33.129.25463.33.129.255510
19463.33.130.0/2363.33.130.1 to 63.33.131.25463.33.131.255510
19563.33.132.0/2363.33.132.1 to 63.33.133.25463.33.133.255510
19663.33.134.0/2363.33.134.1 to 63.33.135.25463.33.135.255510
19763.33.136.0/2363.33.136.1 to 63.33.137.25463.33.137.255510
19863.33.138.0/2363.33.138.1 to 63.33.139.25463.33.139.255510
19963.33.140.0/2363.33.140.1 to 63.33.141.25463.33.141.255510
20063.33.142.0/2363.33.142.1 to 63.33.143.25463.33.143.255510
20163.33.144.0/2363.33.144.1 to 63.33.145.25463.33.145.255510
20263.33.146.0/2363.33.146.1 to 63.33.147.25463.33.147.255510
20363.33.148.0/2363.33.148.1 to 63.33.149.25463.33.149.255510
20463.33.150.0/2363.33.150.1 to 63.33.151.25463.33.151.255510
20563.33.152.0/2363.33.152.1 to 63.33.153.25463.33.153.255510
20663.33.154.0/2363.33.154.1 to 63.33.155.25463.33.155.255510
20763.33.156.0/2363.33.156.1 to 63.33.157.25463.33.157.255510
20863.33.158.0/2363.33.158.1 to 63.33.159.25463.33.159.255510
20963.33.160.0/2363.33.160.1 to 63.33.161.25463.33.161.255510
21063.33.162.0/2363.33.162.1 to 63.33.163.25463.33.163.255510
21163.33.164.0/2363.33.164.1 to 63.33.165.25463.33.165.255510
21263.33.166.0/2363.33.166.1 to 63.33.167.25463.33.167.255510
21363.33.168.0/2363.33.168.1 to 63.33.169.25463.33.169.255510
21463.33.170.0/2363.33.170.1 to 63.33.171.25463.33.171.255510
21563.33.172.0/2363.33.172.1 to 63.33.173.25463.33.173.255510
21663.33.174.0/2363.33.174.1 to 63.33.175.25463.33.175.255510
21763.33.176.0/2363.33.176.1 to 63.33.177.25463.33.177.255510
21863.33.178.0/2363.33.178.1 to 63.33.179.25463.33.179.255510
21963.33.180.0/2363.33.180.1 to 63.33.181.25463.33.181.255510
22063.33.182.0/2363.33.182.1 to 63.33.183.25463.33.183.255510
22163.33.184.0/2363.33.184.1 to 63.33.185.25463.33.185.255510
22263.33.186.0/2363.33.186.1 to 63.33.187.25463.33.187.255510
22363.33.188.0/2363.33.188.1 to 63.33.189.25463.33.189.255510
22463.33.190.0/2363.33.190.1 to 63.33.191.25463.33.191.255510
22563.33.192.0/2363.33.192.1 to 63.33.193.25463.33.193.255510
22663.33.194.0/2363.33.194.1 to 63.33.195.25463.33.195.255510
22763.33.196.0/2363.33.196.1 to 63.33.197.25463.33.197.255510
22863.33.198.0/2363.33.198.1 to 63.33.199.25463.33.199.255510
22963.33.200.0/2363.33.200.1 to 63.33.201.25463.33.201.255510
23063.33.202.0/2363.33.202.1 to 63.33.203.25463.33.203.255510
23163.33.204.0/2363.33.204.1 to 63.33.205.25463.33.205.255510
23263.33.206.0/2363.33.206.1 to 63.33.207.25463.33.207.255510
23363.33.208.0/2363.33.208.1 to 63.33.209.25463.33.209.255510
23463.33.210.0/2363.33.210.1 to 63.33.211.25463.33.211.255510
23563.33.212.0/2363.33.212.1 to 63.33.213.25463.33.213.255510
23663.33.214.0/2363.33.214.1 to 63.33.215.25463.33.215.255510
23763.33.216.0/2363.33.216.1 to 63.33.217.25463.33.217.255510
23863.33.218.0/2363.33.218.1 to 63.33.219.25463.33.219.255510
23963.33.220.0/2363.33.220.1 to 63.33.221.25463.33.221.255510
24063.33.222.0/2363.33.222.1 to 63.33.223.25463.33.223.255510
24163.33.224.0/2363.33.224.1 to 63.33.225.25463.33.225.255510
24263.33.226.0/2363.33.226.1 to 63.33.227.25463.33.227.255510
24363.33.228.0/2363.33.228.1 to 63.33.229.25463.33.229.255510
24463.33.230.0/2363.33.230.1 to 63.33.231.25463.33.231.255510
24563.33.232.0/2363.33.232.1 to 63.33.233.25463.33.233.255510
24663.33.234.0/2363.33.234.1 to 63.33.235.25463.33.235.255510
24763.33.236.0/2363.33.236.1 to 63.33.237.25463.33.237.255510
24863.33.238.0/2363.33.238.1 to 63.33.239.25463.33.239.255510
24963.33.240.0/2363.33.240.1 to 63.33.241.25463.33.241.255510
25063.33.242.0/2363.33.242.1 to 63.33.243.25463.33.243.255510
25163.33.244.0/2363.33.244.1 to 63.33.245.25463.33.245.255510
25263.33.246.0/2363.33.246.1 to 63.33.247.25463.33.247.255510
25363.33.248.0/2363.33.248.1 to 63.33.249.25463.33.249.255510
25463.33.250.0/2363.33.250.1 to 63.33.251.25463.33.251.255510
25563.33.252.0/2363.33.252.1 to 63.33.253.25463.33.253.255510
25663.33.254.0/2363.33.254.1 to 63.33.255.25463.33.255.255510

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.