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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.

Network86.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
86.0.0.0
Broadcast address
87.255.255.255
First usable
86.0.0.1
Last usable
87.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
A (default /8)
As numbers
Hex 56000000 · Integer 1442840576 to 1476395007
Reverse DNS zones
86.in-addr.arpa
87.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010110.00000000.00000000.0000000086.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network01010110.00000000.00000000.0000000086.0.0.0
Broadcast01010111.11111111.11111111.1111111187.255.255.255
Split into smaller subnets/16
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

86.0.0.0/7 makes 512 subnets of /16; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
186.0.0.0/1686.0.0.1 to 86.0.255.25486.0.255.25565,534
286.1.0.0/1686.1.0.1 to 86.1.255.25486.1.255.25565,534
386.2.0.0/1686.2.0.1 to 86.2.255.25486.2.255.25565,534
486.3.0.0/1686.3.0.1 to 86.3.255.25486.3.255.25565,534
586.4.0.0/1686.4.0.1 to 86.4.255.25486.4.255.25565,534
686.5.0.0/1686.5.0.1 to 86.5.255.25486.5.255.25565,534
786.6.0.0/1686.6.0.1 to 86.6.255.25486.6.255.25565,534
886.7.0.0/1686.7.0.1 to 86.7.255.25486.7.255.25565,534
986.8.0.0/1686.8.0.1 to 86.8.255.25486.8.255.25565,534
1086.9.0.0/1686.9.0.1 to 86.9.255.25486.9.255.25565,534
1186.10.0.0/1686.10.0.1 to 86.10.255.25486.10.255.25565,534
1286.11.0.0/1686.11.0.1 to 86.11.255.25486.11.255.25565,534
1386.12.0.0/1686.12.0.1 to 86.12.255.25486.12.255.25565,534
1486.13.0.0/1686.13.0.1 to 86.13.255.25486.13.255.25565,534
1586.14.0.0/1686.14.0.1 to 86.14.255.25486.14.255.25565,534
1686.15.0.0/1686.15.0.1 to 86.15.255.25486.15.255.25565,534
1786.16.0.0/1686.16.0.1 to 86.16.255.25486.16.255.25565,534
1886.17.0.0/1686.17.0.1 to 86.17.255.25486.17.255.25565,534
1986.18.0.0/1686.18.0.1 to 86.18.255.25486.18.255.25565,534
2086.19.0.0/1686.19.0.1 to 86.19.255.25486.19.255.25565,534
2186.20.0.0/1686.20.0.1 to 86.20.255.25486.20.255.25565,534
2286.21.0.0/1686.21.0.1 to 86.21.255.25486.21.255.25565,534
2386.22.0.0/1686.22.0.1 to 86.22.255.25486.22.255.25565,534
2486.23.0.0/1686.23.0.1 to 86.23.255.25486.23.255.25565,534
2586.24.0.0/1686.24.0.1 to 86.24.255.25486.24.255.25565,534
2686.25.0.0/1686.25.0.1 to 86.25.255.25486.25.255.25565,534
2786.26.0.0/1686.26.0.1 to 86.26.255.25486.26.255.25565,534
2886.27.0.0/1686.27.0.1 to 86.27.255.25486.27.255.25565,534
2986.28.0.0/1686.28.0.1 to 86.28.255.25486.28.255.25565,534
3086.29.0.0/1686.29.0.1 to 86.29.255.25486.29.255.25565,534
3186.30.0.0/1686.30.0.1 to 86.30.255.25486.30.255.25565,534
3286.31.0.0/1686.31.0.1 to 86.31.255.25486.31.255.25565,534
3386.32.0.0/1686.32.0.1 to 86.32.255.25486.32.255.25565,534
3486.33.0.0/1686.33.0.1 to 86.33.255.25486.33.255.25565,534
3586.34.0.0/1686.34.0.1 to 86.34.255.25486.34.255.25565,534
3686.35.0.0/1686.35.0.1 to 86.35.255.25486.35.255.25565,534
3786.36.0.0/1686.36.0.1 to 86.36.255.25486.36.255.25565,534
3886.37.0.0/1686.37.0.1 to 86.37.255.25486.37.255.25565,534
3986.38.0.0/1686.38.0.1 to 86.38.255.25486.38.255.25565,534
4086.39.0.0/1686.39.0.1 to 86.39.255.25486.39.255.25565,534
4186.40.0.0/1686.40.0.1 to 86.40.255.25486.40.255.25565,534
4286.41.0.0/1686.41.0.1 to 86.41.255.25486.41.255.25565,534
4386.42.0.0/1686.42.0.1 to 86.42.255.25486.42.255.25565,534
4486.43.0.0/1686.43.0.1 to 86.43.255.25486.43.255.25565,534
4586.44.0.0/1686.44.0.1 to 86.44.255.25486.44.255.25565,534
4686.45.0.0/1686.45.0.1 to 86.45.255.25486.45.255.25565,534
4786.46.0.0/1686.46.0.1 to 86.46.255.25486.46.255.25565,534
4886.47.0.0/1686.47.0.1 to 86.47.255.25486.47.255.25565,534
4986.48.0.0/1686.48.0.1 to 86.48.255.25486.48.255.25565,534
5086.49.0.0/1686.49.0.1 to 86.49.255.25486.49.255.25565,534
5186.50.0.0/1686.50.0.1 to 86.50.255.25486.50.255.25565,534
5286.51.0.0/1686.51.0.1 to 86.51.255.25486.51.255.25565,534
5386.52.0.0/1686.52.0.1 to 86.52.255.25486.52.255.25565,534
5486.53.0.0/1686.53.0.1 to 86.53.255.25486.53.255.25565,534
5586.54.0.0/1686.54.0.1 to 86.54.255.25486.54.255.25565,534
5686.55.0.0/1686.55.0.1 to 86.55.255.25486.55.255.25565,534
5786.56.0.0/1686.56.0.1 to 86.56.255.25486.56.255.25565,534
5886.57.0.0/1686.57.0.1 to 86.57.255.25486.57.255.25565,534
5986.58.0.0/1686.58.0.1 to 86.58.255.25486.58.255.25565,534
6086.59.0.0/1686.59.0.1 to 86.59.255.25486.59.255.25565,534
6186.60.0.0/1686.60.0.1 to 86.60.255.25486.60.255.25565,534
6286.61.0.0/1686.61.0.1 to 86.61.255.25486.61.255.25565,534
6386.62.0.0/1686.62.0.1 to 86.62.255.25486.62.255.25565,534
6486.63.0.0/1686.63.0.1 to 86.63.255.25486.63.255.25565,534
6586.64.0.0/1686.64.0.1 to 86.64.255.25486.64.255.25565,534
6686.65.0.0/1686.65.0.1 to 86.65.255.25486.65.255.25565,534
6786.66.0.0/1686.66.0.1 to 86.66.255.25486.66.255.25565,534
6886.67.0.0/1686.67.0.1 to 86.67.255.25486.67.255.25565,534
6986.68.0.0/1686.68.0.1 to 86.68.255.25486.68.255.25565,534
7086.69.0.0/1686.69.0.1 to 86.69.255.25486.69.255.25565,534
7186.70.0.0/1686.70.0.1 to 86.70.255.25486.70.255.25565,534
7286.71.0.0/1686.71.0.1 to 86.71.255.25486.71.255.25565,534
7386.72.0.0/1686.72.0.1 to 86.72.255.25486.72.255.25565,534
7486.73.0.0/1686.73.0.1 to 86.73.255.25486.73.255.25565,534
7586.74.0.0/1686.74.0.1 to 86.74.255.25486.74.255.25565,534
7686.75.0.0/1686.75.0.1 to 86.75.255.25486.75.255.25565,534
7786.76.0.0/1686.76.0.1 to 86.76.255.25486.76.255.25565,534
7886.77.0.0/1686.77.0.1 to 86.77.255.25486.77.255.25565,534
7986.78.0.0/1686.78.0.1 to 86.78.255.25486.78.255.25565,534
8086.79.0.0/1686.79.0.1 to 86.79.255.25486.79.255.25565,534
8186.80.0.0/1686.80.0.1 to 86.80.255.25486.80.255.25565,534
8286.81.0.0/1686.81.0.1 to 86.81.255.25486.81.255.25565,534
8386.82.0.0/1686.82.0.1 to 86.82.255.25486.82.255.25565,534
8486.83.0.0/1686.83.0.1 to 86.83.255.25486.83.255.25565,534
8586.84.0.0/1686.84.0.1 to 86.84.255.25486.84.255.25565,534
8686.85.0.0/1686.85.0.1 to 86.85.255.25486.85.255.25565,534
8786.86.0.0/1686.86.0.1 to 86.86.255.25486.86.255.25565,534
8886.87.0.0/1686.87.0.1 to 86.87.255.25486.87.255.25565,534
8986.88.0.0/1686.88.0.1 to 86.88.255.25486.88.255.25565,534
9086.89.0.0/1686.89.0.1 to 86.89.255.25486.89.255.25565,534
9186.90.0.0/1686.90.0.1 to 86.90.255.25486.90.255.25565,534
9286.91.0.0/1686.91.0.1 to 86.91.255.25486.91.255.25565,534
9386.92.0.0/1686.92.0.1 to 86.92.255.25486.92.255.25565,534
9486.93.0.0/1686.93.0.1 to 86.93.255.25486.93.255.25565,534
9586.94.0.0/1686.94.0.1 to 86.94.255.25486.94.255.25565,534
9686.95.0.0/1686.95.0.1 to 86.95.255.25486.95.255.25565,534
9786.96.0.0/1686.96.0.1 to 86.96.255.25486.96.255.25565,534
9886.97.0.0/1686.97.0.1 to 86.97.255.25486.97.255.25565,534
9986.98.0.0/1686.98.0.1 to 86.98.255.25486.98.255.25565,534
10086.99.0.0/1686.99.0.1 to 86.99.255.25486.99.255.25565,534
10186.100.0.0/1686.100.0.1 to 86.100.255.25486.100.255.25565,534
10286.101.0.0/1686.101.0.1 to 86.101.255.25486.101.255.25565,534
10386.102.0.0/1686.102.0.1 to 86.102.255.25486.102.255.25565,534
10486.103.0.0/1686.103.0.1 to 86.103.255.25486.103.255.25565,534
10586.104.0.0/1686.104.0.1 to 86.104.255.25486.104.255.25565,534
10686.105.0.0/1686.105.0.1 to 86.105.255.25486.105.255.25565,534
10786.106.0.0/1686.106.0.1 to 86.106.255.25486.106.255.25565,534
10886.107.0.0/1686.107.0.1 to 86.107.255.25486.107.255.25565,534
10986.108.0.0/1686.108.0.1 to 86.108.255.25486.108.255.25565,534
11086.109.0.0/1686.109.0.1 to 86.109.255.25486.109.255.25565,534
11186.110.0.0/1686.110.0.1 to 86.110.255.25486.110.255.25565,534
11286.111.0.0/1686.111.0.1 to 86.111.255.25486.111.255.25565,534
11386.112.0.0/1686.112.0.1 to 86.112.255.25486.112.255.25565,534
11486.113.0.0/1686.113.0.1 to 86.113.255.25486.113.255.25565,534
11586.114.0.0/1686.114.0.1 to 86.114.255.25486.114.255.25565,534
11686.115.0.0/1686.115.0.1 to 86.115.255.25486.115.255.25565,534
11786.116.0.0/1686.116.0.1 to 86.116.255.25486.116.255.25565,534
11886.117.0.0/1686.117.0.1 to 86.117.255.25486.117.255.25565,534
11986.118.0.0/1686.118.0.1 to 86.118.255.25486.118.255.25565,534
12086.119.0.0/1686.119.0.1 to 86.119.255.25486.119.255.25565,534
12186.120.0.0/1686.120.0.1 to 86.120.255.25486.120.255.25565,534
12286.121.0.0/1686.121.0.1 to 86.121.255.25486.121.255.25565,534
12386.122.0.0/1686.122.0.1 to 86.122.255.25486.122.255.25565,534
12486.123.0.0/1686.123.0.1 to 86.123.255.25486.123.255.25565,534
12586.124.0.0/1686.124.0.1 to 86.124.255.25486.124.255.25565,534
12686.125.0.0/1686.125.0.1 to 86.125.255.25486.125.255.25565,534
12786.126.0.0/1686.126.0.1 to 86.126.255.25486.126.255.25565,534
12886.127.0.0/1686.127.0.1 to 86.127.255.25486.127.255.25565,534
12986.128.0.0/1686.128.0.1 to 86.128.255.25486.128.255.25565,534
13086.129.0.0/1686.129.0.1 to 86.129.255.25486.129.255.25565,534
13186.130.0.0/1686.130.0.1 to 86.130.255.25486.130.255.25565,534
13286.131.0.0/1686.131.0.1 to 86.131.255.25486.131.255.25565,534
13386.132.0.0/1686.132.0.1 to 86.132.255.25486.132.255.25565,534
13486.133.0.0/1686.133.0.1 to 86.133.255.25486.133.255.25565,534
13586.134.0.0/1686.134.0.1 to 86.134.255.25486.134.255.25565,534
13686.135.0.0/1686.135.0.1 to 86.135.255.25486.135.255.25565,534
13786.136.0.0/1686.136.0.1 to 86.136.255.25486.136.255.25565,534
13886.137.0.0/1686.137.0.1 to 86.137.255.25486.137.255.25565,534
13986.138.0.0/1686.138.0.1 to 86.138.255.25486.138.255.25565,534
14086.139.0.0/1686.139.0.1 to 86.139.255.25486.139.255.25565,534
14186.140.0.0/1686.140.0.1 to 86.140.255.25486.140.255.25565,534
14286.141.0.0/1686.141.0.1 to 86.141.255.25486.141.255.25565,534
14386.142.0.0/1686.142.0.1 to 86.142.255.25486.142.255.25565,534
14486.143.0.0/1686.143.0.1 to 86.143.255.25486.143.255.25565,534
14586.144.0.0/1686.144.0.1 to 86.144.255.25486.144.255.25565,534
14686.145.0.0/1686.145.0.1 to 86.145.255.25486.145.255.25565,534
14786.146.0.0/1686.146.0.1 to 86.146.255.25486.146.255.25565,534
14886.147.0.0/1686.147.0.1 to 86.147.255.25486.147.255.25565,534
14986.148.0.0/1686.148.0.1 to 86.148.255.25486.148.255.25565,534
15086.149.0.0/1686.149.0.1 to 86.149.255.25486.149.255.25565,534
15186.150.0.0/1686.150.0.1 to 86.150.255.25486.150.255.25565,534
15286.151.0.0/1686.151.0.1 to 86.151.255.25486.151.255.25565,534
15386.152.0.0/1686.152.0.1 to 86.152.255.25486.152.255.25565,534
15486.153.0.0/1686.153.0.1 to 86.153.255.25486.153.255.25565,534
15586.154.0.0/1686.154.0.1 to 86.154.255.25486.154.255.25565,534
15686.155.0.0/1686.155.0.1 to 86.155.255.25486.155.255.25565,534
15786.156.0.0/1686.156.0.1 to 86.156.255.25486.156.255.25565,534
15886.157.0.0/1686.157.0.1 to 86.157.255.25486.157.255.25565,534
15986.158.0.0/1686.158.0.1 to 86.158.255.25486.158.255.25565,534
16086.159.0.0/1686.159.0.1 to 86.159.255.25486.159.255.25565,534
16186.160.0.0/1686.160.0.1 to 86.160.255.25486.160.255.25565,534
16286.161.0.0/1686.161.0.1 to 86.161.255.25486.161.255.25565,534
16386.162.0.0/1686.162.0.1 to 86.162.255.25486.162.255.25565,534
16486.163.0.0/1686.163.0.1 to 86.163.255.25486.163.255.25565,534
16586.164.0.0/1686.164.0.1 to 86.164.255.25486.164.255.25565,534
16686.165.0.0/1686.165.0.1 to 86.165.255.25486.165.255.25565,534
16786.166.0.0/1686.166.0.1 to 86.166.255.25486.166.255.25565,534
16886.167.0.0/1686.167.0.1 to 86.167.255.25486.167.255.25565,534
16986.168.0.0/1686.168.0.1 to 86.168.255.25486.168.255.25565,534
17086.169.0.0/1686.169.0.1 to 86.169.255.25486.169.255.25565,534
17186.170.0.0/1686.170.0.1 to 86.170.255.25486.170.255.25565,534
17286.171.0.0/1686.171.0.1 to 86.171.255.25486.171.255.25565,534
17386.172.0.0/1686.172.0.1 to 86.172.255.25486.172.255.25565,534
17486.173.0.0/1686.173.0.1 to 86.173.255.25486.173.255.25565,534
17586.174.0.0/1686.174.0.1 to 86.174.255.25486.174.255.25565,534
17686.175.0.0/1686.175.0.1 to 86.175.255.25486.175.255.25565,534
17786.176.0.0/1686.176.0.1 to 86.176.255.25486.176.255.25565,534
17886.177.0.0/1686.177.0.1 to 86.177.255.25486.177.255.25565,534
17986.178.0.0/1686.178.0.1 to 86.178.255.25486.178.255.25565,534
18086.179.0.0/1686.179.0.1 to 86.179.255.25486.179.255.25565,534
18186.180.0.0/1686.180.0.1 to 86.180.255.25486.180.255.25565,534
18286.181.0.0/1686.181.0.1 to 86.181.255.25486.181.255.25565,534
18386.182.0.0/1686.182.0.1 to 86.182.255.25486.182.255.25565,534
18486.183.0.0/1686.183.0.1 to 86.183.255.25486.183.255.25565,534
18586.184.0.0/1686.184.0.1 to 86.184.255.25486.184.255.25565,534
18686.185.0.0/1686.185.0.1 to 86.185.255.25486.185.255.25565,534
18786.186.0.0/1686.186.0.1 to 86.186.255.25486.186.255.25565,534
18886.187.0.0/1686.187.0.1 to 86.187.255.25486.187.255.25565,534
18986.188.0.0/1686.188.0.1 to 86.188.255.25486.188.255.25565,534
19086.189.0.0/1686.189.0.1 to 86.189.255.25486.189.255.25565,534
19186.190.0.0/1686.190.0.1 to 86.190.255.25486.190.255.25565,534
19286.191.0.0/1686.191.0.1 to 86.191.255.25486.191.255.25565,534
19386.192.0.0/1686.192.0.1 to 86.192.255.25486.192.255.25565,534
19486.193.0.0/1686.193.0.1 to 86.193.255.25486.193.255.25565,534
19586.194.0.0/1686.194.0.1 to 86.194.255.25486.194.255.25565,534
19686.195.0.0/1686.195.0.1 to 86.195.255.25486.195.255.25565,534
19786.196.0.0/1686.196.0.1 to 86.196.255.25486.196.255.25565,534
19886.197.0.0/1686.197.0.1 to 86.197.255.25486.197.255.25565,534
19986.198.0.0/1686.198.0.1 to 86.198.255.25486.198.255.25565,534
20086.199.0.0/1686.199.0.1 to 86.199.255.25486.199.255.25565,534
20186.200.0.0/1686.200.0.1 to 86.200.255.25486.200.255.25565,534
20286.201.0.0/1686.201.0.1 to 86.201.255.25486.201.255.25565,534
20386.202.0.0/1686.202.0.1 to 86.202.255.25486.202.255.25565,534
20486.203.0.0/1686.203.0.1 to 86.203.255.25486.203.255.25565,534
20586.204.0.0/1686.204.0.1 to 86.204.255.25486.204.255.25565,534
20686.205.0.0/1686.205.0.1 to 86.205.255.25486.205.255.25565,534
20786.206.0.0/1686.206.0.1 to 86.206.255.25486.206.255.25565,534
20886.207.0.0/1686.207.0.1 to 86.207.255.25486.207.255.25565,534
20986.208.0.0/1686.208.0.1 to 86.208.255.25486.208.255.25565,534
21086.209.0.0/1686.209.0.1 to 86.209.255.25486.209.255.25565,534
21186.210.0.0/1686.210.0.1 to 86.210.255.25486.210.255.25565,534
21286.211.0.0/1686.211.0.1 to 86.211.255.25486.211.255.25565,534
21386.212.0.0/1686.212.0.1 to 86.212.255.25486.212.255.25565,534
21486.213.0.0/1686.213.0.1 to 86.213.255.25486.213.255.25565,534
21586.214.0.0/1686.214.0.1 to 86.214.255.25486.214.255.25565,534
21686.215.0.0/1686.215.0.1 to 86.215.255.25486.215.255.25565,534
21786.216.0.0/1686.216.0.1 to 86.216.255.25486.216.255.25565,534
21886.217.0.0/1686.217.0.1 to 86.217.255.25486.217.255.25565,534
21986.218.0.0/1686.218.0.1 to 86.218.255.25486.218.255.25565,534
22086.219.0.0/1686.219.0.1 to 86.219.255.25486.219.255.25565,534
22186.220.0.0/1686.220.0.1 to 86.220.255.25486.220.255.25565,534
22286.221.0.0/1686.221.0.1 to 86.221.255.25486.221.255.25565,534
22386.222.0.0/1686.222.0.1 to 86.222.255.25486.222.255.25565,534
22486.223.0.0/1686.223.0.1 to 86.223.255.25486.223.255.25565,534
22586.224.0.0/1686.224.0.1 to 86.224.255.25486.224.255.25565,534
22686.225.0.0/1686.225.0.1 to 86.225.255.25486.225.255.25565,534
22786.226.0.0/1686.226.0.1 to 86.226.255.25486.226.255.25565,534
22886.227.0.0/1686.227.0.1 to 86.227.255.25486.227.255.25565,534
22986.228.0.0/1686.228.0.1 to 86.228.255.25486.228.255.25565,534
23086.229.0.0/1686.229.0.1 to 86.229.255.25486.229.255.25565,534
23186.230.0.0/1686.230.0.1 to 86.230.255.25486.230.255.25565,534
23286.231.0.0/1686.231.0.1 to 86.231.255.25486.231.255.25565,534
23386.232.0.0/1686.232.0.1 to 86.232.255.25486.232.255.25565,534
23486.233.0.0/1686.233.0.1 to 86.233.255.25486.233.255.25565,534
23586.234.0.0/1686.234.0.1 to 86.234.255.25486.234.255.25565,534
23686.235.0.0/1686.235.0.1 to 86.235.255.25486.235.255.25565,534
23786.236.0.0/1686.236.0.1 to 86.236.255.25486.236.255.25565,534
23886.237.0.0/1686.237.0.1 to 86.237.255.25486.237.255.25565,534
23986.238.0.0/1686.238.0.1 to 86.238.255.25486.238.255.25565,534
24086.239.0.0/1686.239.0.1 to 86.239.255.25486.239.255.25565,534
24186.240.0.0/1686.240.0.1 to 86.240.255.25486.240.255.25565,534
24286.241.0.0/1686.241.0.1 to 86.241.255.25486.241.255.25565,534
24386.242.0.0/1686.242.0.1 to 86.242.255.25486.242.255.25565,534
24486.243.0.0/1686.243.0.1 to 86.243.255.25486.243.255.25565,534
24586.244.0.0/1686.244.0.1 to 86.244.255.25486.244.255.25565,534
24686.245.0.0/1686.245.0.1 to 86.245.255.25486.245.255.25565,534
24786.246.0.0/1686.246.0.1 to 86.246.255.25486.246.255.25565,534
24886.247.0.0/1686.247.0.1 to 86.247.255.25486.247.255.25565,534
24986.248.0.0/1686.248.0.1 to 86.248.255.25486.248.255.25565,534
25086.249.0.0/1686.249.0.1 to 86.249.255.25486.249.255.25565,534
25186.250.0.0/1686.250.0.1 to 86.250.255.25486.250.255.25565,534
25286.251.0.0/1686.251.0.1 to 86.251.255.25486.251.255.25565,534
25386.252.0.0/1686.252.0.1 to 86.252.255.25486.252.255.25565,534
25486.253.0.0/1686.253.0.1 to 86.253.255.25486.253.255.25565,534
25586.254.0.0/1686.254.0.1 to 86.254.255.25486.254.255.25565,534
25686.255.0.0/1686.255.0.1 to 86.255.255.25486.255.255.25565,534

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.