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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.

Network55.32.0.0/15
Usable hosts131,070
Subnet mask255.254.0.0
Addresses131,072
Network address
55.32.0.0
Broadcast address
55.33.255.255
First usable
55.32.0.1
Last usable
55.33.255.254
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 37200000 · Integer 924844032 to 924975103
Reverse DNS zones
32.55.in-addr.arpa
33.55.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
Address00110111.00100000.00000000.0000000055.32.0.0
Subnet mask11111111.11111110.00000000.00000000255.254.0.0
Network00110111.00100000.00000000.0000000055.32.0.0
Broadcast00110111.00100001.11111111.1111111155.33.255.255
Split into smaller subnets/23

55.32.0.0/15 makes 256 subnets of /23.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
155.32.0.0/2355.32.0.1 to 55.32.1.25455.32.1.255510
255.32.2.0/2355.32.2.1 to 55.32.3.25455.32.3.255510
355.32.4.0/2355.32.4.1 to 55.32.5.25455.32.5.255510
455.32.6.0/2355.32.6.1 to 55.32.7.25455.32.7.255510
555.32.8.0/2355.32.8.1 to 55.32.9.25455.32.9.255510
655.32.10.0/2355.32.10.1 to 55.32.11.25455.32.11.255510
755.32.12.0/2355.32.12.1 to 55.32.13.25455.32.13.255510
855.32.14.0/2355.32.14.1 to 55.32.15.25455.32.15.255510
955.32.16.0/2355.32.16.1 to 55.32.17.25455.32.17.255510
1055.32.18.0/2355.32.18.1 to 55.32.19.25455.32.19.255510
1155.32.20.0/2355.32.20.1 to 55.32.21.25455.32.21.255510
1255.32.22.0/2355.32.22.1 to 55.32.23.25455.32.23.255510
1355.32.24.0/2355.32.24.1 to 55.32.25.25455.32.25.255510
1455.32.26.0/2355.32.26.1 to 55.32.27.25455.32.27.255510
1555.32.28.0/2355.32.28.1 to 55.32.29.25455.32.29.255510
1655.32.30.0/2355.32.30.1 to 55.32.31.25455.32.31.255510
1755.32.32.0/2355.32.32.1 to 55.32.33.25455.32.33.255510
1855.32.34.0/2355.32.34.1 to 55.32.35.25455.32.35.255510
1955.32.36.0/2355.32.36.1 to 55.32.37.25455.32.37.255510
2055.32.38.0/2355.32.38.1 to 55.32.39.25455.32.39.255510
2155.32.40.0/2355.32.40.1 to 55.32.41.25455.32.41.255510
2255.32.42.0/2355.32.42.1 to 55.32.43.25455.32.43.255510
2355.32.44.0/2355.32.44.1 to 55.32.45.25455.32.45.255510
2455.32.46.0/2355.32.46.1 to 55.32.47.25455.32.47.255510
2555.32.48.0/2355.32.48.1 to 55.32.49.25455.32.49.255510
2655.32.50.0/2355.32.50.1 to 55.32.51.25455.32.51.255510
2755.32.52.0/2355.32.52.1 to 55.32.53.25455.32.53.255510
2855.32.54.0/2355.32.54.1 to 55.32.55.25455.32.55.255510
2955.32.56.0/2355.32.56.1 to 55.32.57.25455.32.57.255510
3055.32.58.0/2355.32.58.1 to 55.32.59.25455.32.59.255510
3155.32.60.0/2355.32.60.1 to 55.32.61.25455.32.61.255510
3255.32.62.0/2355.32.62.1 to 55.32.63.25455.32.63.255510
3355.32.64.0/2355.32.64.1 to 55.32.65.25455.32.65.255510
3455.32.66.0/2355.32.66.1 to 55.32.67.25455.32.67.255510
3555.32.68.0/2355.32.68.1 to 55.32.69.25455.32.69.255510
3655.32.70.0/2355.32.70.1 to 55.32.71.25455.32.71.255510
3755.32.72.0/2355.32.72.1 to 55.32.73.25455.32.73.255510
3855.32.74.0/2355.32.74.1 to 55.32.75.25455.32.75.255510
3955.32.76.0/2355.32.76.1 to 55.32.77.25455.32.77.255510
4055.32.78.0/2355.32.78.1 to 55.32.79.25455.32.79.255510
4155.32.80.0/2355.32.80.1 to 55.32.81.25455.32.81.255510
4255.32.82.0/2355.32.82.1 to 55.32.83.25455.32.83.255510
4355.32.84.0/2355.32.84.1 to 55.32.85.25455.32.85.255510
4455.32.86.0/2355.32.86.1 to 55.32.87.25455.32.87.255510
4555.32.88.0/2355.32.88.1 to 55.32.89.25455.32.89.255510
4655.32.90.0/2355.32.90.1 to 55.32.91.25455.32.91.255510
4755.32.92.0/2355.32.92.1 to 55.32.93.25455.32.93.255510
4855.32.94.0/2355.32.94.1 to 55.32.95.25455.32.95.255510
4955.32.96.0/2355.32.96.1 to 55.32.97.25455.32.97.255510
5055.32.98.0/2355.32.98.1 to 55.32.99.25455.32.99.255510
5155.32.100.0/2355.32.100.1 to 55.32.101.25455.32.101.255510
5255.32.102.0/2355.32.102.1 to 55.32.103.25455.32.103.255510
5355.32.104.0/2355.32.104.1 to 55.32.105.25455.32.105.255510
5455.32.106.0/2355.32.106.1 to 55.32.107.25455.32.107.255510
5555.32.108.0/2355.32.108.1 to 55.32.109.25455.32.109.255510
5655.32.110.0/2355.32.110.1 to 55.32.111.25455.32.111.255510
5755.32.112.0/2355.32.112.1 to 55.32.113.25455.32.113.255510
5855.32.114.0/2355.32.114.1 to 55.32.115.25455.32.115.255510
5955.32.116.0/2355.32.116.1 to 55.32.117.25455.32.117.255510
6055.32.118.0/2355.32.118.1 to 55.32.119.25455.32.119.255510
6155.32.120.0/2355.32.120.1 to 55.32.121.25455.32.121.255510
6255.32.122.0/2355.32.122.1 to 55.32.123.25455.32.123.255510
6355.32.124.0/2355.32.124.1 to 55.32.125.25455.32.125.255510
6455.32.126.0/2355.32.126.1 to 55.32.127.25455.32.127.255510
6555.32.128.0/2355.32.128.1 to 55.32.129.25455.32.129.255510
6655.32.130.0/2355.32.130.1 to 55.32.131.25455.32.131.255510
6755.32.132.0/2355.32.132.1 to 55.32.133.25455.32.133.255510
6855.32.134.0/2355.32.134.1 to 55.32.135.25455.32.135.255510
6955.32.136.0/2355.32.136.1 to 55.32.137.25455.32.137.255510
7055.32.138.0/2355.32.138.1 to 55.32.139.25455.32.139.255510
7155.32.140.0/2355.32.140.1 to 55.32.141.25455.32.141.255510
7255.32.142.0/2355.32.142.1 to 55.32.143.25455.32.143.255510
7355.32.144.0/2355.32.144.1 to 55.32.145.25455.32.145.255510
7455.32.146.0/2355.32.146.1 to 55.32.147.25455.32.147.255510
7555.32.148.0/2355.32.148.1 to 55.32.149.25455.32.149.255510
7655.32.150.0/2355.32.150.1 to 55.32.151.25455.32.151.255510
7755.32.152.0/2355.32.152.1 to 55.32.153.25455.32.153.255510
7855.32.154.0/2355.32.154.1 to 55.32.155.25455.32.155.255510
7955.32.156.0/2355.32.156.1 to 55.32.157.25455.32.157.255510
8055.32.158.0/2355.32.158.1 to 55.32.159.25455.32.159.255510
8155.32.160.0/2355.32.160.1 to 55.32.161.25455.32.161.255510
8255.32.162.0/2355.32.162.1 to 55.32.163.25455.32.163.255510
8355.32.164.0/2355.32.164.1 to 55.32.165.25455.32.165.255510
8455.32.166.0/2355.32.166.1 to 55.32.167.25455.32.167.255510
8555.32.168.0/2355.32.168.1 to 55.32.169.25455.32.169.255510
8655.32.170.0/2355.32.170.1 to 55.32.171.25455.32.171.255510
8755.32.172.0/2355.32.172.1 to 55.32.173.25455.32.173.255510
8855.32.174.0/2355.32.174.1 to 55.32.175.25455.32.175.255510
8955.32.176.0/2355.32.176.1 to 55.32.177.25455.32.177.255510
9055.32.178.0/2355.32.178.1 to 55.32.179.25455.32.179.255510
9155.32.180.0/2355.32.180.1 to 55.32.181.25455.32.181.255510
9255.32.182.0/2355.32.182.1 to 55.32.183.25455.32.183.255510
9355.32.184.0/2355.32.184.1 to 55.32.185.25455.32.185.255510
9455.32.186.0/2355.32.186.1 to 55.32.187.25455.32.187.255510
9555.32.188.0/2355.32.188.1 to 55.32.189.25455.32.189.255510
9655.32.190.0/2355.32.190.1 to 55.32.191.25455.32.191.255510
9755.32.192.0/2355.32.192.1 to 55.32.193.25455.32.193.255510
9855.32.194.0/2355.32.194.1 to 55.32.195.25455.32.195.255510
9955.32.196.0/2355.32.196.1 to 55.32.197.25455.32.197.255510
10055.32.198.0/2355.32.198.1 to 55.32.199.25455.32.199.255510
10155.32.200.0/2355.32.200.1 to 55.32.201.25455.32.201.255510
10255.32.202.0/2355.32.202.1 to 55.32.203.25455.32.203.255510
10355.32.204.0/2355.32.204.1 to 55.32.205.25455.32.205.255510
10455.32.206.0/2355.32.206.1 to 55.32.207.25455.32.207.255510
10555.32.208.0/2355.32.208.1 to 55.32.209.25455.32.209.255510
10655.32.210.0/2355.32.210.1 to 55.32.211.25455.32.211.255510
10755.32.212.0/2355.32.212.1 to 55.32.213.25455.32.213.255510
10855.32.214.0/2355.32.214.1 to 55.32.215.25455.32.215.255510
10955.32.216.0/2355.32.216.1 to 55.32.217.25455.32.217.255510
11055.32.218.0/2355.32.218.1 to 55.32.219.25455.32.219.255510
11155.32.220.0/2355.32.220.1 to 55.32.221.25455.32.221.255510
11255.32.222.0/2355.32.222.1 to 55.32.223.25455.32.223.255510
11355.32.224.0/2355.32.224.1 to 55.32.225.25455.32.225.255510
11455.32.226.0/2355.32.226.1 to 55.32.227.25455.32.227.255510
11555.32.228.0/2355.32.228.1 to 55.32.229.25455.32.229.255510
11655.32.230.0/2355.32.230.1 to 55.32.231.25455.32.231.255510
11755.32.232.0/2355.32.232.1 to 55.32.233.25455.32.233.255510
11855.32.234.0/2355.32.234.1 to 55.32.235.25455.32.235.255510
11955.32.236.0/2355.32.236.1 to 55.32.237.25455.32.237.255510
12055.32.238.0/2355.32.238.1 to 55.32.239.25455.32.239.255510
12155.32.240.0/2355.32.240.1 to 55.32.241.25455.32.241.255510
12255.32.242.0/2355.32.242.1 to 55.32.243.25455.32.243.255510
12355.32.244.0/2355.32.244.1 to 55.32.245.25455.32.245.255510
12455.32.246.0/2355.32.246.1 to 55.32.247.25455.32.247.255510
12555.32.248.0/2355.32.248.1 to 55.32.249.25455.32.249.255510
12655.32.250.0/2355.32.250.1 to 55.32.251.25455.32.251.255510
12755.32.252.0/2355.32.252.1 to 55.32.253.25455.32.253.255510
12855.32.254.0/2355.32.254.1 to 55.32.255.25455.32.255.255510
12955.33.0.0/2355.33.0.1 to 55.33.1.25455.33.1.255510
13055.33.2.0/2355.33.2.1 to 55.33.3.25455.33.3.255510
13155.33.4.0/2355.33.4.1 to 55.33.5.25455.33.5.255510
13255.33.6.0/2355.33.6.1 to 55.33.7.25455.33.7.255510
13355.33.8.0/2355.33.8.1 to 55.33.9.25455.33.9.255510
13455.33.10.0/2355.33.10.1 to 55.33.11.25455.33.11.255510
13555.33.12.0/2355.33.12.1 to 55.33.13.25455.33.13.255510
13655.33.14.0/2355.33.14.1 to 55.33.15.25455.33.15.255510
13755.33.16.0/2355.33.16.1 to 55.33.17.25455.33.17.255510
13855.33.18.0/2355.33.18.1 to 55.33.19.25455.33.19.255510
13955.33.20.0/2355.33.20.1 to 55.33.21.25455.33.21.255510
14055.33.22.0/2355.33.22.1 to 55.33.23.25455.33.23.255510
14155.33.24.0/2355.33.24.1 to 55.33.25.25455.33.25.255510
14255.33.26.0/2355.33.26.1 to 55.33.27.25455.33.27.255510
14355.33.28.0/2355.33.28.1 to 55.33.29.25455.33.29.255510
14455.33.30.0/2355.33.30.1 to 55.33.31.25455.33.31.255510
14555.33.32.0/2355.33.32.1 to 55.33.33.25455.33.33.255510
14655.33.34.0/2355.33.34.1 to 55.33.35.25455.33.35.255510
14755.33.36.0/2355.33.36.1 to 55.33.37.25455.33.37.255510
14855.33.38.0/2355.33.38.1 to 55.33.39.25455.33.39.255510
14955.33.40.0/2355.33.40.1 to 55.33.41.25455.33.41.255510
15055.33.42.0/2355.33.42.1 to 55.33.43.25455.33.43.255510
15155.33.44.0/2355.33.44.1 to 55.33.45.25455.33.45.255510
15255.33.46.0/2355.33.46.1 to 55.33.47.25455.33.47.255510
15355.33.48.0/2355.33.48.1 to 55.33.49.25455.33.49.255510
15455.33.50.0/2355.33.50.1 to 55.33.51.25455.33.51.255510
15555.33.52.0/2355.33.52.1 to 55.33.53.25455.33.53.255510
15655.33.54.0/2355.33.54.1 to 55.33.55.25455.33.55.255510
15755.33.56.0/2355.33.56.1 to 55.33.57.25455.33.57.255510
15855.33.58.0/2355.33.58.1 to 55.33.59.25455.33.59.255510
15955.33.60.0/2355.33.60.1 to 55.33.61.25455.33.61.255510
16055.33.62.0/2355.33.62.1 to 55.33.63.25455.33.63.255510
16155.33.64.0/2355.33.64.1 to 55.33.65.25455.33.65.255510
16255.33.66.0/2355.33.66.1 to 55.33.67.25455.33.67.255510
16355.33.68.0/2355.33.68.1 to 55.33.69.25455.33.69.255510
16455.33.70.0/2355.33.70.1 to 55.33.71.25455.33.71.255510
16555.33.72.0/2355.33.72.1 to 55.33.73.25455.33.73.255510
16655.33.74.0/2355.33.74.1 to 55.33.75.25455.33.75.255510
16755.33.76.0/2355.33.76.1 to 55.33.77.25455.33.77.255510
16855.33.78.0/2355.33.78.1 to 55.33.79.25455.33.79.255510
16955.33.80.0/2355.33.80.1 to 55.33.81.25455.33.81.255510
17055.33.82.0/2355.33.82.1 to 55.33.83.25455.33.83.255510
17155.33.84.0/2355.33.84.1 to 55.33.85.25455.33.85.255510
17255.33.86.0/2355.33.86.1 to 55.33.87.25455.33.87.255510
17355.33.88.0/2355.33.88.1 to 55.33.89.25455.33.89.255510
17455.33.90.0/2355.33.90.1 to 55.33.91.25455.33.91.255510
17555.33.92.0/2355.33.92.1 to 55.33.93.25455.33.93.255510
17655.33.94.0/2355.33.94.1 to 55.33.95.25455.33.95.255510
17755.33.96.0/2355.33.96.1 to 55.33.97.25455.33.97.255510
17855.33.98.0/2355.33.98.1 to 55.33.99.25455.33.99.255510
17955.33.100.0/2355.33.100.1 to 55.33.101.25455.33.101.255510
18055.33.102.0/2355.33.102.1 to 55.33.103.25455.33.103.255510
18155.33.104.0/2355.33.104.1 to 55.33.105.25455.33.105.255510
18255.33.106.0/2355.33.106.1 to 55.33.107.25455.33.107.255510
18355.33.108.0/2355.33.108.1 to 55.33.109.25455.33.109.255510
18455.33.110.0/2355.33.110.1 to 55.33.111.25455.33.111.255510
18555.33.112.0/2355.33.112.1 to 55.33.113.25455.33.113.255510
18655.33.114.0/2355.33.114.1 to 55.33.115.25455.33.115.255510
18755.33.116.0/2355.33.116.1 to 55.33.117.25455.33.117.255510
18855.33.118.0/2355.33.118.1 to 55.33.119.25455.33.119.255510
18955.33.120.0/2355.33.120.1 to 55.33.121.25455.33.121.255510
19055.33.122.0/2355.33.122.1 to 55.33.123.25455.33.123.255510
19155.33.124.0/2355.33.124.1 to 55.33.125.25455.33.125.255510
19255.33.126.0/2355.33.126.1 to 55.33.127.25455.33.127.255510
19355.33.128.0/2355.33.128.1 to 55.33.129.25455.33.129.255510
19455.33.130.0/2355.33.130.1 to 55.33.131.25455.33.131.255510
19555.33.132.0/2355.33.132.1 to 55.33.133.25455.33.133.255510
19655.33.134.0/2355.33.134.1 to 55.33.135.25455.33.135.255510
19755.33.136.0/2355.33.136.1 to 55.33.137.25455.33.137.255510
19855.33.138.0/2355.33.138.1 to 55.33.139.25455.33.139.255510
19955.33.140.0/2355.33.140.1 to 55.33.141.25455.33.141.255510
20055.33.142.0/2355.33.142.1 to 55.33.143.25455.33.143.255510
20155.33.144.0/2355.33.144.1 to 55.33.145.25455.33.145.255510
20255.33.146.0/2355.33.146.1 to 55.33.147.25455.33.147.255510
20355.33.148.0/2355.33.148.1 to 55.33.149.25455.33.149.255510
20455.33.150.0/2355.33.150.1 to 55.33.151.25455.33.151.255510
20555.33.152.0/2355.33.152.1 to 55.33.153.25455.33.153.255510
20655.33.154.0/2355.33.154.1 to 55.33.155.25455.33.155.255510
20755.33.156.0/2355.33.156.1 to 55.33.157.25455.33.157.255510
20855.33.158.0/2355.33.158.1 to 55.33.159.25455.33.159.255510
20955.33.160.0/2355.33.160.1 to 55.33.161.25455.33.161.255510
21055.33.162.0/2355.33.162.1 to 55.33.163.25455.33.163.255510
21155.33.164.0/2355.33.164.1 to 55.33.165.25455.33.165.255510
21255.33.166.0/2355.33.166.1 to 55.33.167.25455.33.167.255510
21355.33.168.0/2355.33.168.1 to 55.33.169.25455.33.169.255510
21455.33.170.0/2355.33.170.1 to 55.33.171.25455.33.171.255510
21555.33.172.0/2355.33.172.1 to 55.33.173.25455.33.173.255510
21655.33.174.0/2355.33.174.1 to 55.33.175.25455.33.175.255510
21755.33.176.0/2355.33.176.1 to 55.33.177.25455.33.177.255510
21855.33.178.0/2355.33.178.1 to 55.33.179.25455.33.179.255510
21955.33.180.0/2355.33.180.1 to 55.33.181.25455.33.181.255510
22055.33.182.0/2355.33.182.1 to 55.33.183.25455.33.183.255510
22155.33.184.0/2355.33.184.1 to 55.33.185.25455.33.185.255510
22255.33.186.0/2355.33.186.1 to 55.33.187.25455.33.187.255510
22355.33.188.0/2355.33.188.1 to 55.33.189.25455.33.189.255510
22455.33.190.0/2355.33.190.1 to 55.33.191.25455.33.191.255510
22555.33.192.0/2355.33.192.1 to 55.33.193.25455.33.193.255510
22655.33.194.0/2355.33.194.1 to 55.33.195.25455.33.195.255510
22755.33.196.0/2355.33.196.1 to 55.33.197.25455.33.197.255510
22855.33.198.0/2355.33.198.1 to 55.33.199.25455.33.199.255510
22955.33.200.0/2355.33.200.1 to 55.33.201.25455.33.201.255510
23055.33.202.0/2355.33.202.1 to 55.33.203.25455.33.203.255510
23155.33.204.0/2355.33.204.1 to 55.33.205.25455.33.205.255510
23255.33.206.0/2355.33.206.1 to 55.33.207.25455.33.207.255510
23355.33.208.0/2355.33.208.1 to 55.33.209.25455.33.209.255510
23455.33.210.0/2355.33.210.1 to 55.33.211.25455.33.211.255510
23555.33.212.0/2355.33.212.1 to 55.33.213.25455.33.213.255510
23655.33.214.0/2355.33.214.1 to 55.33.215.25455.33.215.255510
23755.33.216.0/2355.33.216.1 to 55.33.217.25455.33.217.255510
23855.33.218.0/2355.33.218.1 to 55.33.219.25455.33.219.255510
23955.33.220.0/2355.33.220.1 to 55.33.221.25455.33.221.255510
24055.33.222.0/2355.33.222.1 to 55.33.223.25455.33.223.255510
24155.33.224.0/2355.33.224.1 to 55.33.225.25455.33.225.255510
24255.33.226.0/2355.33.226.1 to 55.33.227.25455.33.227.255510
24355.33.228.0/2355.33.228.1 to 55.33.229.25455.33.229.255510
24455.33.230.0/2355.33.230.1 to 55.33.231.25455.33.231.255510
24555.33.232.0/2355.33.232.1 to 55.33.233.25455.33.233.255510
24655.33.234.0/2355.33.234.1 to 55.33.235.25455.33.235.255510
24755.33.236.0/2355.33.236.1 to 55.33.237.25455.33.237.255510
24855.33.238.0/2355.33.238.1 to 55.33.239.25455.33.239.255510
24955.33.240.0/2355.33.240.1 to 55.33.241.25455.33.241.255510
25055.33.242.0/2355.33.242.1 to 55.33.243.25455.33.243.255510
25155.33.244.0/2355.33.244.1 to 55.33.245.25455.33.245.255510
25255.33.246.0/2355.33.246.1 to 55.33.247.25455.33.247.255510
25355.33.248.0/2355.33.248.1 to 55.33.249.25455.33.249.255510
25455.33.250.0/2355.33.250.1 to 55.33.251.25455.33.251.255510
25555.33.252.0/2355.33.252.1 to 55.33.253.25455.33.253.255510
25655.33.254.0/2355.33.254.1 to 55.33.255.25455.33.255.255510

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