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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.

Network86.131.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
86.131.0.0
Broadcast address
86.131.255.255
First usable
86.131.0.1
Last usable
86.131.255.254
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 56830000 · Integer 1451425792 to 1451491327
Reverse DNS zone
131.86.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010110.10000011..00000000.0000000086.131.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01010110.10000011..00000000.0000000086.131.0.0
Broadcast01010110.10000011..11111111.1111111186.131.255.255
Split into smaller subnets/24

86.131.0.0/16 makes 256 subnets of /24.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
186.131.0.0/2486.131.0.1 to 86.131.0.25486.131.0.255254
286.131.1.0/2486.131.1.1 to 86.131.1.25486.131.1.255254
386.131.2.0/2486.131.2.1 to 86.131.2.25486.131.2.255254
486.131.3.0/2486.131.3.1 to 86.131.3.25486.131.3.255254
586.131.4.0/2486.131.4.1 to 86.131.4.25486.131.4.255254
686.131.5.0/2486.131.5.1 to 86.131.5.25486.131.5.255254
786.131.6.0/2486.131.6.1 to 86.131.6.25486.131.6.255254
886.131.7.0/2486.131.7.1 to 86.131.7.25486.131.7.255254
986.131.8.0/2486.131.8.1 to 86.131.8.25486.131.8.255254
1086.131.9.0/2486.131.9.1 to 86.131.9.25486.131.9.255254
1186.131.10.0/2486.131.10.1 to 86.131.10.25486.131.10.255254
1286.131.11.0/2486.131.11.1 to 86.131.11.25486.131.11.255254
1386.131.12.0/2486.131.12.1 to 86.131.12.25486.131.12.255254
1486.131.13.0/2486.131.13.1 to 86.131.13.25486.131.13.255254
1586.131.14.0/2486.131.14.1 to 86.131.14.25486.131.14.255254
1686.131.15.0/2486.131.15.1 to 86.131.15.25486.131.15.255254
1786.131.16.0/2486.131.16.1 to 86.131.16.25486.131.16.255254
1886.131.17.0/2486.131.17.1 to 86.131.17.25486.131.17.255254
1986.131.18.0/2486.131.18.1 to 86.131.18.25486.131.18.255254
2086.131.19.0/2486.131.19.1 to 86.131.19.25486.131.19.255254
2186.131.20.0/2486.131.20.1 to 86.131.20.25486.131.20.255254
2286.131.21.0/2486.131.21.1 to 86.131.21.25486.131.21.255254
2386.131.22.0/2486.131.22.1 to 86.131.22.25486.131.22.255254
2486.131.23.0/2486.131.23.1 to 86.131.23.25486.131.23.255254
2586.131.24.0/2486.131.24.1 to 86.131.24.25486.131.24.255254
2686.131.25.0/2486.131.25.1 to 86.131.25.25486.131.25.255254
2786.131.26.0/2486.131.26.1 to 86.131.26.25486.131.26.255254
2886.131.27.0/2486.131.27.1 to 86.131.27.25486.131.27.255254
2986.131.28.0/2486.131.28.1 to 86.131.28.25486.131.28.255254
3086.131.29.0/2486.131.29.1 to 86.131.29.25486.131.29.255254
3186.131.30.0/2486.131.30.1 to 86.131.30.25486.131.30.255254
3286.131.31.0/2486.131.31.1 to 86.131.31.25486.131.31.255254
3386.131.32.0/2486.131.32.1 to 86.131.32.25486.131.32.255254
3486.131.33.0/2486.131.33.1 to 86.131.33.25486.131.33.255254
3586.131.34.0/2486.131.34.1 to 86.131.34.25486.131.34.255254
3686.131.35.0/2486.131.35.1 to 86.131.35.25486.131.35.255254
3786.131.36.0/2486.131.36.1 to 86.131.36.25486.131.36.255254
3886.131.37.0/2486.131.37.1 to 86.131.37.25486.131.37.255254
3986.131.38.0/2486.131.38.1 to 86.131.38.25486.131.38.255254
4086.131.39.0/2486.131.39.1 to 86.131.39.25486.131.39.255254
4186.131.40.0/2486.131.40.1 to 86.131.40.25486.131.40.255254
4286.131.41.0/2486.131.41.1 to 86.131.41.25486.131.41.255254
4386.131.42.0/2486.131.42.1 to 86.131.42.25486.131.42.255254
4486.131.43.0/2486.131.43.1 to 86.131.43.25486.131.43.255254
4586.131.44.0/2486.131.44.1 to 86.131.44.25486.131.44.255254
4686.131.45.0/2486.131.45.1 to 86.131.45.25486.131.45.255254
4786.131.46.0/2486.131.46.1 to 86.131.46.25486.131.46.255254
4886.131.47.0/2486.131.47.1 to 86.131.47.25486.131.47.255254
4986.131.48.0/2486.131.48.1 to 86.131.48.25486.131.48.255254
5086.131.49.0/2486.131.49.1 to 86.131.49.25486.131.49.255254
5186.131.50.0/2486.131.50.1 to 86.131.50.25486.131.50.255254
5286.131.51.0/2486.131.51.1 to 86.131.51.25486.131.51.255254
5386.131.52.0/2486.131.52.1 to 86.131.52.25486.131.52.255254
5486.131.53.0/2486.131.53.1 to 86.131.53.25486.131.53.255254
5586.131.54.0/2486.131.54.1 to 86.131.54.25486.131.54.255254
5686.131.55.0/2486.131.55.1 to 86.131.55.25486.131.55.255254
5786.131.56.0/2486.131.56.1 to 86.131.56.25486.131.56.255254
5886.131.57.0/2486.131.57.1 to 86.131.57.25486.131.57.255254
5986.131.58.0/2486.131.58.1 to 86.131.58.25486.131.58.255254
6086.131.59.0/2486.131.59.1 to 86.131.59.25486.131.59.255254
6186.131.60.0/2486.131.60.1 to 86.131.60.25486.131.60.255254
6286.131.61.0/2486.131.61.1 to 86.131.61.25486.131.61.255254
6386.131.62.0/2486.131.62.1 to 86.131.62.25486.131.62.255254
6486.131.63.0/2486.131.63.1 to 86.131.63.25486.131.63.255254
6586.131.64.0/2486.131.64.1 to 86.131.64.25486.131.64.255254
6686.131.65.0/2486.131.65.1 to 86.131.65.25486.131.65.255254
6786.131.66.0/2486.131.66.1 to 86.131.66.25486.131.66.255254
6886.131.67.0/2486.131.67.1 to 86.131.67.25486.131.67.255254
6986.131.68.0/2486.131.68.1 to 86.131.68.25486.131.68.255254
7086.131.69.0/2486.131.69.1 to 86.131.69.25486.131.69.255254
7186.131.70.0/2486.131.70.1 to 86.131.70.25486.131.70.255254
7286.131.71.0/2486.131.71.1 to 86.131.71.25486.131.71.255254
7386.131.72.0/2486.131.72.1 to 86.131.72.25486.131.72.255254
7486.131.73.0/2486.131.73.1 to 86.131.73.25486.131.73.255254
7586.131.74.0/2486.131.74.1 to 86.131.74.25486.131.74.255254
7686.131.75.0/2486.131.75.1 to 86.131.75.25486.131.75.255254
7786.131.76.0/2486.131.76.1 to 86.131.76.25486.131.76.255254
7886.131.77.0/2486.131.77.1 to 86.131.77.25486.131.77.255254
7986.131.78.0/2486.131.78.1 to 86.131.78.25486.131.78.255254
8086.131.79.0/2486.131.79.1 to 86.131.79.25486.131.79.255254
8186.131.80.0/2486.131.80.1 to 86.131.80.25486.131.80.255254
8286.131.81.0/2486.131.81.1 to 86.131.81.25486.131.81.255254
8386.131.82.0/2486.131.82.1 to 86.131.82.25486.131.82.255254
8486.131.83.0/2486.131.83.1 to 86.131.83.25486.131.83.255254
8586.131.84.0/2486.131.84.1 to 86.131.84.25486.131.84.255254
8686.131.85.0/2486.131.85.1 to 86.131.85.25486.131.85.255254
8786.131.86.0/2486.131.86.1 to 86.131.86.25486.131.86.255254
8886.131.87.0/2486.131.87.1 to 86.131.87.25486.131.87.255254
8986.131.88.0/2486.131.88.1 to 86.131.88.25486.131.88.255254
9086.131.89.0/2486.131.89.1 to 86.131.89.25486.131.89.255254
9186.131.90.0/2486.131.90.1 to 86.131.90.25486.131.90.255254
9286.131.91.0/2486.131.91.1 to 86.131.91.25486.131.91.255254
9386.131.92.0/2486.131.92.1 to 86.131.92.25486.131.92.255254
9486.131.93.0/2486.131.93.1 to 86.131.93.25486.131.93.255254
9586.131.94.0/2486.131.94.1 to 86.131.94.25486.131.94.255254
9686.131.95.0/2486.131.95.1 to 86.131.95.25486.131.95.255254
9786.131.96.0/2486.131.96.1 to 86.131.96.25486.131.96.255254
9886.131.97.0/2486.131.97.1 to 86.131.97.25486.131.97.255254
9986.131.98.0/2486.131.98.1 to 86.131.98.25486.131.98.255254
10086.131.99.0/2486.131.99.1 to 86.131.99.25486.131.99.255254
10186.131.100.0/2486.131.100.1 to 86.131.100.25486.131.100.255254
10286.131.101.0/2486.131.101.1 to 86.131.101.25486.131.101.255254
10386.131.102.0/2486.131.102.1 to 86.131.102.25486.131.102.255254
10486.131.103.0/2486.131.103.1 to 86.131.103.25486.131.103.255254
10586.131.104.0/2486.131.104.1 to 86.131.104.25486.131.104.255254
10686.131.105.0/2486.131.105.1 to 86.131.105.25486.131.105.255254
10786.131.106.0/2486.131.106.1 to 86.131.106.25486.131.106.255254
10886.131.107.0/2486.131.107.1 to 86.131.107.25486.131.107.255254
10986.131.108.0/2486.131.108.1 to 86.131.108.25486.131.108.255254
11086.131.109.0/2486.131.109.1 to 86.131.109.25486.131.109.255254
11186.131.110.0/2486.131.110.1 to 86.131.110.25486.131.110.255254
11286.131.111.0/2486.131.111.1 to 86.131.111.25486.131.111.255254
11386.131.112.0/2486.131.112.1 to 86.131.112.25486.131.112.255254
11486.131.113.0/2486.131.113.1 to 86.131.113.25486.131.113.255254
11586.131.114.0/2486.131.114.1 to 86.131.114.25486.131.114.255254
11686.131.115.0/2486.131.115.1 to 86.131.115.25486.131.115.255254
11786.131.116.0/2486.131.116.1 to 86.131.116.25486.131.116.255254
11886.131.117.0/2486.131.117.1 to 86.131.117.25486.131.117.255254
11986.131.118.0/2486.131.118.1 to 86.131.118.25486.131.118.255254
12086.131.119.0/2486.131.119.1 to 86.131.119.25486.131.119.255254
12186.131.120.0/2486.131.120.1 to 86.131.120.25486.131.120.255254
12286.131.121.0/2486.131.121.1 to 86.131.121.25486.131.121.255254
12386.131.122.0/2486.131.122.1 to 86.131.122.25486.131.122.255254
12486.131.123.0/2486.131.123.1 to 86.131.123.25486.131.123.255254
12586.131.124.0/2486.131.124.1 to 86.131.124.25486.131.124.255254
12686.131.125.0/2486.131.125.1 to 86.131.125.25486.131.125.255254
12786.131.126.0/2486.131.126.1 to 86.131.126.25486.131.126.255254
12886.131.127.0/2486.131.127.1 to 86.131.127.25486.131.127.255254
12986.131.128.0/2486.131.128.1 to 86.131.128.25486.131.128.255254
13086.131.129.0/2486.131.129.1 to 86.131.129.25486.131.129.255254
13186.131.130.0/2486.131.130.1 to 86.131.130.25486.131.130.255254
13286.131.131.0/2486.131.131.1 to 86.131.131.25486.131.131.255254
13386.131.132.0/2486.131.132.1 to 86.131.132.25486.131.132.255254
13486.131.133.0/2486.131.133.1 to 86.131.133.25486.131.133.255254
13586.131.134.0/2486.131.134.1 to 86.131.134.25486.131.134.255254
13686.131.135.0/2486.131.135.1 to 86.131.135.25486.131.135.255254
13786.131.136.0/2486.131.136.1 to 86.131.136.25486.131.136.255254
13886.131.137.0/2486.131.137.1 to 86.131.137.25486.131.137.255254
13986.131.138.0/2486.131.138.1 to 86.131.138.25486.131.138.255254
14086.131.139.0/2486.131.139.1 to 86.131.139.25486.131.139.255254
14186.131.140.0/2486.131.140.1 to 86.131.140.25486.131.140.255254
14286.131.141.0/2486.131.141.1 to 86.131.141.25486.131.141.255254
14386.131.142.0/2486.131.142.1 to 86.131.142.25486.131.142.255254
14486.131.143.0/2486.131.143.1 to 86.131.143.25486.131.143.255254
14586.131.144.0/2486.131.144.1 to 86.131.144.25486.131.144.255254
14686.131.145.0/2486.131.145.1 to 86.131.145.25486.131.145.255254
14786.131.146.0/2486.131.146.1 to 86.131.146.25486.131.146.255254
14886.131.147.0/2486.131.147.1 to 86.131.147.25486.131.147.255254
14986.131.148.0/2486.131.148.1 to 86.131.148.25486.131.148.255254
15086.131.149.0/2486.131.149.1 to 86.131.149.25486.131.149.255254
15186.131.150.0/2486.131.150.1 to 86.131.150.25486.131.150.255254
15286.131.151.0/2486.131.151.1 to 86.131.151.25486.131.151.255254
15386.131.152.0/2486.131.152.1 to 86.131.152.25486.131.152.255254
15486.131.153.0/2486.131.153.1 to 86.131.153.25486.131.153.255254
15586.131.154.0/2486.131.154.1 to 86.131.154.25486.131.154.255254
15686.131.155.0/2486.131.155.1 to 86.131.155.25486.131.155.255254
15786.131.156.0/2486.131.156.1 to 86.131.156.25486.131.156.255254
15886.131.157.0/2486.131.157.1 to 86.131.157.25486.131.157.255254
15986.131.158.0/2486.131.158.1 to 86.131.158.25486.131.158.255254
16086.131.159.0/2486.131.159.1 to 86.131.159.25486.131.159.255254
16186.131.160.0/2486.131.160.1 to 86.131.160.25486.131.160.255254
16286.131.161.0/2486.131.161.1 to 86.131.161.25486.131.161.255254
16386.131.162.0/2486.131.162.1 to 86.131.162.25486.131.162.255254
16486.131.163.0/2486.131.163.1 to 86.131.163.25486.131.163.255254
16586.131.164.0/2486.131.164.1 to 86.131.164.25486.131.164.255254
16686.131.165.0/2486.131.165.1 to 86.131.165.25486.131.165.255254
16786.131.166.0/2486.131.166.1 to 86.131.166.25486.131.166.255254
16886.131.167.0/2486.131.167.1 to 86.131.167.25486.131.167.255254
16986.131.168.0/2486.131.168.1 to 86.131.168.25486.131.168.255254
17086.131.169.0/2486.131.169.1 to 86.131.169.25486.131.169.255254
17186.131.170.0/2486.131.170.1 to 86.131.170.25486.131.170.255254
17286.131.171.0/2486.131.171.1 to 86.131.171.25486.131.171.255254
17386.131.172.0/2486.131.172.1 to 86.131.172.25486.131.172.255254
17486.131.173.0/2486.131.173.1 to 86.131.173.25486.131.173.255254
17586.131.174.0/2486.131.174.1 to 86.131.174.25486.131.174.255254
17686.131.175.0/2486.131.175.1 to 86.131.175.25486.131.175.255254
17786.131.176.0/2486.131.176.1 to 86.131.176.25486.131.176.255254
17886.131.177.0/2486.131.177.1 to 86.131.177.25486.131.177.255254
17986.131.178.0/2486.131.178.1 to 86.131.178.25486.131.178.255254
18086.131.179.0/2486.131.179.1 to 86.131.179.25486.131.179.255254
18186.131.180.0/2486.131.180.1 to 86.131.180.25486.131.180.255254
18286.131.181.0/2486.131.181.1 to 86.131.181.25486.131.181.255254
18386.131.182.0/2486.131.182.1 to 86.131.182.25486.131.182.255254
18486.131.183.0/2486.131.183.1 to 86.131.183.25486.131.183.255254
18586.131.184.0/2486.131.184.1 to 86.131.184.25486.131.184.255254
18686.131.185.0/2486.131.185.1 to 86.131.185.25486.131.185.255254
18786.131.186.0/2486.131.186.1 to 86.131.186.25486.131.186.255254
18886.131.187.0/2486.131.187.1 to 86.131.187.25486.131.187.255254
18986.131.188.0/2486.131.188.1 to 86.131.188.25486.131.188.255254
19086.131.189.0/2486.131.189.1 to 86.131.189.25486.131.189.255254
19186.131.190.0/2486.131.190.1 to 86.131.190.25486.131.190.255254
19286.131.191.0/2486.131.191.1 to 86.131.191.25486.131.191.255254
19386.131.192.0/2486.131.192.1 to 86.131.192.25486.131.192.255254
19486.131.193.0/2486.131.193.1 to 86.131.193.25486.131.193.255254
19586.131.194.0/2486.131.194.1 to 86.131.194.25486.131.194.255254
19686.131.195.0/2486.131.195.1 to 86.131.195.25486.131.195.255254
19786.131.196.0/2486.131.196.1 to 86.131.196.25486.131.196.255254
19886.131.197.0/2486.131.197.1 to 86.131.197.25486.131.197.255254
19986.131.198.0/2486.131.198.1 to 86.131.198.25486.131.198.255254
20086.131.199.0/2486.131.199.1 to 86.131.199.25486.131.199.255254
20186.131.200.0/2486.131.200.1 to 86.131.200.25486.131.200.255254
20286.131.201.0/2486.131.201.1 to 86.131.201.25486.131.201.255254
20386.131.202.0/2486.131.202.1 to 86.131.202.25486.131.202.255254
20486.131.203.0/2486.131.203.1 to 86.131.203.25486.131.203.255254
20586.131.204.0/2486.131.204.1 to 86.131.204.25486.131.204.255254
20686.131.205.0/2486.131.205.1 to 86.131.205.25486.131.205.255254
20786.131.206.0/2486.131.206.1 to 86.131.206.25486.131.206.255254
20886.131.207.0/2486.131.207.1 to 86.131.207.25486.131.207.255254
20986.131.208.0/2486.131.208.1 to 86.131.208.25486.131.208.255254
21086.131.209.0/2486.131.209.1 to 86.131.209.25486.131.209.255254
21186.131.210.0/2486.131.210.1 to 86.131.210.25486.131.210.255254
21286.131.211.0/2486.131.211.1 to 86.131.211.25486.131.211.255254
21386.131.212.0/2486.131.212.1 to 86.131.212.25486.131.212.255254
21486.131.213.0/2486.131.213.1 to 86.131.213.25486.131.213.255254
21586.131.214.0/2486.131.214.1 to 86.131.214.25486.131.214.255254
21686.131.215.0/2486.131.215.1 to 86.131.215.25486.131.215.255254
21786.131.216.0/2486.131.216.1 to 86.131.216.25486.131.216.255254
21886.131.217.0/2486.131.217.1 to 86.131.217.25486.131.217.255254
21986.131.218.0/2486.131.218.1 to 86.131.218.25486.131.218.255254
22086.131.219.0/2486.131.219.1 to 86.131.219.25486.131.219.255254
22186.131.220.0/2486.131.220.1 to 86.131.220.25486.131.220.255254
22286.131.221.0/2486.131.221.1 to 86.131.221.25486.131.221.255254
22386.131.222.0/2486.131.222.1 to 86.131.222.25486.131.222.255254
22486.131.223.0/2486.131.223.1 to 86.131.223.25486.131.223.255254
22586.131.224.0/2486.131.224.1 to 86.131.224.25486.131.224.255254
22686.131.225.0/2486.131.225.1 to 86.131.225.25486.131.225.255254
22786.131.226.0/2486.131.226.1 to 86.131.226.25486.131.226.255254
22886.131.227.0/2486.131.227.1 to 86.131.227.25486.131.227.255254
22986.131.228.0/2486.131.228.1 to 86.131.228.25486.131.228.255254
23086.131.229.0/2486.131.229.1 to 86.131.229.25486.131.229.255254
23186.131.230.0/2486.131.230.1 to 86.131.230.25486.131.230.255254
23286.131.231.0/2486.131.231.1 to 86.131.231.25486.131.231.255254
23386.131.232.0/2486.131.232.1 to 86.131.232.25486.131.232.255254
23486.131.233.0/2486.131.233.1 to 86.131.233.25486.131.233.255254
23586.131.234.0/2486.131.234.1 to 86.131.234.25486.131.234.255254
23686.131.235.0/2486.131.235.1 to 86.131.235.25486.131.235.255254
23786.131.236.0/2486.131.236.1 to 86.131.236.25486.131.236.255254
23886.131.237.0/2486.131.237.1 to 86.131.237.25486.131.237.255254
23986.131.238.0/2486.131.238.1 to 86.131.238.25486.131.238.255254
24086.131.239.0/2486.131.239.1 to 86.131.239.25486.131.239.255254
24186.131.240.0/2486.131.240.1 to 86.131.240.25486.131.240.255254
24286.131.241.0/2486.131.241.1 to 86.131.241.25486.131.241.255254
24386.131.242.0/2486.131.242.1 to 86.131.242.25486.131.242.255254
24486.131.243.0/2486.131.243.1 to 86.131.243.25486.131.243.255254
24586.131.244.0/2486.131.244.1 to 86.131.244.25486.131.244.255254
24686.131.245.0/2486.131.245.1 to 86.131.245.25486.131.245.255254
24786.131.246.0/2486.131.246.1 to 86.131.246.25486.131.246.255254
24886.131.247.0/2486.131.247.1 to 86.131.247.25486.131.247.255254
24986.131.248.0/2486.131.248.1 to 86.131.248.25486.131.248.255254
25086.131.249.0/2486.131.249.1 to 86.131.249.25486.131.249.255254
25186.131.250.0/2486.131.250.1 to 86.131.250.25486.131.250.255254
25286.131.251.0/2486.131.251.1 to 86.131.251.25486.131.251.255254
25386.131.252.0/2486.131.252.1 to 86.131.252.25486.131.252.255254
25486.131.253.0/2486.131.253.1 to 86.131.253.25486.131.253.255254
25586.131.254.0/2486.131.254.1 to 86.131.254.25486.131.254.255254
25686.131.255.0/2486.131.255.1 to 86.131.255.25486.131.255.255254

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