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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.

Network63.32.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
63.32.0.0
Broadcast address
63.39.255.255
First usable
63.32.0.1
Last usable
63.39.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 3F200000 · Integer 1059061760 to 1059586047
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
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00111111.00100000.00000000.0000000063.32.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network00111111.00100000.00000000.0000000063.32.0.0
Broadcast00111111.00100111.11111111.1111111163.39.255.255
Split into smaller subnets/24
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

63.32.0.0/13 makes 2,048 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
163.32.0.0/2463.32.0.1 to 63.32.0.25463.32.0.255254
263.32.1.0/2463.32.1.1 to 63.32.1.25463.32.1.255254
363.32.2.0/2463.32.2.1 to 63.32.2.25463.32.2.255254
463.32.3.0/2463.32.3.1 to 63.32.3.25463.32.3.255254
563.32.4.0/2463.32.4.1 to 63.32.4.25463.32.4.255254
663.32.5.0/2463.32.5.1 to 63.32.5.25463.32.5.255254
763.32.6.0/2463.32.6.1 to 63.32.6.25463.32.6.255254
863.32.7.0/2463.32.7.1 to 63.32.7.25463.32.7.255254
963.32.8.0/2463.32.8.1 to 63.32.8.25463.32.8.255254
1063.32.9.0/2463.32.9.1 to 63.32.9.25463.32.9.255254
1163.32.10.0/2463.32.10.1 to 63.32.10.25463.32.10.255254
1263.32.11.0/2463.32.11.1 to 63.32.11.25463.32.11.255254
1363.32.12.0/2463.32.12.1 to 63.32.12.25463.32.12.255254
1463.32.13.0/2463.32.13.1 to 63.32.13.25463.32.13.255254
1563.32.14.0/2463.32.14.1 to 63.32.14.25463.32.14.255254
1663.32.15.0/2463.32.15.1 to 63.32.15.25463.32.15.255254
1763.32.16.0/2463.32.16.1 to 63.32.16.25463.32.16.255254
1863.32.17.0/2463.32.17.1 to 63.32.17.25463.32.17.255254
1963.32.18.0/2463.32.18.1 to 63.32.18.25463.32.18.255254
2063.32.19.0/2463.32.19.1 to 63.32.19.25463.32.19.255254
2163.32.20.0/2463.32.20.1 to 63.32.20.25463.32.20.255254
2263.32.21.0/2463.32.21.1 to 63.32.21.25463.32.21.255254
2363.32.22.0/2463.32.22.1 to 63.32.22.25463.32.22.255254
2463.32.23.0/2463.32.23.1 to 63.32.23.25463.32.23.255254
2563.32.24.0/2463.32.24.1 to 63.32.24.25463.32.24.255254
2663.32.25.0/2463.32.25.1 to 63.32.25.25463.32.25.255254
2763.32.26.0/2463.32.26.1 to 63.32.26.25463.32.26.255254
2863.32.27.0/2463.32.27.1 to 63.32.27.25463.32.27.255254
2963.32.28.0/2463.32.28.1 to 63.32.28.25463.32.28.255254
3063.32.29.0/2463.32.29.1 to 63.32.29.25463.32.29.255254
3163.32.30.0/2463.32.30.1 to 63.32.30.25463.32.30.255254
3263.32.31.0/2463.32.31.1 to 63.32.31.25463.32.31.255254
3363.32.32.0/2463.32.32.1 to 63.32.32.25463.32.32.255254
3463.32.33.0/2463.32.33.1 to 63.32.33.25463.32.33.255254
3563.32.34.0/2463.32.34.1 to 63.32.34.25463.32.34.255254
3663.32.35.0/2463.32.35.1 to 63.32.35.25463.32.35.255254
3763.32.36.0/2463.32.36.1 to 63.32.36.25463.32.36.255254
3863.32.37.0/2463.32.37.1 to 63.32.37.25463.32.37.255254
3963.32.38.0/2463.32.38.1 to 63.32.38.25463.32.38.255254
4063.32.39.0/2463.32.39.1 to 63.32.39.25463.32.39.255254
4163.32.40.0/2463.32.40.1 to 63.32.40.25463.32.40.255254
4263.32.41.0/2463.32.41.1 to 63.32.41.25463.32.41.255254
4363.32.42.0/2463.32.42.1 to 63.32.42.25463.32.42.255254
4463.32.43.0/2463.32.43.1 to 63.32.43.25463.32.43.255254
4563.32.44.0/2463.32.44.1 to 63.32.44.25463.32.44.255254
4663.32.45.0/2463.32.45.1 to 63.32.45.25463.32.45.255254
4763.32.46.0/2463.32.46.1 to 63.32.46.25463.32.46.255254
4863.32.47.0/2463.32.47.1 to 63.32.47.25463.32.47.255254
4963.32.48.0/2463.32.48.1 to 63.32.48.25463.32.48.255254
5063.32.49.0/2463.32.49.1 to 63.32.49.25463.32.49.255254
5163.32.50.0/2463.32.50.1 to 63.32.50.25463.32.50.255254
5263.32.51.0/2463.32.51.1 to 63.32.51.25463.32.51.255254
5363.32.52.0/2463.32.52.1 to 63.32.52.25463.32.52.255254
5463.32.53.0/2463.32.53.1 to 63.32.53.25463.32.53.255254
5563.32.54.0/2463.32.54.1 to 63.32.54.25463.32.54.255254
5663.32.55.0/2463.32.55.1 to 63.32.55.25463.32.55.255254
5763.32.56.0/2463.32.56.1 to 63.32.56.25463.32.56.255254
5863.32.57.0/2463.32.57.1 to 63.32.57.25463.32.57.255254
5963.32.58.0/2463.32.58.1 to 63.32.58.25463.32.58.255254
6063.32.59.0/2463.32.59.1 to 63.32.59.25463.32.59.255254
6163.32.60.0/2463.32.60.1 to 63.32.60.25463.32.60.255254
6263.32.61.0/2463.32.61.1 to 63.32.61.25463.32.61.255254
6363.32.62.0/2463.32.62.1 to 63.32.62.25463.32.62.255254
6463.32.63.0/2463.32.63.1 to 63.32.63.25463.32.63.255254
6563.32.64.0/2463.32.64.1 to 63.32.64.25463.32.64.255254
6663.32.65.0/2463.32.65.1 to 63.32.65.25463.32.65.255254
6763.32.66.0/2463.32.66.1 to 63.32.66.25463.32.66.255254
6863.32.67.0/2463.32.67.1 to 63.32.67.25463.32.67.255254
6963.32.68.0/2463.32.68.1 to 63.32.68.25463.32.68.255254
7063.32.69.0/2463.32.69.1 to 63.32.69.25463.32.69.255254
7163.32.70.0/2463.32.70.1 to 63.32.70.25463.32.70.255254
7263.32.71.0/2463.32.71.1 to 63.32.71.25463.32.71.255254
7363.32.72.0/2463.32.72.1 to 63.32.72.25463.32.72.255254
7463.32.73.0/2463.32.73.1 to 63.32.73.25463.32.73.255254
7563.32.74.0/2463.32.74.1 to 63.32.74.25463.32.74.255254
7663.32.75.0/2463.32.75.1 to 63.32.75.25463.32.75.255254
7763.32.76.0/2463.32.76.1 to 63.32.76.25463.32.76.255254
7863.32.77.0/2463.32.77.1 to 63.32.77.25463.32.77.255254
7963.32.78.0/2463.32.78.1 to 63.32.78.25463.32.78.255254
8063.32.79.0/2463.32.79.1 to 63.32.79.25463.32.79.255254
8163.32.80.0/2463.32.80.1 to 63.32.80.25463.32.80.255254
8263.32.81.0/2463.32.81.1 to 63.32.81.25463.32.81.255254
8363.32.82.0/2463.32.82.1 to 63.32.82.25463.32.82.255254
8463.32.83.0/2463.32.83.1 to 63.32.83.25463.32.83.255254
8563.32.84.0/2463.32.84.1 to 63.32.84.25463.32.84.255254
8663.32.85.0/2463.32.85.1 to 63.32.85.25463.32.85.255254
8763.32.86.0/2463.32.86.1 to 63.32.86.25463.32.86.255254
8863.32.87.0/2463.32.87.1 to 63.32.87.25463.32.87.255254
8963.32.88.0/2463.32.88.1 to 63.32.88.25463.32.88.255254
9063.32.89.0/2463.32.89.1 to 63.32.89.25463.32.89.255254
9163.32.90.0/2463.32.90.1 to 63.32.90.25463.32.90.255254
9263.32.91.0/2463.32.91.1 to 63.32.91.25463.32.91.255254
9363.32.92.0/2463.32.92.1 to 63.32.92.25463.32.92.255254
9463.32.93.0/2463.32.93.1 to 63.32.93.25463.32.93.255254
9563.32.94.0/2463.32.94.1 to 63.32.94.25463.32.94.255254
9663.32.95.0/2463.32.95.1 to 63.32.95.25463.32.95.255254
9763.32.96.0/2463.32.96.1 to 63.32.96.25463.32.96.255254
9863.32.97.0/2463.32.97.1 to 63.32.97.25463.32.97.255254
9963.32.98.0/2463.32.98.1 to 63.32.98.25463.32.98.255254
10063.32.99.0/2463.32.99.1 to 63.32.99.25463.32.99.255254
10163.32.100.0/2463.32.100.1 to 63.32.100.25463.32.100.255254
10263.32.101.0/2463.32.101.1 to 63.32.101.25463.32.101.255254
10363.32.102.0/2463.32.102.1 to 63.32.102.25463.32.102.255254
10463.32.103.0/2463.32.103.1 to 63.32.103.25463.32.103.255254
10563.32.104.0/2463.32.104.1 to 63.32.104.25463.32.104.255254
10663.32.105.0/2463.32.105.1 to 63.32.105.25463.32.105.255254
10763.32.106.0/2463.32.106.1 to 63.32.106.25463.32.106.255254
10863.32.107.0/2463.32.107.1 to 63.32.107.25463.32.107.255254
10963.32.108.0/2463.32.108.1 to 63.32.108.25463.32.108.255254
11063.32.109.0/2463.32.109.1 to 63.32.109.25463.32.109.255254
11163.32.110.0/2463.32.110.1 to 63.32.110.25463.32.110.255254
11263.32.111.0/2463.32.111.1 to 63.32.111.25463.32.111.255254
11363.32.112.0/2463.32.112.1 to 63.32.112.25463.32.112.255254
11463.32.113.0/2463.32.113.1 to 63.32.113.25463.32.113.255254
11563.32.114.0/2463.32.114.1 to 63.32.114.25463.32.114.255254
11663.32.115.0/2463.32.115.1 to 63.32.115.25463.32.115.255254
11763.32.116.0/2463.32.116.1 to 63.32.116.25463.32.116.255254
11863.32.117.0/2463.32.117.1 to 63.32.117.25463.32.117.255254
11963.32.118.0/2463.32.118.1 to 63.32.118.25463.32.118.255254
12063.32.119.0/2463.32.119.1 to 63.32.119.25463.32.119.255254
12163.32.120.0/2463.32.120.1 to 63.32.120.25463.32.120.255254
12263.32.121.0/2463.32.121.1 to 63.32.121.25463.32.121.255254
12363.32.122.0/2463.32.122.1 to 63.32.122.25463.32.122.255254
12463.32.123.0/2463.32.123.1 to 63.32.123.25463.32.123.255254
12563.32.124.0/2463.32.124.1 to 63.32.124.25463.32.124.255254
12663.32.125.0/2463.32.125.1 to 63.32.125.25463.32.125.255254
12763.32.126.0/2463.32.126.1 to 63.32.126.25463.32.126.255254
12863.32.127.0/2463.32.127.1 to 63.32.127.25463.32.127.255254
12963.32.128.0/2463.32.128.1 to 63.32.128.25463.32.128.255254
13063.32.129.0/2463.32.129.1 to 63.32.129.25463.32.129.255254
13163.32.130.0/2463.32.130.1 to 63.32.130.25463.32.130.255254
13263.32.131.0/2463.32.131.1 to 63.32.131.25463.32.131.255254
13363.32.132.0/2463.32.132.1 to 63.32.132.25463.32.132.255254
13463.32.133.0/2463.32.133.1 to 63.32.133.25463.32.133.255254
13563.32.134.0/2463.32.134.1 to 63.32.134.25463.32.134.255254
13663.32.135.0/2463.32.135.1 to 63.32.135.25463.32.135.255254
13763.32.136.0/2463.32.136.1 to 63.32.136.25463.32.136.255254
13863.32.137.0/2463.32.137.1 to 63.32.137.25463.32.137.255254
13963.32.138.0/2463.32.138.1 to 63.32.138.25463.32.138.255254
14063.32.139.0/2463.32.139.1 to 63.32.139.25463.32.139.255254
14163.32.140.0/2463.32.140.1 to 63.32.140.25463.32.140.255254
14263.32.141.0/2463.32.141.1 to 63.32.141.25463.32.141.255254
14363.32.142.0/2463.32.142.1 to 63.32.142.25463.32.142.255254
14463.32.143.0/2463.32.143.1 to 63.32.143.25463.32.143.255254
14563.32.144.0/2463.32.144.1 to 63.32.144.25463.32.144.255254
14663.32.145.0/2463.32.145.1 to 63.32.145.25463.32.145.255254
14763.32.146.0/2463.32.146.1 to 63.32.146.25463.32.146.255254
14863.32.147.0/2463.32.147.1 to 63.32.147.25463.32.147.255254
14963.32.148.0/2463.32.148.1 to 63.32.148.25463.32.148.255254
15063.32.149.0/2463.32.149.1 to 63.32.149.25463.32.149.255254
15163.32.150.0/2463.32.150.1 to 63.32.150.25463.32.150.255254
15263.32.151.0/2463.32.151.1 to 63.32.151.25463.32.151.255254
15363.32.152.0/2463.32.152.1 to 63.32.152.25463.32.152.255254
15463.32.153.0/2463.32.153.1 to 63.32.153.25463.32.153.255254
15563.32.154.0/2463.32.154.1 to 63.32.154.25463.32.154.255254
15663.32.155.0/2463.32.155.1 to 63.32.155.25463.32.155.255254
15763.32.156.0/2463.32.156.1 to 63.32.156.25463.32.156.255254
15863.32.157.0/2463.32.157.1 to 63.32.157.25463.32.157.255254
15963.32.158.0/2463.32.158.1 to 63.32.158.25463.32.158.255254
16063.32.159.0/2463.32.159.1 to 63.32.159.25463.32.159.255254
16163.32.160.0/2463.32.160.1 to 63.32.160.25463.32.160.255254
16263.32.161.0/2463.32.161.1 to 63.32.161.25463.32.161.255254
16363.32.162.0/2463.32.162.1 to 63.32.162.25463.32.162.255254
16463.32.163.0/2463.32.163.1 to 63.32.163.25463.32.163.255254
16563.32.164.0/2463.32.164.1 to 63.32.164.25463.32.164.255254
16663.32.165.0/2463.32.165.1 to 63.32.165.25463.32.165.255254
16763.32.166.0/2463.32.166.1 to 63.32.166.25463.32.166.255254
16863.32.167.0/2463.32.167.1 to 63.32.167.25463.32.167.255254
16963.32.168.0/2463.32.168.1 to 63.32.168.25463.32.168.255254
17063.32.169.0/2463.32.169.1 to 63.32.169.25463.32.169.255254
17163.32.170.0/2463.32.170.1 to 63.32.170.25463.32.170.255254
17263.32.171.0/2463.32.171.1 to 63.32.171.25463.32.171.255254
17363.32.172.0/2463.32.172.1 to 63.32.172.25463.32.172.255254
17463.32.173.0/2463.32.173.1 to 63.32.173.25463.32.173.255254
17563.32.174.0/2463.32.174.1 to 63.32.174.25463.32.174.255254
17663.32.175.0/2463.32.175.1 to 63.32.175.25463.32.175.255254
17763.32.176.0/2463.32.176.1 to 63.32.176.25463.32.176.255254
17863.32.177.0/2463.32.177.1 to 63.32.177.25463.32.177.255254
17963.32.178.0/2463.32.178.1 to 63.32.178.25463.32.178.255254
18063.32.179.0/2463.32.179.1 to 63.32.179.25463.32.179.255254
18163.32.180.0/2463.32.180.1 to 63.32.180.25463.32.180.255254
18263.32.181.0/2463.32.181.1 to 63.32.181.25463.32.181.255254
18363.32.182.0/2463.32.182.1 to 63.32.182.25463.32.182.255254
18463.32.183.0/2463.32.183.1 to 63.32.183.25463.32.183.255254
18563.32.184.0/2463.32.184.1 to 63.32.184.25463.32.184.255254
18663.32.185.0/2463.32.185.1 to 63.32.185.25463.32.185.255254
18763.32.186.0/2463.32.186.1 to 63.32.186.25463.32.186.255254
18863.32.187.0/2463.32.187.1 to 63.32.187.25463.32.187.255254
18963.32.188.0/2463.32.188.1 to 63.32.188.25463.32.188.255254
19063.32.189.0/2463.32.189.1 to 63.32.189.25463.32.189.255254
19163.32.190.0/2463.32.190.1 to 63.32.190.25463.32.190.255254
19263.32.191.0/2463.32.191.1 to 63.32.191.25463.32.191.255254
19363.32.192.0/2463.32.192.1 to 63.32.192.25463.32.192.255254
19463.32.193.0/2463.32.193.1 to 63.32.193.25463.32.193.255254
19563.32.194.0/2463.32.194.1 to 63.32.194.25463.32.194.255254
19663.32.195.0/2463.32.195.1 to 63.32.195.25463.32.195.255254
19763.32.196.0/2463.32.196.1 to 63.32.196.25463.32.196.255254
19863.32.197.0/2463.32.197.1 to 63.32.197.25463.32.197.255254
19963.32.198.0/2463.32.198.1 to 63.32.198.25463.32.198.255254
20063.32.199.0/2463.32.199.1 to 63.32.199.25463.32.199.255254
20163.32.200.0/2463.32.200.1 to 63.32.200.25463.32.200.255254
20263.32.201.0/2463.32.201.1 to 63.32.201.25463.32.201.255254
20363.32.202.0/2463.32.202.1 to 63.32.202.25463.32.202.255254
20463.32.203.0/2463.32.203.1 to 63.32.203.25463.32.203.255254
20563.32.204.0/2463.32.204.1 to 63.32.204.25463.32.204.255254
20663.32.205.0/2463.32.205.1 to 63.32.205.25463.32.205.255254
20763.32.206.0/2463.32.206.1 to 63.32.206.25463.32.206.255254
20863.32.207.0/2463.32.207.1 to 63.32.207.25463.32.207.255254
20963.32.208.0/2463.32.208.1 to 63.32.208.25463.32.208.255254
21063.32.209.0/2463.32.209.1 to 63.32.209.25463.32.209.255254
21163.32.210.0/2463.32.210.1 to 63.32.210.25463.32.210.255254
21263.32.211.0/2463.32.211.1 to 63.32.211.25463.32.211.255254
21363.32.212.0/2463.32.212.1 to 63.32.212.25463.32.212.255254
21463.32.213.0/2463.32.213.1 to 63.32.213.25463.32.213.255254
21563.32.214.0/2463.32.214.1 to 63.32.214.25463.32.214.255254
21663.32.215.0/2463.32.215.1 to 63.32.215.25463.32.215.255254
21763.32.216.0/2463.32.216.1 to 63.32.216.25463.32.216.255254
21863.32.217.0/2463.32.217.1 to 63.32.217.25463.32.217.255254
21963.32.218.0/2463.32.218.1 to 63.32.218.25463.32.218.255254
22063.32.219.0/2463.32.219.1 to 63.32.219.25463.32.219.255254
22163.32.220.0/2463.32.220.1 to 63.32.220.25463.32.220.255254
22263.32.221.0/2463.32.221.1 to 63.32.221.25463.32.221.255254
22363.32.222.0/2463.32.222.1 to 63.32.222.25463.32.222.255254
22463.32.223.0/2463.32.223.1 to 63.32.223.25463.32.223.255254
22563.32.224.0/2463.32.224.1 to 63.32.224.25463.32.224.255254
22663.32.225.0/2463.32.225.1 to 63.32.225.25463.32.225.255254
22763.32.226.0/2463.32.226.1 to 63.32.226.25463.32.226.255254
22863.32.227.0/2463.32.227.1 to 63.32.227.25463.32.227.255254
22963.32.228.0/2463.32.228.1 to 63.32.228.25463.32.228.255254
23063.32.229.0/2463.32.229.1 to 63.32.229.25463.32.229.255254
23163.32.230.0/2463.32.230.1 to 63.32.230.25463.32.230.255254
23263.32.231.0/2463.32.231.1 to 63.32.231.25463.32.231.255254
23363.32.232.0/2463.32.232.1 to 63.32.232.25463.32.232.255254
23463.32.233.0/2463.32.233.1 to 63.32.233.25463.32.233.255254
23563.32.234.0/2463.32.234.1 to 63.32.234.25463.32.234.255254
23663.32.235.0/2463.32.235.1 to 63.32.235.25463.32.235.255254
23763.32.236.0/2463.32.236.1 to 63.32.236.25463.32.236.255254
23863.32.237.0/2463.32.237.1 to 63.32.237.25463.32.237.255254
23963.32.238.0/2463.32.238.1 to 63.32.238.25463.32.238.255254
24063.32.239.0/2463.32.239.1 to 63.32.239.25463.32.239.255254
24163.32.240.0/2463.32.240.1 to 63.32.240.25463.32.240.255254
24263.32.241.0/2463.32.241.1 to 63.32.241.25463.32.241.255254
24363.32.242.0/2463.32.242.1 to 63.32.242.25463.32.242.255254
24463.32.243.0/2463.32.243.1 to 63.32.243.25463.32.243.255254
24563.32.244.0/2463.32.244.1 to 63.32.244.25463.32.244.255254
24663.32.245.0/2463.32.245.1 to 63.32.245.25463.32.245.255254
24763.32.246.0/2463.32.246.1 to 63.32.246.25463.32.246.255254
24863.32.247.0/2463.32.247.1 to 63.32.247.25463.32.247.255254
24963.32.248.0/2463.32.248.1 to 63.32.248.25463.32.248.255254
25063.32.249.0/2463.32.249.1 to 63.32.249.25463.32.249.255254
25163.32.250.0/2463.32.250.1 to 63.32.250.25463.32.250.255254
25263.32.251.0/2463.32.251.1 to 63.32.251.25463.32.251.255254
25363.32.252.0/2463.32.252.1 to 63.32.252.25463.32.252.255254
25463.32.253.0/2463.32.253.1 to 63.32.253.25463.32.253.255254
25563.32.254.0/2463.32.254.1 to 63.32.254.25463.32.254.255254
25663.32.255.0/2463.32.255.1 to 63.32.255.25463.32.255.255254

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.