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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.

Network80.53.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
80.53.0.0
Broadcast address
80.53.255.255
First usable
80.53.0.1
Last usable
80.53.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 50350000 · Integer 1345650688 to 1345716223
Reverse DNS zone
53.80.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010000.00110101..00000000.0000000080.53.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01010000.00110101..00000000.0000000080.53.0.0
Broadcast01010000.00110101..11111111.1111111180.53.255.255
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

80.53.0.0/16 makes 256 subnets of /24.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
180.53.0.0/2480.53.0.1 to 80.53.0.25480.53.0.255254
280.53.1.0/2480.53.1.1 to 80.53.1.25480.53.1.255254
380.53.2.0/2480.53.2.1 to 80.53.2.25480.53.2.255254
480.53.3.0/2480.53.3.1 to 80.53.3.25480.53.3.255254
580.53.4.0/2480.53.4.1 to 80.53.4.25480.53.4.255254
680.53.5.0/2480.53.5.1 to 80.53.5.25480.53.5.255254
780.53.6.0/2480.53.6.1 to 80.53.6.25480.53.6.255254
880.53.7.0/2480.53.7.1 to 80.53.7.25480.53.7.255254
980.53.8.0/2480.53.8.1 to 80.53.8.25480.53.8.255254
1080.53.9.0/2480.53.9.1 to 80.53.9.25480.53.9.255254
1180.53.10.0/2480.53.10.1 to 80.53.10.25480.53.10.255254
1280.53.11.0/2480.53.11.1 to 80.53.11.25480.53.11.255254
1380.53.12.0/2480.53.12.1 to 80.53.12.25480.53.12.255254
1480.53.13.0/2480.53.13.1 to 80.53.13.25480.53.13.255254
1580.53.14.0/2480.53.14.1 to 80.53.14.25480.53.14.255254
1680.53.15.0/2480.53.15.1 to 80.53.15.25480.53.15.255254
1780.53.16.0/2480.53.16.1 to 80.53.16.25480.53.16.255254
1880.53.17.0/2480.53.17.1 to 80.53.17.25480.53.17.255254
1980.53.18.0/2480.53.18.1 to 80.53.18.25480.53.18.255254
2080.53.19.0/2480.53.19.1 to 80.53.19.25480.53.19.255254
2180.53.20.0/2480.53.20.1 to 80.53.20.25480.53.20.255254
2280.53.21.0/2480.53.21.1 to 80.53.21.25480.53.21.255254
2380.53.22.0/2480.53.22.1 to 80.53.22.25480.53.22.255254
2480.53.23.0/2480.53.23.1 to 80.53.23.25480.53.23.255254
2580.53.24.0/2480.53.24.1 to 80.53.24.25480.53.24.255254
2680.53.25.0/2480.53.25.1 to 80.53.25.25480.53.25.255254
2780.53.26.0/2480.53.26.1 to 80.53.26.25480.53.26.255254
2880.53.27.0/2480.53.27.1 to 80.53.27.25480.53.27.255254
2980.53.28.0/2480.53.28.1 to 80.53.28.25480.53.28.255254
3080.53.29.0/2480.53.29.1 to 80.53.29.25480.53.29.255254
3180.53.30.0/2480.53.30.1 to 80.53.30.25480.53.30.255254
3280.53.31.0/2480.53.31.1 to 80.53.31.25480.53.31.255254
3380.53.32.0/2480.53.32.1 to 80.53.32.25480.53.32.255254
3480.53.33.0/2480.53.33.1 to 80.53.33.25480.53.33.255254
3580.53.34.0/2480.53.34.1 to 80.53.34.25480.53.34.255254
3680.53.35.0/2480.53.35.1 to 80.53.35.25480.53.35.255254
3780.53.36.0/2480.53.36.1 to 80.53.36.25480.53.36.255254
3880.53.37.0/2480.53.37.1 to 80.53.37.25480.53.37.255254
3980.53.38.0/2480.53.38.1 to 80.53.38.25480.53.38.255254
4080.53.39.0/2480.53.39.1 to 80.53.39.25480.53.39.255254
4180.53.40.0/2480.53.40.1 to 80.53.40.25480.53.40.255254
4280.53.41.0/2480.53.41.1 to 80.53.41.25480.53.41.255254
4380.53.42.0/2480.53.42.1 to 80.53.42.25480.53.42.255254
4480.53.43.0/2480.53.43.1 to 80.53.43.25480.53.43.255254
4580.53.44.0/2480.53.44.1 to 80.53.44.25480.53.44.255254
4680.53.45.0/2480.53.45.1 to 80.53.45.25480.53.45.255254
4780.53.46.0/2480.53.46.1 to 80.53.46.25480.53.46.255254
4880.53.47.0/2480.53.47.1 to 80.53.47.25480.53.47.255254
4980.53.48.0/2480.53.48.1 to 80.53.48.25480.53.48.255254
5080.53.49.0/2480.53.49.1 to 80.53.49.25480.53.49.255254
5180.53.50.0/2480.53.50.1 to 80.53.50.25480.53.50.255254
5280.53.51.0/2480.53.51.1 to 80.53.51.25480.53.51.255254
5380.53.52.0/2480.53.52.1 to 80.53.52.25480.53.52.255254
5480.53.53.0/2480.53.53.1 to 80.53.53.25480.53.53.255254
5580.53.54.0/2480.53.54.1 to 80.53.54.25480.53.54.255254
5680.53.55.0/2480.53.55.1 to 80.53.55.25480.53.55.255254
5780.53.56.0/2480.53.56.1 to 80.53.56.25480.53.56.255254
5880.53.57.0/2480.53.57.1 to 80.53.57.25480.53.57.255254
5980.53.58.0/2480.53.58.1 to 80.53.58.25480.53.58.255254
6080.53.59.0/2480.53.59.1 to 80.53.59.25480.53.59.255254
6180.53.60.0/2480.53.60.1 to 80.53.60.25480.53.60.255254
6280.53.61.0/2480.53.61.1 to 80.53.61.25480.53.61.255254
6380.53.62.0/2480.53.62.1 to 80.53.62.25480.53.62.255254
6480.53.63.0/2480.53.63.1 to 80.53.63.25480.53.63.255254
6580.53.64.0/2480.53.64.1 to 80.53.64.25480.53.64.255254
6680.53.65.0/2480.53.65.1 to 80.53.65.25480.53.65.255254
6780.53.66.0/2480.53.66.1 to 80.53.66.25480.53.66.255254
6880.53.67.0/2480.53.67.1 to 80.53.67.25480.53.67.255254
6980.53.68.0/2480.53.68.1 to 80.53.68.25480.53.68.255254
7080.53.69.0/2480.53.69.1 to 80.53.69.25480.53.69.255254
7180.53.70.0/2480.53.70.1 to 80.53.70.25480.53.70.255254
7280.53.71.0/2480.53.71.1 to 80.53.71.25480.53.71.255254
7380.53.72.0/2480.53.72.1 to 80.53.72.25480.53.72.255254
7480.53.73.0/2480.53.73.1 to 80.53.73.25480.53.73.255254
7580.53.74.0/2480.53.74.1 to 80.53.74.25480.53.74.255254
7680.53.75.0/2480.53.75.1 to 80.53.75.25480.53.75.255254
7780.53.76.0/2480.53.76.1 to 80.53.76.25480.53.76.255254
7880.53.77.0/2480.53.77.1 to 80.53.77.25480.53.77.255254
7980.53.78.0/2480.53.78.1 to 80.53.78.25480.53.78.255254
8080.53.79.0/2480.53.79.1 to 80.53.79.25480.53.79.255254
8180.53.80.0/2480.53.80.1 to 80.53.80.25480.53.80.255254
8280.53.81.0/2480.53.81.1 to 80.53.81.25480.53.81.255254
8380.53.82.0/2480.53.82.1 to 80.53.82.25480.53.82.255254
8480.53.83.0/2480.53.83.1 to 80.53.83.25480.53.83.255254
8580.53.84.0/2480.53.84.1 to 80.53.84.25480.53.84.255254
8680.53.85.0/2480.53.85.1 to 80.53.85.25480.53.85.255254
8780.53.86.0/2480.53.86.1 to 80.53.86.25480.53.86.255254
8880.53.87.0/2480.53.87.1 to 80.53.87.25480.53.87.255254
8980.53.88.0/2480.53.88.1 to 80.53.88.25480.53.88.255254
9080.53.89.0/2480.53.89.1 to 80.53.89.25480.53.89.255254
9180.53.90.0/2480.53.90.1 to 80.53.90.25480.53.90.255254
9280.53.91.0/2480.53.91.1 to 80.53.91.25480.53.91.255254
9380.53.92.0/2480.53.92.1 to 80.53.92.25480.53.92.255254
9480.53.93.0/2480.53.93.1 to 80.53.93.25480.53.93.255254
9580.53.94.0/2480.53.94.1 to 80.53.94.25480.53.94.255254
9680.53.95.0/2480.53.95.1 to 80.53.95.25480.53.95.255254
9780.53.96.0/2480.53.96.1 to 80.53.96.25480.53.96.255254
9880.53.97.0/2480.53.97.1 to 80.53.97.25480.53.97.255254
9980.53.98.0/2480.53.98.1 to 80.53.98.25480.53.98.255254
10080.53.99.0/2480.53.99.1 to 80.53.99.25480.53.99.255254
10180.53.100.0/2480.53.100.1 to 80.53.100.25480.53.100.255254
10280.53.101.0/2480.53.101.1 to 80.53.101.25480.53.101.255254
10380.53.102.0/2480.53.102.1 to 80.53.102.25480.53.102.255254
10480.53.103.0/2480.53.103.1 to 80.53.103.25480.53.103.255254
10580.53.104.0/2480.53.104.1 to 80.53.104.25480.53.104.255254
10680.53.105.0/2480.53.105.1 to 80.53.105.25480.53.105.255254
10780.53.106.0/2480.53.106.1 to 80.53.106.25480.53.106.255254
10880.53.107.0/2480.53.107.1 to 80.53.107.25480.53.107.255254
10980.53.108.0/2480.53.108.1 to 80.53.108.25480.53.108.255254
11080.53.109.0/2480.53.109.1 to 80.53.109.25480.53.109.255254
11180.53.110.0/2480.53.110.1 to 80.53.110.25480.53.110.255254
11280.53.111.0/2480.53.111.1 to 80.53.111.25480.53.111.255254
11380.53.112.0/2480.53.112.1 to 80.53.112.25480.53.112.255254
11480.53.113.0/2480.53.113.1 to 80.53.113.25480.53.113.255254
11580.53.114.0/2480.53.114.1 to 80.53.114.25480.53.114.255254
11680.53.115.0/2480.53.115.1 to 80.53.115.25480.53.115.255254
11780.53.116.0/2480.53.116.1 to 80.53.116.25480.53.116.255254
11880.53.117.0/2480.53.117.1 to 80.53.117.25480.53.117.255254
11980.53.118.0/2480.53.118.1 to 80.53.118.25480.53.118.255254
12080.53.119.0/2480.53.119.1 to 80.53.119.25480.53.119.255254
12180.53.120.0/2480.53.120.1 to 80.53.120.25480.53.120.255254
12280.53.121.0/2480.53.121.1 to 80.53.121.25480.53.121.255254
12380.53.122.0/2480.53.122.1 to 80.53.122.25480.53.122.255254
12480.53.123.0/2480.53.123.1 to 80.53.123.25480.53.123.255254
12580.53.124.0/2480.53.124.1 to 80.53.124.25480.53.124.255254
12680.53.125.0/2480.53.125.1 to 80.53.125.25480.53.125.255254
12780.53.126.0/2480.53.126.1 to 80.53.126.25480.53.126.255254
12880.53.127.0/2480.53.127.1 to 80.53.127.25480.53.127.255254
12980.53.128.0/2480.53.128.1 to 80.53.128.25480.53.128.255254
13080.53.129.0/2480.53.129.1 to 80.53.129.25480.53.129.255254
13180.53.130.0/2480.53.130.1 to 80.53.130.25480.53.130.255254
13280.53.131.0/2480.53.131.1 to 80.53.131.25480.53.131.255254
13380.53.132.0/2480.53.132.1 to 80.53.132.25480.53.132.255254
13480.53.133.0/2480.53.133.1 to 80.53.133.25480.53.133.255254
13580.53.134.0/2480.53.134.1 to 80.53.134.25480.53.134.255254
13680.53.135.0/2480.53.135.1 to 80.53.135.25480.53.135.255254
13780.53.136.0/2480.53.136.1 to 80.53.136.25480.53.136.255254
13880.53.137.0/2480.53.137.1 to 80.53.137.25480.53.137.255254
13980.53.138.0/2480.53.138.1 to 80.53.138.25480.53.138.255254
14080.53.139.0/2480.53.139.1 to 80.53.139.25480.53.139.255254
14180.53.140.0/2480.53.140.1 to 80.53.140.25480.53.140.255254
14280.53.141.0/2480.53.141.1 to 80.53.141.25480.53.141.255254
14380.53.142.0/2480.53.142.1 to 80.53.142.25480.53.142.255254
14480.53.143.0/2480.53.143.1 to 80.53.143.25480.53.143.255254
14580.53.144.0/2480.53.144.1 to 80.53.144.25480.53.144.255254
14680.53.145.0/2480.53.145.1 to 80.53.145.25480.53.145.255254
14780.53.146.0/2480.53.146.1 to 80.53.146.25480.53.146.255254
14880.53.147.0/2480.53.147.1 to 80.53.147.25480.53.147.255254
14980.53.148.0/2480.53.148.1 to 80.53.148.25480.53.148.255254
15080.53.149.0/2480.53.149.1 to 80.53.149.25480.53.149.255254
15180.53.150.0/2480.53.150.1 to 80.53.150.25480.53.150.255254
15280.53.151.0/2480.53.151.1 to 80.53.151.25480.53.151.255254
15380.53.152.0/2480.53.152.1 to 80.53.152.25480.53.152.255254
15480.53.153.0/2480.53.153.1 to 80.53.153.25480.53.153.255254
15580.53.154.0/2480.53.154.1 to 80.53.154.25480.53.154.255254
15680.53.155.0/2480.53.155.1 to 80.53.155.25480.53.155.255254
15780.53.156.0/2480.53.156.1 to 80.53.156.25480.53.156.255254
15880.53.157.0/2480.53.157.1 to 80.53.157.25480.53.157.255254
15980.53.158.0/2480.53.158.1 to 80.53.158.25480.53.158.255254
16080.53.159.0/2480.53.159.1 to 80.53.159.25480.53.159.255254
16180.53.160.0/2480.53.160.1 to 80.53.160.25480.53.160.255254
16280.53.161.0/2480.53.161.1 to 80.53.161.25480.53.161.255254
16380.53.162.0/2480.53.162.1 to 80.53.162.25480.53.162.255254
16480.53.163.0/2480.53.163.1 to 80.53.163.25480.53.163.255254
16580.53.164.0/2480.53.164.1 to 80.53.164.25480.53.164.255254
16680.53.165.0/2480.53.165.1 to 80.53.165.25480.53.165.255254
16780.53.166.0/2480.53.166.1 to 80.53.166.25480.53.166.255254
16880.53.167.0/2480.53.167.1 to 80.53.167.25480.53.167.255254
16980.53.168.0/2480.53.168.1 to 80.53.168.25480.53.168.255254
17080.53.169.0/2480.53.169.1 to 80.53.169.25480.53.169.255254
17180.53.170.0/2480.53.170.1 to 80.53.170.25480.53.170.255254
17280.53.171.0/2480.53.171.1 to 80.53.171.25480.53.171.255254
17380.53.172.0/2480.53.172.1 to 80.53.172.25480.53.172.255254
17480.53.173.0/2480.53.173.1 to 80.53.173.25480.53.173.255254
17580.53.174.0/2480.53.174.1 to 80.53.174.25480.53.174.255254
17680.53.175.0/2480.53.175.1 to 80.53.175.25480.53.175.255254
17780.53.176.0/2480.53.176.1 to 80.53.176.25480.53.176.255254
17880.53.177.0/2480.53.177.1 to 80.53.177.25480.53.177.255254
17980.53.178.0/2480.53.178.1 to 80.53.178.25480.53.178.255254
18080.53.179.0/2480.53.179.1 to 80.53.179.25480.53.179.255254
18180.53.180.0/2480.53.180.1 to 80.53.180.25480.53.180.255254
18280.53.181.0/2480.53.181.1 to 80.53.181.25480.53.181.255254
18380.53.182.0/2480.53.182.1 to 80.53.182.25480.53.182.255254
18480.53.183.0/2480.53.183.1 to 80.53.183.25480.53.183.255254
18580.53.184.0/2480.53.184.1 to 80.53.184.25480.53.184.255254
18680.53.185.0/2480.53.185.1 to 80.53.185.25480.53.185.255254
18780.53.186.0/2480.53.186.1 to 80.53.186.25480.53.186.255254
18880.53.187.0/2480.53.187.1 to 80.53.187.25480.53.187.255254
18980.53.188.0/2480.53.188.1 to 80.53.188.25480.53.188.255254
19080.53.189.0/2480.53.189.1 to 80.53.189.25480.53.189.255254
19180.53.190.0/2480.53.190.1 to 80.53.190.25480.53.190.255254
19280.53.191.0/2480.53.191.1 to 80.53.191.25480.53.191.255254
19380.53.192.0/2480.53.192.1 to 80.53.192.25480.53.192.255254
19480.53.193.0/2480.53.193.1 to 80.53.193.25480.53.193.255254
19580.53.194.0/2480.53.194.1 to 80.53.194.25480.53.194.255254
19680.53.195.0/2480.53.195.1 to 80.53.195.25480.53.195.255254
19780.53.196.0/2480.53.196.1 to 80.53.196.25480.53.196.255254
19880.53.197.0/2480.53.197.1 to 80.53.197.25480.53.197.255254
19980.53.198.0/2480.53.198.1 to 80.53.198.25480.53.198.255254
20080.53.199.0/2480.53.199.1 to 80.53.199.25480.53.199.255254
20180.53.200.0/2480.53.200.1 to 80.53.200.25480.53.200.255254
20280.53.201.0/2480.53.201.1 to 80.53.201.25480.53.201.255254
20380.53.202.0/2480.53.202.1 to 80.53.202.25480.53.202.255254
20480.53.203.0/2480.53.203.1 to 80.53.203.25480.53.203.255254
20580.53.204.0/2480.53.204.1 to 80.53.204.25480.53.204.255254
20680.53.205.0/2480.53.205.1 to 80.53.205.25480.53.205.255254
20780.53.206.0/2480.53.206.1 to 80.53.206.25480.53.206.255254
20880.53.207.0/2480.53.207.1 to 80.53.207.25480.53.207.255254
20980.53.208.0/2480.53.208.1 to 80.53.208.25480.53.208.255254
21080.53.209.0/2480.53.209.1 to 80.53.209.25480.53.209.255254
21180.53.210.0/2480.53.210.1 to 80.53.210.25480.53.210.255254
21280.53.211.0/2480.53.211.1 to 80.53.211.25480.53.211.255254
21380.53.212.0/2480.53.212.1 to 80.53.212.25480.53.212.255254
21480.53.213.0/2480.53.213.1 to 80.53.213.25480.53.213.255254
21580.53.214.0/2480.53.214.1 to 80.53.214.25480.53.214.255254
21680.53.215.0/2480.53.215.1 to 80.53.215.25480.53.215.255254
21780.53.216.0/2480.53.216.1 to 80.53.216.25480.53.216.255254
21880.53.217.0/2480.53.217.1 to 80.53.217.25480.53.217.255254
21980.53.218.0/2480.53.218.1 to 80.53.218.25480.53.218.255254
22080.53.219.0/2480.53.219.1 to 80.53.219.25480.53.219.255254
22180.53.220.0/2480.53.220.1 to 80.53.220.25480.53.220.255254
22280.53.221.0/2480.53.221.1 to 80.53.221.25480.53.221.255254
22380.53.222.0/2480.53.222.1 to 80.53.222.25480.53.222.255254
22480.53.223.0/2480.53.223.1 to 80.53.223.25480.53.223.255254
22580.53.224.0/2480.53.224.1 to 80.53.224.25480.53.224.255254
22680.53.225.0/2480.53.225.1 to 80.53.225.25480.53.225.255254
22780.53.226.0/2480.53.226.1 to 80.53.226.25480.53.226.255254
22880.53.227.0/2480.53.227.1 to 80.53.227.25480.53.227.255254
22980.53.228.0/2480.53.228.1 to 80.53.228.25480.53.228.255254
23080.53.229.0/2480.53.229.1 to 80.53.229.25480.53.229.255254
23180.53.230.0/2480.53.230.1 to 80.53.230.25480.53.230.255254
23280.53.231.0/2480.53.231.1 to 80.53.231.25480.53.231.255254
23380.53.232.0/2480.53.232.1 to 80.53.232.25480.53.232.255254
23480.53.233.0/2480.53.233.1 to 80.53.233.25480.53.233.255254
23580.53.234.0/2480.53.234.1 to 80.53.234.25480.53.234.255254
23680.53.235.0/2480.53.235.1 to 80.53.235.25480.53.235.255254
23780.53.236.0/2480.53.236.1 to 80.53.236.25480.53.236.255254
23880.53.237.0/2480.53.237.1 to 80.53.237.25480.53.237.255254
23980.53.238.0/2480.53.238.1 to 80.53.238.25480.53.238.255254
24080.53.239.0/2480.53.239.1 to 80.53.239.25480.53.239.255254
24180.53.240.0/2480.53.240.1 to 80.53.240.25480.53.240.255254
24280.53.241.0/2480.53.241.1 to 80.53.241.25480.53.241.255254
24380.53.242.0/2480.53.242.1 to 80.53.242.25480.53.242.255254
24480.53.243.0/2480.53.243.1 to 80.53.243.25480.53.243.255254
24580.53.244.0/2480.53.244.1 to 80.53.244.25480.53.244.255254
24680.53.245.0/2480.53.245.1 to 80.53.245.25480.53.245.255254
24780.53.246.0/2480.53.246.1 to 80.53.246.25480.53.246.255254
24880.53.247.0/2480.53.247.1 to 80.53.247.25480.53.247.255254
24980.53.248.0/2480.53.248.1 to 80.53.248.25480.53.248.255254
25080.53.249.0/2480.53.249.1 to 80.53.249.25480.53.249.255254
25180.53.250.0/2480.53.250.1 to 80.53.250.25480.53.250.255254
25280.53.251.0/2480.53.251.1 to 80.53.251.25480.53.251.255254
25380.53.252.0/2480.53.252.1 to 80.53.252.25480.53.252.255254
25480.53.253.0/2480.53.253.1 to 80.53.253.25480.53.253.255254
25580.53.254.0/2480.53.254.1 to 80.53.254.25480.53.254.255254
25680.53.255.0/2480.53.255.1 to 80.53.255.25480.53.255.255254

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.