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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.

Network84.0.0.0/6
Usable hosts67,108,862
Subnet mask252.0.0.0
Addresses67,108,864
Network address
84.0.0.0
Broadcast address
87.255.255.255
First usable
84.0.0.1
Last usable
87.255.255.254
Usable hosts
67,108,862 (67,108,864 less the network and broadcast addresses)
Subnet mask
252.0.0.0
Wildcard mask
3.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/6
Type
Public public
Old class
A (default /8)
As numbers
Hex 54000000 · Integer 1409286144 to 1476395007
Reverse DNS zones
84.in-addr.arpa
85.in-addr.arpa
86.in-addr.arpa
87.in-addr.arpa
/6 is not on a 8-bit boundary, so it takes 4 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010100.00000000.00000000.0000000084.0.0.0
Subnet mask11111100.00000000.00000000.00000000252.0.0.0
Network01010100.00000000.00000000.0000000084.0.0.0
Broadcast01010111.11111111.11111111.1111111187.255.255.255
Split into smaller subnets/14
/7 (2)/8 (4)/9 (8)/10 (16)/11 (32)/12 (64)/13 (128)/14 (256)/15 (512)/16 (1,024)/17 (2,048)/18 (4,096)

84.0.0.0/6 makes 256 subnets of /14.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
184.0.0.0/1484.0.0.1 to 84.3.255.25484.3.255.255262,142
284.4.0.0/1484.4.0.1 to 84.7.255.25484.7.255.255262,142
384.8.0.0/1484.8.0.1 to 84.11.255.25484.11.255.255262,142
484.12.0.0/1484.12.0.1 to 84.15.255.25484.15.255.255262,142
584.16.0.0/1484.16.0.1 to 84.19.255.25484.19.255.255262,142
684.20.0.0/1484.20.0.1 to 84.23.255.25484.23.255.255262,142
784.24.0.0/1484.24.0.1 to 84.27.255.25484.27.255.255262,142
884.28.0.0/1484.28.0.1 to 84.31.255.25484.31.255.255262,142
984.32.0.0/1484.32.0.1 to 84.35.255.25484.35.255.255262,142
1084.36.0.0/1484.36.0.1 to 84.39.255.25484.39.255.255262,142
1184.40.0.0/1484.40.0.1 to 84.43.255.25484.43.255.255262,142
1284.44.0.0/1484.44.0.1 to 84.47.255.25484.47.255.255262,142
1384.48.0.0/1484.48.0.1 to 84.51.255.25484.51.255.255262,142
1484.52.0.0/1484.52.0.1 to 84.55.255.25484.55.255.255262,142
1584.56.0.0/1484.56.0.1 to 84.59.255.25484.59.255.255262,142
1684.60.0.0/1484.60.0.1 to 84.63.255.25484.63.255.255262,142
1784.64.0.0/1484.64.0.1 to 84.67.255.25484.67.255.255262,142
1884.68.0.0/1484.68.0.1 to 84.71.255.25484.71.255.255262,142
1984.72.0.0/1484.72.0.1 to 84.75.255.25484.75.255.255262,142
2084.76.0.0/1484.76.0.1 to 84.79.255.25484.79.255.255262,142
2184.80.0.0/1484.80.0.1 to 84.83.255.25484.83.255.255262,142
2284.84.0.0/1484.84.0.1 to 84.87.255.25484.87.255.255262,142
2384.88.0.0/1484.88.0.1 to 84.91.255.25484.91.255.255262,142
2484.92.0.0/1484.92.0.1 to 84.95.255.25484.95.255.255262,142
2584.96.0.0/1484.96.0.1 to 84.99.255.25484.99.255.255262,142
2684.100.0.0/1484.100.0.1 to 84.103.255.25484.103.255.255262,142
2784.104.0.0/1484.104.0.1 to 84.107.255.25484.107.255.255262,142
2884.108.0.0/1484.108.0.1 to 84.111.255.25484.111.255.255262,142
2984.112.0.0/1484.112.0.1 to 84.115.255.25484.115.255.255262,142
3084.116.0.0/1484.116.0.1 to 84.119.255.25484.119.255.255262,142
3184.120.0.0/1484.120.0.1 to 84.123.255.25484.123.255.255262,142
3284.124.0.0/1484.124.0.1 to 84.127.255.25484.127.255.255262,142
3384.128.0.0/1484.128.0.1 to 84.131.255.25484.131.255.255262,142
3484.132.0.0/1484.132.0.1 to 84.135.255.25484.135.255.255262,142
3584.136.0.0/1484.136.0.1 to 84.139.255.25484.139.255.255262,142
3684.140.0.0/1484.140.0.1 to 84.143.255.25484.143.255.255262,142
3784.144.0.0/1484.144.0.1 to 84.147.255.25484.147.255.255262,142
3884.148.0.0/1484.148.0.1 to 84.151.255.25484.151.255.255262,142
3984.152.0.0/1484.152.0.1 to 84.155.255.25484.155.255.255262,142
4084.156.0.0/1484.156.0.1 to 84.159.255.25484.159.255.255262,142
4184.160.0.0/1484.160.0.1 to 84.163.255.25484.163.255.255262,142
4284.164.0.0/1484.164.0.1 to 84.167.255.25484.167.255.255262,142
4384.168.0.0/1484.168.0.1 to 84.171.255.25484.171.255.255262,142
4484.172.0.0/1484.172.0.1 to 84.175.255.25484.175.255.255262,142
4584.176.0.0/1484.176.0.1 to 84.179.255.25484.179.255.255262,142
4684.180.0.0/1484.180.0.1 to 84.183.255.25484.183.255.255262,142
4784.184.0.0/1484.184.0.1 to 84.187.255.25484.187.255.255262,142
4884.188.0.0/1484.188.0.1 to 84.191.255.25484.191.255.255262,142
4984.192.0.0/1484.192.0.1 to 84.195.255.25484.195.255.255262,142
5084.196.0.0/1484.196.0.1 to 84.199.255.25484.199.255.255262,142
5184.200.0.0/1484.200.0.1 to 84.203.255.25484.203.255.255262,142
5284.204.0.0/1484.204.0.1 to 84.207.255.25484.207.255.255262,142
5384.208.0.0/1484.208.0.1 to 84.211.255.25484.211.255.255262,142
5484.212.0.0/1484.212.0.1 to 84.215.255.25484.215.255.255262,142
5584.216.0.0/1484.216.0.1 to 84.219.255.25484.219.255.255262,142
5684.220.0.0/1484.220.0.1 to 84.223.255.25484.223.255.255262,142
5784.224.0.0/1484.224.0.1 to 84.227.255.25484.227.255.255262,142
5884.228.0.0/1484.228.0.1 to 84.231.255.25484.231.255.255262,142
5984.232.0.0/1484.232.0.1 to 84.235.255.25484.235.255.255262,142
6084.236.0.0/1484.236.0.1 to 84.239.255.25484.239.255.255262,142
6184.240.0.0/1484.240.0.1 to 84.243.255.25484.243.255.255262,142
6284.244.0.0/1484.244.0.1 to 84.247.255.25484.247.255.255262,142
6384.248.0.0/1484.248.0.1 to 84.251.255.25484.251.255.255262,142
6484.252.0.0/1484.252.0.1 to 84.255.255.25484.255.255.255262,142
6585.0.0.0/1485.0.0.1 to 85.3.255.25485.3.255.255262,142
6685.4.0.0/1485.4.0.1 to 85.7.255.25485.7.255.255262,142
6785.8.0.0/1485.8.0.1 to 85.11.255.25485.11.255.255262,142
6885.12.0.0/1485.12.0.1 to 85.15.255.25485.15.255.255262,142
6985.16.0.0/1485.16.0.1 to 85.19.255.25485.19.255.255262,142
7085.20.0.0/1485.20.0.1 to 85.23.255.25485.23.255.255262,142
7185.24.0.0/1485.24.0.1 to 85.27.255.25485.27.255.255262,142
7285.28.0.0/1485.28.0.1 to 85.31.255.25485.31.255.255262,142
7385.32.0.0/1485.32.0.1 to 85.35.255.25485.35.255.255262,142
7485.36.0.0/1485.36.0.1 to 85.39.255.25485.39.255.255262,142
7585.40.0.0/1485.40.0.1 to 85.43.255.25485.43.255.255262,142
7685.44.0.0/1485.44.0.1 to 85.47.255.25485.47.255.255262,142
7785.48.0.0/1485.48.0.1 to 85.51.255.25485.51.255.255262,142
7885.52.0.0/1485.52.0.1 to 85.55.255.25485.55.255.255262,142
7985.56.0.0/1485.56.0.1 to 85.59.255.25485.59.255.255262,142
8085.60.0.0/1485.60.0.1 to 85.63.255.25485.63.255.255262,142
8185.64.0.0/1485.64.0.1 to 85.67.255.25485.67.255.255262,142
8285.68.0.0/1485.68.0.1 to 85.71.255.25485.71.255.255262,142
8385.72.0.0/1485.72.0.1 to 85.75.255.25485.75.255.255262,142
8485.76.0.0/1485.76.0.1 to 85.79.255.25485.79.255.255262,142
8585.80.0.0/1485.80.0.1 to 85.83.255.25485.83.255.255262,142
8685.84.0.0/1485.84.0.1 to 85.87.255.25485.87.255.255262,142
8785.88.0.0/1485.88.0.1 to 85.91.255.25485.91.255.255262,142
8885.92.0.0/1485.92.0.1 to 85.95.255.25485.95.255.255262,142
8985.96.0.0/1485.96.0.1 to 85.99.255.25485.99.255.255262,142
9085.100.0.0/1485.100.0.1 to 85.103.255.25485.103.255.255262,142
9185.104.0.0/1485.104.0.1 to 85.107.255.25485.107.255.255262,142
9285.108.0.0/1485.108.0.1 to 85.111.255.25485.111.255.255262,142
9385.112.0.0/1485.112.0.1 to 85.115.255.25485.115.255.255262,142
9485.116.0.0/1485.116.0.1 to 85.119.255.25485.119.255.255262,142
9585.120.0.0/1485.120.0.1 to 85.123.255.25485.123.255.255262,142
9685.124.0.0/1485.124.0.1 to 85.127.255.25485.127.255.255262,142
9785.128.0.0/1485.128.0.1 to 85.131.255.25485.131.255.255262,142
9885.132.0.0/1485.132.0.1 to 85.135.255.25485.135.255.255262,142
9985.136.0.0/1485.136.0.1 to 85.139.255.25485.139.255.255262,142
10085.140.0.0/1485.140.0.1 to 85.143.255.25485.143.255.255262,142
10185.144.0.0/1485.144.0.1 to 85.147.255.25485.147.255.255262,142
10285.148.0.0/1485.148.0.1 to 85.151.255.25485.151.255.255262,142
10385.152.0.0/1485.152.0.1 to 85.155.255.25485.155.255.255262,142
10485.156.0.0/1485.156.0.1 to 85.159.255.25485.159.255.255262,142
10585.160.0.0/1485.160.0.1 to 85.163.255.25485.163.255.255262,142
10685.164.0.0/1485.164.0.1 to 85.167.255.25485.167.255.255262,142
10785.168.0.0/1485.168.0.1 to 85.171.255.25485.171.255.255262,142
10885.172.0.0/1485.172.0.1 to 85.175.255.25485.175.255.255262,142
10985.176.0.0/1485.176.0.1 to 85.179.255.25485.179.255.255262,142
11085.180.0.0/1485.180.0.1 to 85.183.255.25485.183.255.255262,142
11185.184.0.0/1485.184.0.1 to 85.187.255.25485.187.255.255262,142
11285.188.0.0/1485.188.0.1 to 85.191.255.25485.191.255.255262,142
11385.192.0.0/1485.192.0.1 to 85.195.255.25485.195.255.255262,142
11485.196.0.0/1485.196.0.1 to 85.199.255.25485.199.255.255262,142
11585.200.0.0/1485.200.0.1 to 85.203.255.25485.203.255.255262,142
11685.204.0.0/1485.204.0.1 to 85.207.255.25485.207.255.255262,142
11785.208.0.0/1485.208.0.1 to 85.211.255.25485.211.255.255262,142
11885.212.0.0/1485.212.0.1 to 85.215.255.25485.215.255.255262,142
11985.216.0.0/1485.216.0.1 to 85.219.255.25485.219.255.255262,142
12085.220.0.0/1485.220.0.1 to 85.223.255.25485.223.255.255262,142
12185.224.0.0/1485.224.0.1 to 85.227.255.25485.227.255.255262,142
12285.228.0.0/1485.228.0.1 to 85.231.255.25485.231.255.255262,142
12385.232.0.0/1485.232.0.1 to 85.235.255.25485.235.255.255262,142
12485.236.0.0/1485.236.0.1 to 85.239.255.25485.239.255.255262,142
12585.240.0.0/1485.240.0.1 to 85.243.255.25485.243.255.255262,142
12685.244.0.0/1485.244.0.1 to 85.247.255.25485.247.255.255262,142
12785.248.0.0/1485.248.0.1 to 85.251.255.25485.251.255.255262,142
12885.252.0.0/1485.252.0.1 to 85.255.255.25485.255.255.255262,142
12986.0.0.0/1486.0.0.1 to 86.3.255.25486.3.255.255262,142
13086.4.0.0/1486.4.0.1 to 86.7.255.25486.7.255.255262,142
13186.8.0.0/1486.8.0.1 to 86.11.255.25486.11.255.255262,142
13286.12.0.0/1486.12.0.1 to 86.15.255.25486.15.255.255262,142
13386.16.0.0/1486.16.0.1 to 86.19.255.25486.19.255.255262,142
13486.20.0.0/1486.20.0.1 to 86.23.255.25486.23.255.255262,142
13586.24.0.0/1486.24.0.1 to 86.27.255.25486.27.255.255262,142
13686.28.0.0/1486.28.0.1 to 86.31.255.25486.31.255.255262,142
13786.32.0.0/1486.32.0.1 to 86.35.255.25486.35.255.255262,142
13886.36.0.0/1486.36.0.1 to 86.39.255.25486.39.255.255262,142
13986.40.0.0/1486.40.0.1 to 86.43.255.25486.43.255.255262,142
14086.44.0.0/1486.44.0.1 to 86.47.255.25486.47.255.255262,142
14186.48.0.0/1486.48.0.1 to 86.51.255.25486.51.255.255262,142
14286.52.0.0/1486.52.0.1 to 86.55.255.25486.55.255.255262,142
14386.56.0.0/1486.56.0.1 to 86.59.255.25486.59.255.255262,142
14486.60.0.0/1486.60.0.1 to 86.63.255.25486.63.255.255262,142
14586.64.0.0/1486.64.0.1 to 86.67.255.25486.67.255.255262,142
14686.68.0.0/1486.68.0.1 to 86.71.255.25486.71.255.255262,142
14786.72.0.0/1486.72.0.1 to 86.75.255.25486.75.255.255262,142
14886.76.0.0/1486.76.0.1 to 86.79.255.25486.79.255.255262,142
14986.80.0.0/1486.80.0.1 to 86.83.255.25486.83.255.255262,142
15086.84.0.0/1486.84.0.1 to 86.87.255.25486.87.255.255262,142
15186.88.0.0/1486.88.0.1 to 86.91.255.25486.91.255.255262,142
15286.92.0.0/1486.92.0.1 to 86.95.255.25486.95.255.255262,142
15386.96.0.0/1486.96.0.1 to 86.99.255.25486.99.255.255262,142
15486.100.0.0/1486.100.0.1 to 86.103.255.25486.103.255.255262,142
15586.104.0.0/1486.104.0.1 to 86.107.255.25486.107.255.255262,142
15686.108.0.0/1486.108.0.1 to 86.111.255.25486.111.255.255262,142
15786.112.0.0/1486.112.0.1 to 86.115.255.25486.115.255.255262,142
15886.116.0.0/1486.116.0.1 to 86.119.255.25486.119.255.255262,142
15986.120.0.0/1486.120.0.1 to 86.123.255.25486.123.255.255262,142
16086.124.0.0/1486.124.0.1 to 86.127.255.25486.127.255.255262,142
16186.128.0.0/1486.128.0.1 to 86.131.255.25486.131.255.255262,142
16286.132.0.0/1486.132.0.1 to 86.135.255.25486.135.255.255262,142
16386.136.0.0/1486.136.0.1 to 86.139.255.25486.139.255.255262,142
16486.140.0.0/1486.140.0.1 to 86.143.255.25486.143.255.255262,142
16586.144.0.0/1486.144.0.1 to 86.147.255.25486.147.255.255262,142
16686.148.0.0/1486.148.0.1 to 86.151.255.25486.151.255.255262,142
16786.152.0.0/1486.152.0.1 to 86.155.255.25486.155.255.255262,142
16886.156.0.0/1486.156.0.1 to 86.159.255.25486.159.255.255262,142
16986.160.0.0/1486.160.0.1 to 86.163.255.25486.163.255.255262,142
17086.164.0.0/1486.164.0.1 to 86.167.255.25486.167.255.255262,142
17186.168.0.0/1486.168.0.1 to 86.171.255.25486.171.255.255262,142
17286.172.0.0/1486.172.0.1 to 86.175.255.25486.175.255.255262,142
17386.176.0.0/1486.176.0.1 to 86.179.255.25486.179.255.255262,142
17486.180.0.0/1486.180.0.1 to 86.183.255.25486.183.255.255262,142
17586.184.0.0/1486.184.0.1 to 86.187.255.25486.187.255.255262,142
17686.188.0.0/1486.188.0.1 to 86.191.255.25486.191.255.255262,142
17786.192.0.0/1486.192.0.1 to 86.195.255.25486.195.255.255262,142
17886.196.0.0/1486.196.0.1 to 86.199.255.25486.199.255.255262,142
17986.200.0.0/1486.200.0.1 to 86.203.255.25486.203.255.255262,142
18086.204.0.0/1486.204.0.1 to 86.207.255.25486.207.255.255262,142
18186.208.0.0/1486.208.0.1 to 86.211.255.25486.211.255.255262,142
18286.212.0.0/1486.212.0.1 to 86.215.255.25486.215.255.255262,142
18386.216.0.0/1486.216.0.1 to 86.219.255.25486.219.255.255262,142
18486.220.0.0/1486.220.0.1 to 86.223.255.25486.223.255.255262,142
18586.224.0.0/1486.224.0.1 to 86.227.255.25486.227.255.255262,142
18686.228.0.0/1486.228.0.1 to 86.231.255.25486.231.255.255262,142
18786.232.0.0/1486.232.0.1 to 86.235.255.25486.235.255.255262,142
18886.236.0.0/1486.236.0.1 to 86.239.255.25486.239.255.255262,142
18986.240.0.0/1486.240.0.1 to 86.243.255.25486.243.255.255262,142
19086.244.0.0/1486.244.0.1 to 86.247.255.25486.247.255.255262,142
19186.248.0.0/1486.248.0.1 to 86.251.255.25486.251.255.255262,142
19286.252.0.0/1486.252.0.1 to 86.255.255.25486.255.255.255262,142
19387.0.0.0/1487.0.0.1 to 87.3.255.25487.3.255.255262,142
19487.4.0.0/1487.4.0.1 to 87.7.255.25487.7.255.255262,142
19587.8.0.0/1487.8.0.1 to 87.11.255.25487.11.255.255262,142
19687.12.0.0/1487.12.0.1 to 87.15.255.25487.15.255.255262,142
19787.16.0.0/1487.16.0.1 to 87.19.255.25487.19.255.255262,142
19887.20.0.0/1487.20.0.1 to 87.23.255.25487.23.255.255262,142
19987.24.0.0/1487.24.0.1 to 87.27.255.25487.27.255.255262,142
20087.28.0.0/1487.28.0.1 to 87.31.255.25487.31.255.255262,142
20187.32.0.0/1487.32.0.1 to 87.35.255.25487.35.255.255262,142
20287.36.0.0/1487.36.0.1 to 87.39.255.25487.39.255.255262,142
20387.40.0.0/1487.40.0.1 to 87.43.255.25487.43.255.255262,142
20487.44.0.0/1487.44.0.1 to 87.47.255.25487.47.255.255262,142
20587.48.0.0/1487.48.0.1 to 87.51.255.25487.51.255.255262,142
20687.52.0.0/1487.52.0.1 to 87.55.255.25487.55.255.255262,142
20787.56.0.0/1487.56.0.1 to 87.59.255.25487.59.255.255262,142
20887.60.0.0/1487.60.0.1 to 87.63.255.25487.63.255.255262,142
20987.64.0.0/1487.64.0.1 to 87.67.255.25487.67.255.255262,142
21087.68.0.0/1487.68.0.1 to 87.71.255.25487.71.255.255262,142
21187.72.0.0/1487.72.0.1 to 87.75.255.25487.75.255.255262,142
21287.76.0.0/1487.76.0.1 to 87.79.255.25487.79.255.255262,142
21387.80.0.0/1487.80.0.1 to 87.83.255.25487.83.255.255262,142
21487.84.0.0/1487.84.0.1 to 87.87.255.25487.87.255.255262,142
21587.88.0.0/1487.88.0.1 to 87.91.255.25487.91.255.255262,142
21687.92.0.0/1487.92.0.1 to 87.95.255.25487.95.255.255262,142
21787.96.0.0/1487.96.0.1 to 87.99.255.25487.99.255.255262,142
21887.100.0.0/1487.100.0.1 to 87.103.255.25487.103.255.255262,142
21987.104.0.0/1487.104.0.1 to 87.107.255.25487.107.255.255262,142
22087.108.0.0/1487.108.0.1 to 87.111.255.25487.111.255.255262,142
22187.112.0.0/1487.112.0.1 to 87.115.255.25487.115.255.255262,142
22287.116.0.0/1487.116.0.1 to 87.119.255.25487.119.255.255262,142
22387.120.0.0/1487.120.0.1 to 87.123.255.25487.123.255.255262,142
22487.124.0.0/1487.124.0.1 to 87.127.255.25487.127.255.255262,142
22587.128.0.0/1487.128.0.1 to 87.131.255.25487.131.255.255262,142
22687.132.0.0/1487.132.0.1 to 87.135.255.25487.135.255.255262,142
22787.136.0.0/1487.136.0.1 to 87.139.255.25487.139.255.255262,142
22887.140.0.0/1487.140.0.1 to 87.143.255.25487.143.255.255262,142
22987.144.0.0/1487.144.0.1 to 87.147.255.25487.147.255.255262,142
23087.148.0.0/1487.148.0.1 to 87.151.255.25487.151.255.255262,142
23187.152.0.0/1487.152.0.1 to 87.155.255.25487.155.255.255262,142
23287.156.0.0/1487.156.0.1 to 87.159.255.25487.159.255.255262,142
23387.160.0.0/1487.160.0.1 to 87.163.255.25487.163.255.255262,142
23487.164.0.0/1487.164.0.1 to 87.167.255.25487.167.255.255262,142
23587.168.0.0/1487.168.0.1 to 87.171.255.25487.171.255.255262,142
23687.172.0.0/1487.172.0.1 to 87.175.255.25487.175.255.255262,142
23787.176.0.0/1487.176.0.1 to 87.179.255.25487.179.255.255262,142
23887.180.0.0/1487.180.0.1 to 87.183.255.25487.183.255.255262,142
23987.184.0.0/1487.184.0.1 to 87.187.255.25487.187.255.255262,142
24087.188.0.0/1487.188.0.1 to 87.191.255.25487.191.255.255262,142
24187.192.0.0/1487.192.0.1 to 87.195.255.25487.195.255.255262,142
24287.196.0.0/1487.196.0.1 to 87.199.255.25487.199.255.255262,142
24387.200.0.0/1487.200.0.1 to 87.203.255.25487.203.255.255262,142
24487.204.0.0/1487.204.0.1 to 87.207.255.25487.207.255.255262,142
24587.208.0.0/1487.208.0.1 to 87.211.255.25487.211.255.255262,142
24687.212.0.0/1487.212.0.1 to 87.215.255.25487.215.255.255262,142
24787.216.0.0/1487.216.0.1 to 87.219.255.25487.219.255.255262,142
24887.220.0.0/1487.220.0.1 to 87.223.255.25487.223.255.255262,142
24987.224.0.0/1487.224.0.1 to 87.227.255.25487.227.255.255262,142
25087.228.0.0/1487.228.0.1 to 87.231.255.25487.231.255.255262,142
25187.232.0.0/1487.232.0.1 to 87.235.255.25487.235.255.255262,142
25287.236.0.0/1487.236.0.1 to 87.239.255.25487.239.255.255262,142
25387.240.0.0/1487.240.0.1 to 87.243.255.25487.243.255.255262,142
25487.244.0.0/1487.244.0.1 to 87.247.255.25487.247.255.255262,142
25587.248.0.0/1487.248.0.1 to 87.251.255.25487.251.255.255262,142
25687.252.0.0/1487.252.0.1 to 87.255.255.25487.255.255.255262,142

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.