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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.

Network80.78.0.0/15
Usable hosts131,070
Subnet mask255.254.0.0
Addresses131,072
Network address
80.78.0.0
Broadcast address
80.79.255.255
First usable
80.78.0.1
Last usable
80.79.255.254
Usable hosts
131,070 (131,072 less the network and broadcast addresses)
Subnet mask
255.254.0.0
Wildcard mask
0.1.255.255 (Cisco ACLs, OSPF)
Prefix length
/15
Type
Public public
Old class
A (default /8)
As numbers
Hex 504E0000 · Integer 1347289088 to 1347420159
Reverse DNS zones
78.80.in-addr.arpa
79.80.in-addr.arpa
/15 is not on a 8-bit boundary, so it takes 2 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010000.01001110.00000000.0000000080.78.0.0
Subnet mask11111111.11111110.00000000.00000000255.254.0.0
Network01010000.01001110.00000000.0000000080.78.0.0
Broadcast01010000.01001111.11111111.1111111180.79.255.255
Split into smaller subnets/23

80.78.0.0/15 makes 256 subnets of /23.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
180.78.0.0/2380.78.0.1 to 80.78.1.25480.78.1.255510
280.78.2.0/2380.78.2.1 to 80.78.3.25480.78.3.255510
380.78.4.0/2380.78.4.1 to 80.78.5.25480.78.5.255510
480.78.6.0/2380.78.6.1 to 80.78.7.25480.78.7.255510
580.78.8.0/2380.78.8.1 to 80.78.9.25480.78.9.255510
680.78.10.0/2380.78.10.1 to 80.78.11.25480.78.11.255510
780.78.12.0/2380.78.12.1 to 80.78.13.25480.78.13.255510
880.78.14.0/2380.78.14.1 to 80.78.15.25480.78.15.255510
980.78.16.0/2380.78.16.1 to 80.78.17.25480.78.17.255510
1080.78.18.0/2380.78.18.1 to 80.78.19.25480.78.19.255510
1180.78.20.0/2380.78.20.1 to 80.78.21.25480.78.21.255510
1280.78.22.0/2380.78.22.1 to 80.78.23.25480.78.23.255510
1380.78.24.0/2380.78.24.1 to 80.78.25.25480.78.25.255510
1480.78.26.0/2380.78.26.1 to 80.78.27.25480.78.27.255510
1580.78.28.0/2380.78.28.1 to 80.78.29.25480.78.29.255510
1680.78.30.0/2380.78.30.1 to 80.78.31.25480.78.31.255510
1780.78.32.0/2380.78.32.1 to 80.78.33.25480.78.33.255510
1880.78.34.0/2380.78.34.1 to 80.78.35.25480.78.35.255510
1980.78.36.0/2380.78.36.1 to 80.78.37.25480.78.37.255510
2080.78.38.0/2380.78.38.1 to 80.78.39.25480.78.39.255510
2180.78.40.0/2380.78.40.1 to 80.78.41.25480.78.41.255510
2280.78.42.0/2380.78.42.1 to 80.78.43.25480.78.43.255510
2380.78.44.0/2380.78.44.1 to 80.78.45.25480.78.45.255510
2480.78.46.0/2380.78.46.1 to 80.78.47.25480.78.47.255510
2580.78.48.0/2380.78.48.1 to 80.78.49.25480.78.49.255510
2680.78.50.0/2380.78.50.1 to 80.78.51.25480.78.51.255510
2780.78.52.0/2380.78.52.1 to 80.78.53.25480.78.53.255510
2880.78.54.0/2380.78.54.1 to 80.78.55.25480.78.55.255510
2980.78.56.0/2380.78.56.1 to 80.78.57.25480.78.57.255510
3080.78.58.0/2380.78.58.1 to 80.78.59.25480.78.59.255510
3180.78.60.0/2380.78.60.1 to 80.78.61.25480.78.61.255510
3280.78.62.0/2380.78.62.1 to 80.78.63.25480.78.63.255510
3380.78.64.0/2380.78.64.1 to 80.78.65.25480.78.65.255510
3480.78.66.0/2380.78.66.1 to 80.78.67.25480.78.67.255510
3580.78.68.0/2380.78.68.1 to 80.78.69.25480.78.69.255510
3680.78.70.0/2380.78.70.1 to 80.78.71.25480.78.71.255510
3780.78.72.0/2380.78.72.1 to 80.78.73.25480.78.73.255510
3880.78.74.0/2380.78.74.1 to 80.78.75.25480.78.75.255510
3980.78.76.0/2380.78.76.1 to 80.78.77.25480.78.77.255510
4080.78.78.0/2380.78.78.1 to 80.78.79.25480.78.79.255510
4180.78.80.0/2380.78.80.1 to 80.78.81.25480.78.81.255510
4280.78.82.0/2380.78.82.1 to 80.78.83.25480.78.83.255510
4380.78.84.0/2380.78.84.1 to 80.78.85.25480.78.85.255510
4480.78.86.0/2380.78.86.1 to 80.78.87.25480.78.87.255510
4580.78.88.0/2380.78.88.1 to 80.78.89.25480.78.89.255510
4680.78.90.0/2380.78.90.1 to 80.78.91.25480.78.91.255510
4780.78.92.0/2380.78.92.1 to 80.78.93.25480.78.93.255510
4880.78.94.0/2380.78.94.1 to 80.78.95.25480.78.95.255510
4980.78.96.0/2380.78.96.1 to 80.78.97.25480.78.97.255510
5080.78.98.0/2380.78.98.1 to 80.78.99.25480.78.99.255510
5180.78.100.0/2380.78.100.1 to 80.78.101.25480.78.101.255510
5280.78.102.0/2380.78.102.1 to 80.78.103.25480.78.103.255510
5380.78.104.0/2380.78.104.1 to 80.78.105.25480.78.105.255510
5480.78.106.0/2380.78.106.1 to 80.78.107.25480.78.107.255510
5580.78.108.0/2380.78.108.1 to 80.78.109.25480.78.109.255510
5680.78.110.0/2380.78.110.1 to 80.78.111.25480.78.111.255510
5780.78.112.0/2380.78.112.1 to 80.78.113.25480.78.113.255510
5880.78.114.0/2380.78.114.1 to 80.78.115.25480.78.115.255510
5980.78.116.0/2380.78.116.1 to 80.78.117.25480.78.117.255510
6080.78.118.0/2380.78.118.1 to 80.78.119.25480.78.119.255510
6180.78.120.0/2380.78.120.1 to 80.78.121.25480.78.121.255510
6280.78.122.0/2380.78.122.1 to 80.78.123.25480.78.123.255510
6380.78.124.0/2380.78.124.1 to 80.78.125.25480.78.125.255510
6480.78.126.0/2380.78.126.1 to 80.78.127.25480.78.127.255510
6580.78.128.0/2380.78.128.1 to 80.78.129.25480.78.129.255510
6680.78.130.0/2380.78.130.1 to 80.78.131.25480.78.131.255510
6780.78.132.0/2380.78.132.1 to 80.78.133.25480.78.133.255510
6880.78.134.0/2380.78.134.1 to 80.78.135.25480.78.135.255510
6980.78.136.0/2380.78.136.1 to 80.78.137.25480.78.137.255510
7080.78.138.0/2380.78.138.1 to 80.78.139.25480.78.139.255510
7180.78.140.0/2380.78.140.1 to 80.78.141.25480.78.141.255510
7280.78.142.0/2380.78.142.1 to 80.78.143.25480.78.143.255510
7380.78.144.0/2380.78.144.1 to 80.78.145.25480.78.145.255510
7480.78.146.0/2380.78.146.1 to 80.78.147.25480.78.147.255510
7580.78.148.0/2380.78.148.1 to 80.78.149.25480.78.149.255510
7680.78.150.0/2380.78.150.1 to 80.78.151.25480.78.151.255510
7780.78.152.0/2380.78.152.1 to 80.78.153.25480.78.153.255510
7880.78.154.0/2380.78.154.1 to 80.78.155.25480.78.155.255510
7980.78.156.0/2380.78.156.1 to 80.78.157.25480.78.157.255510
8080.78.158.0/2380.78.158.1 to 80.78.159.25480.78.159.255510
8180.78.160.0/2380.78.160.1 to 80.78.161.25480.78.161.255510
8280.78.162.0/2380.78.162.1 to 80.78.163.25480.78.163.255510
8380.78.164.0/2380.78.164.1 to 80.78.165.25480.78.165.255510
8480.78.166.0/2380.78.166.1 to 80.78.167.25480.78.167.255510
8580.78.168.0/2380.78.168.1 to 80.78.169.25480.78.169.255510
8680.78.170.0/2380.78.170.1 to 80.78.171.25480.78.171.255510
8780.78.172.0/2380.78.172.1 to 80.78.173.25480.78.173.255510
8880.78.174.0/2380.78.174.1 to 80.78.175.25480.78.175.255510
8980.78.176.0/2380.78.176.1 to 80.78.177.25480.78.177.255510
9080.78.178.0/2380.78.178.1 to 80.78.179.25480.78.179.255510
9180.78.180.0/2380.78.180.1 to 80.78.181.25480.78.181.255510
9280.78.182.0/2380.78.182.1 to 80.78.183.25480.78.183.255510
9380.78.184.0/2380.78.184.1 to 80.78.185.25480.78.185.255510
9480.78.186.0/2380.78.186.1 to 80.78.187.25480.78.187.255510
9580.78.188.0/2380.78.188.1 to 80.78.189.25480.78.189.255510
9680.78.190.0/2380.78.190.1 to 80.78.191.25480.78.191.255510
9780.78.192.0/2380.78.192.1 to 80.78.193.25480.78.193.255510
9880.78.194.0/2380.78.194.1 to 80.78.195.25480.78.195.255510
9980.78.196.0/2380.78.196.1 to 80.78.197.25480.78.197.255510
10080.78.198.0/2380.78.198.1 to 80.78.199.25480.78.199.255510
10180.78.200.0/2380.78.200.1 to 80.78.201.25480.78.201.255510
10280.78.202.0/2380.78.202.1 to 80.78.203.25480.78.203.255510
10380.78.204.0/2380.78.204.1 to 80.78.205.25480.78.205.255510
10480.78.206.0/2380.78.206.1 to 80.78.207.25480.78.207.255510
10580.78.208.0/2380.78.208.1 to 80.78.209.25480.78.209.255510
10680.78.210.0/2380.78.210.1 to 80.78.211.25480.78.211.255510
10780.78.212.0/2380.78.212.1 to 80.78.213.25480.78.213.255510
10880.78.214.0/2380.78.214.1 to 80.78.215.25480.78.215.255510
10980.78.216.0/2380.78.216.1 to 80.78.217.25480.78.217.255510
11080.78.218.0/2380.78.218.1 to 80.78.219.25480.78.219.255510
11180.78.220.0/2380.78.220.1 to 80.78.221.25480.78.221.255510
11280.78.222.0/2380.78.222.1 to 80.78.223.25480.78.223.255510
11380.78.224.0/2380.78.224.1 to 80.78.225.25480.78.225.255510
11480.78.226.0/2380.78.226.1 to 80.78.227.25480.78.227.255510
11580.78.228.0/2380.78.228.1 to 80.78.229.25480.78.229.255510
11680.78.230.0/2380.78.230.1 to 80.78.231.25480.78.231.255510
11780.78.232.0/2380.78.232.1 to 80.78.233.25480.78.233.255510
11880.78.234.0/2380.78.234.1 to 80.78.235.25480.78.235.255510
11980.78.236.0/2380.78.236.1 to 80.78.237.25480.78.237.255510
12080.78.238.0/2380.78.238.1 to 80.78.239.25480.78.239.255510
12180.78.240.0/2380.78.240.1 to 80.78.241.25480.78.241.255510
12280.78.242.0/2380.78.242.1 to 80.78.243.25480.78.243.255510
12380.78.244.0/2380.78.244.1 to 80.78.245.25480.78.245.255510
12480.78.246.0/2380.78.246.1 to 80.78.247.25480.78.247.255510
12580.78.248.0/2380.78.248.1 to 80.78.249.25480.78.249.255510
12680.78.250.0/2380.78.250.1 to 80.78.251.25480.78.251.255510
12780.78.252.0/2380.78.252.1 to 80.78.253.25480.78.253.255510
12880.78.254.0/2380.78.254.1 to 80.78.255.25480.78.255.255510
12980.79.0.0/2380.79.0.1 to 80.79.1.25480.79.1.255510
13080.79.2.0/2380.79.2.1 to 80.79.3.25480.79.3.255510
13180.79.4.0/2380.79.4.1 to 80.79.5.25480.79.5.255510
13280.79.6.0/2380.79.6.1 to 80.79.7.25480.79.7.255510
13380.79.8.0/2380.79.8.1 to 80.79.9.25480.79.9.255510
13480.79.10.0/2380.79.10.1 to 80.79.11.25480.79.11.255510
13580.79.12.0/2380.79.12.1 to 80.79.13.25480.79.13.255510
13680.79.14.0/2380.79.14.1 to 80.79.15.25480.79.15.255510
13780.79.16.0/2380.79.16.1 to 80.79.17.25480.79.17.255510
13880.79.18.0/2380.79.18.1 to 80.79.19.25480.79.19.255510
13980.79.20.0/2380.79.20.1 to 80.79.21.25480.79.21.255510
14080.79.22.0/2380.79.22.1 to 80.79.23.25480.79.23.255510
14180.79.24.0/2380.79.24.1 to 80.79.25.25480.79.25.255510
14280.79.26.0/2380.79.26.1 to 80.79.27.25480.79.27.255510
14380.79.28.0/2380.79.28.1 to 80.79.29.25480.79.29.255510
14480.79.30.0/2380.79.30.1 to 80.79.31.25480.79.31.255510
14580.79.32.0/2380.79.32.1 to 80.79.33.25480.79.33.255510
14680.79.34.0/2380.79.34.1 to 80.79.35.25480.79.35.255510
14780.79.36.0/2380.79.36.1 to 80.79.37.25480.79.37.255510
14880.79.38.0/2380.79.38.1 to 80.79.39.25480.79.39.255510
14980.79.40.0/2380.79.40.1 to 80.79.41.25480.79.41.255510
15080.79.42.0/2380.79.42.1 to 80.79.43.25480.79.43.255510
15180.79.44.0/2380.79.44.1 to 80.79.45.25480.79.45.255510
15280.79.46.0/2380.79.46.1 to 80.79.47.25480.79.47.255510
15380.79.48.0/2380.79.48.1 to 80.79.49.25480.79.49.255510
15480.79.50.0/2380.79.50.1 to 80.79.51.25480.79.51.255510
15580.79.52.0/2380.79.52.1 to 80.79.53.25480.79.53.255510
15680.79.54.0/2380.79.54.1 to 80.79.55.25480.79.55.255510
15780.79.56.0/2380.79.56.1 to 80.79.57.25480.79.57.255510
15880.79.58.0/2380.79.58.1 to 80.79.59.25480.79.59.255510
15980.79.60.0/2380.79.60.1 to 80.79.61.25480.79.61.255510
16080.79.62.0/2380.79.62.1 to 80.79.63.25480.79.63.255510
16180.79.64.0/2380.79.64.1 to 80.79.65.25480.79.65.255510
16280.79.66.0/2380.79.66.1 to 80.79.67.25480.79.67.255510
16380.79.68.0/2380.79.68.1 to 80.79.69.25480.79.69.255510
16480.79.70.0/2380.79.70.1 to 80.79.71.25480.79.71.255510
16580.79.72.0/2380.79.72.1 to 80.79.73.25480.79.73.255510
16680.79.74.0/2380.79.74.1 to 80.79.75.25480.79.75.255510
16780.79.76.0/2380.79.76.1 to 80.79.77.25480.79.77.255510
16880.79.78.0/2380.79.78.1 to 80.79.79.25480.79.79.255510
16980.79.80.0/2380.79.80.1 to 80.79.81.25480.79.81.255510
17080.79.82.0/2380.79.82.1 to 80.79.83.25480.79.83.255510
17180.79.84.0/2380.79.84.1 to 80.79.85.25480.79.85.255510
17280.79.86.0/2380.79.86.1 to 80.79.87.25480.79.87.255510
17380.79.88.0/2380.79.88.1 to 80.79.89.25480.79.89.255510
17480.79.90.0/2380.79.90.1 to 80.79.91.25480.79.91.255510
17580.79.92.0/2380.79.92.1 to 80.79.93.25480.79.93.255510
17680.79.94.0/2380.79.94.1 to 80.79.95.25480.79.95.255510
17780.79.96.0/2380.79.96.1 to 80.79.97.25480.79.97.255510
17880.79.98.0/2380.79.98.1 to 80.79.99.25480.79.99.255510
17980.79.100.0/2380.79.100.1 to 80.79.101.25480.79.101.255510
18080.79.102.0/2380.79.102.1 to 80.79.103.25480.79.103.255510
18180.79.104.0/2380.79.104.1 to 80.79.105.25480.79.105.255510
18280.79.106.0/2380.79.106.1 to 80.79.107.25480.79.107.255510
18380.79.108.0/2380.79.108.1 to 80.79.109.25480.79.109.255510
18480.79.110.0/2380.79.110.1 to 80.79.111.25480.79.111.255510
18580.79.112.0/2380.79.112.1 to 80.79.113.25480.79.113.255510
18680.79.114.0/2380.79.114.1 to 80.79.115.25480.79.115.255510
18780.79.116.0/2380.79.116.1 to 80.79.117.25480.79.117.255510
18880.79.118.0/2380.79.118.1 to 80.79.119.25480.79.119.255510
18980.79.120.0/2380.79.120.1 to 80.79.121.25480.79.121.255510
19080.79.122.0/2380.79.122.1 to 80.79.123.25480.79.123.255510
19180.79.124.0/2380.79.124.1 to 80.79.125.25480.79.125.255510
19280.79.126.0/2380.79.126.1 to 80.79.127.25480.79.127.255510
19380.79.128.0/2380.79.128.1 to 80.79.129.25480.79.129.255510
19480.79.130.0/2380.79.130.1 to 80.79.131.25480.79.131.255510
19580.79.132.0/2380.79.132.1 to 80.79.133.25480.79.133.255510
19680.79.134.0/2380.79.134.1 to 80.79.135.25480.79.135.255510
19780.79.136.0/2380.79.136.1 to 80.79.137.25480.79.137.255510
19880.79.138.0/2380.79.138.1 to 80.79.139.25480.79.139.255510
19980.79.140.0/2380.79.140.1 to 80.79.141.25480.79.141.255510
20080.79.142.0/2380.79.142.1 to 80.79.143.25480.79.143.255510
20180.79.144.0/2380.79.144.1 to 80.79.145.25480.79.145.255510
20280.79.146.0/2380.79.146.1 to 80.79.147.25480.79.147.255510
20380.79.148.0/2380.79.148.1 to 80.79.149.25480.79.149.255510
20480.79.150.0/2380.79.150.1 to 80.79.151.25480.79.151.255510
20580.79.152.0/2380.79.152.1 to 80.79.153.25480.79.153.255510
20680.79.154.0/2380.79.154.1 to 80.79.155.25480.79.155.255510
20780.79.156.0/2380.79.156.1 to 80.79.157.25480.79.157.255510
20880.79.158.0/2380.79.158.1 to 80.79.159.25480.79.159.255510
20980.79.160.0/2380.79.160.1 to 80.79.161.25480.79.161.255510
21080.79.162.0/2380.79.162.1 to 80.79.163.25480.79.163.255510
21180.79.164.0/2380.79.164.1 to 80.79.165.25480.79.165.255510
21280.79.166.0/2380.79.166.1 to 80.79.167.25480.79.167.255510
21380.79.168.0/2380.79.168.1 to 80.79.169.25480.79.169.255510
21480.79.170.0/2380.79.170.1 to 80.79.171.25480.79.171.255510
21580.79.172.0/2380.79.172.1 to 80.79.173.25480.79.173.255510
21680.79.174.0/2380.79.174.1 to 80.79.175.25480.79.175.255510
21780.79.176.0/2380.79.176.1 to 80.79.177.25480.79.177.255510
21880.79.178.0/2380.79.178.1 to 80.79.179.25480.79.179.255510
21980.79.180.0/2380.79.180.1 to 80.79.181.25480.79.181.255510
22080.79.182.0/2380.79.182.1 to 80.79.183.25480.79.183.255510
22180.79.184.0/2380.79.184.1 to 80.79.185.25480.79.185.255510
22280.79.186.0/2380.79.186.1 to 80.79.187.25480.79.187.255510
22380.79.188.0/2380.79.188.1 to 80.79.189.25480.79.189.255510
22480.79.190.0/2380.79.190.1 to 80.79.191.25480.79.191.255510
22580.79.192.0/2380.79.192.1 to 80.79.193.25480.79.193.255510
22680.79.194.0/2380.79.194.1 to 80.79.195.25480.79.195.255510
22780.79.196.0/2380.79.196.1 to 80.79.197.25480.79.197.255510
22880.79.198.0/2380.79.198.1 to 80.79.199.25480.79.199.255510
22980.79.200.0/2380.79.200.1 to 80.79.201.25480.79.201.255510
23080.79.202.0/2380.79.202.1 to 80.79.203.25480.79.203.255510
23180.79.204.0/2380.79.204.1 to 80.79.205.25480.79.205.255510
23280.79.206.0/2380.79.206.1 to 80.79.207.25480.79.207.255510
23380.79.208.0/2380.79.208.1 to 80.79.209.25480.79.209.255510
23480.79.210.0/2380.79.210.1 to 80.79.211.25480.79.211.255510
23580.79.212.0/2380.79.212.1 to 80.79.213.25480.79.213.255510
23680.79.214.0/2380.79.214.1 to 80.79.215.25480.79.215.255510
23780.79.216.0/2380.79.216.1 to 80.79.217.25480.79.217.255510
23880.79.218.0/2380.79.218.1 to 80.79.219.25480.79.219.255510
23980.79.220.0/2380.79.220.1 to 80.79.221.25480.79.221.255510
24080.79.222.0/2380.79.222.1 to 80.79.223.25480.79.223.255510
24180.79.224.0/2380.79.224.1 to 80.79.225.25480.79.225.255510
24280.79.226.0/2380.79.226.1 to 80.79.227.25480.79.227.255510
24380.79.228.0/2380.79.228.1 to 80.79.229.25480.79.229.255510
24480.79.230.0/2380.79.230.1 to 80.79.231.25480.79.231.255510
24580.79.232.0/2380.79.232.1 to 80.79.233.25480.79.233.255510
24680.79.234.0/2380.79.234.1 to 80.79.235.25480.79.235.255510
24780.79.236.0/2380.79.236.1 to 80.79.237.25480.79.237.255510
24880.79.238.0/2380.79.238.1 to 80.79.239.25480.79.239.255510
24980.79.240.0/2380.79.240.1 to 80.79.241.25480.79.241.255510
25080.79.242.0/2380.79.242.1 to 80.79.243.25480.79.243.255510
25180.79.244.0/2380.79.244.1 to 80.79.245.25480.79.245.255510
25280.79.246.0/2380.79.246.1 to 80.79.247.25480.79.247.255510
25380.79.248.0/2380.79.248.1 to 80.79.249.25480.79.249.255510
25480.79.250.0/2380.79.250.1 to 80.79.251.25480.79.251.255510
25580.79.252.0/2380.79.252.1 to 80.79.253.25480.79.253.255510
25680.79.254.0/2380.79.254.1 to 80.79.255.25480.79.255.255510

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