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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.

Network88.0.0.0/6
Usable hosts67,108,862
Subnet mask252.0.0.0
Addresses67,108,864
Network address
88.0.0.0
Broadcast address
91.255.255.255
First usable
88.0.0.1
Last usable
91.255.255.254
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 58000000 · Integer 1476395008 to 1543503871
Reverse DNS zones
88.in-addr.arpa
89.in-addr.arpa
90.in-addr.arpa
91.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
Address01011000.00000000.00000000.0000000088.0.0.0
Subnet mask11111100.00000000.00000000.00000000252.0.0.0
Network01011000.00000000.00000000.0000000088.0.0.0
Broadcast01011011.11111111.11111111.1111111191.255.255.255
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)

88.0.0.0/6 makes 256 subnets of /14.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
188.0.0.0/1488.0.0.1 to 88.3.255.25488.3.255.255262,142
288.4.0.0/1488.4.0.1 to 88.7.255.25488.7.255.255262,142
388.8.0.0/1488.8.0.1 to 88.11.255.25488.11.255.255262,142
488.12.0.0/1488.12.0.1 to 88.15.255.25488.15.255.255262,142
588.16.0.0/1488.16.0.1 to 88.19.255.25488.19.255.255262,142
688.20.0.0/1488.20.0.1 to 88.23.255.25488.23.255.255262,142
788.24.0.0/1488.24.0.1 to 88.27.255.25488.27.255.255262,142
888.28.0.0/1488.28.0.1 to 88.31.255.25488.31.255.255262,142
988.32.0.0/1488.32.0.1 to 88.35.255.25488.35.255.255262,142
1088.36.0.0/1488.36.0.1 to 88.39.255.25488.39.255.255262,142
1188.40.0.0/1488.40.0.1 to 88.43.255.25488.43.255.255262,142
1288.44.0.0/1488.44.0.1 to 88.47.255.25488.47.255.255262,142
1388.48.0.0/1488.48.0.1 to 88.51.255.25488.51.255.255262,142
1488.52.0.0/1488.52.0.1 to 88.55.255.25488.55.255.255262,142
1588.56.0.0/1488.56.0.1 to 88.59.255.25488.59.255.255262,142
1688.60.0.0/1488.60.0.1 to 88.63.255.25488.63.255.255262,142
1788.64.0.0/1488.64.0.1 to 88.67.255.25488.67.255.255262,142
1888.68.0.0/1488.68.0.1 to 88.71.255.25488.71.255.255262,142
1988.72.0.0/1488.72.0.1 to 88.75.255.25488.75.255.255262,142
2088.76.0.0/1488.76.0.1 to 88.79.255.25488.79.255.255262,142
2188.80.0.0/1488.80.0.1 to 88.83.255.25488.83.255.255262,142
2288.84.0.0/1488.84.0.1 to 88.87.255.25488.87.255.255262,142
2388.88.0.0/1488.88.0.1 to 88.91.255.25488.91.255.255262,142
2488.92.0.0/1488.92.0.1 to 88.95.255.25488.95.255.255262,142
2588.96.0.0/1488.96.0.1 to 88.99.255.25488.99.255.255262,142
2688.100.0.0/1488.100.0.1 to 88.103.255.25488.103.255.255262,142
2788.104.0.0/1488.104.0.1 to 88.107.255.25488.107.255.255262,142
2888.108.0.0/1488.108.0.1 to 88.111.255.25488.111.255.255262,142
2988.112.0.0/1488.112.0.1 to 88.115.255.25488.115.255.255262,142
3088.116.0.0/1488.116.0.1 to 88.119.255.25488.119.255.255262,142
3188.120.0.0/1488.120.0.1 to 88.123.255.25488.123.255.255262,142
3288.124.0.0/1488.124.0.1 to 88.127.255.25488.127.255.255262,142
3388.128.0.0/1488.128.0.1 to 88.131.255.25488.131.255.255262,142
3488.132.0.0/1488.132.0.1 to 88.135.255.25488.135.255.255262,142
3588.136.0.0/1488.136.0.1 to 88.139.255.25488.139.255.255262,142
3688.140.0.0/1488.140.0.1 to 88.143.255.25488.143.255.255262,142
3788.144.0.0/1488.144.0.1 to 88.147.255.25488.147.255.255262,142
3888.148.0.0/1488.148.0.1 to 88.151.255.25488.151.255.255262,142
3988.152.0.0/1488.152.0.1 to 88.155.255.25488.155.255.255262,142
4088.156.0.0/1488.156.0.1 to 88.159.255.25488.159.255.255262,142
4188.160.0.0/1488.160.0.1 to 88.163.255.25488.163.255.255262,142
4288.164.0.0/1488.164.0.1 to 88.167.255.25488.167.255.255262,142
4388.168.0.0/1488.168.0.1 to 88.171.255.25488.171.255.255262,142
4488.172.0.0/1488.172.0.1 to 88.175.255.25488.175.255.255262,142
4588.176.0.0/1488.176.0.1 to 88.179.255.25488.179.255.255262,142
4688.180.0.0/1488.180.0.1 to 88.183.255.25488.183.255.255262,142
4788.184.0.0/1488.184.0.1 to 88.187.255.25488.187.255.255262,142
4888.188.0.0/1488.188.0.1 to 88.191.255.25488.191.255.255262,142
4988.192.0.0/1488.192.0.1 to 88.195.255.25488.195.255.255262,142
5088.196.0.0/1488.196.0.1 to 88.199.255.25488.199.255.255262,142
5188.200.0.0/1488.200.0.1 to 88.203.255.25488.203.255.255262,142
5288.204.0.0/1488.204.0.1 to 88.207.255.25488.207.255.255262,142
5388.208.0.0/1488.208.0.1 to 88.211.255.25488.211.255.255262,142
5488.212.0.0/1488.212.0.1 to 88.215.255.25488.215.255.255262,142
5588.216.0.0/1488.216.0.1 to 88.219.255.25488.219.255.255262,142
5688.220.0.0/1488.220.0.1 to 88.223.255.25488.223.255.255262,142
5788.224.0.0/1488.224.0.1 to 88.227.255.25488.227.255.255262,142
5888.228.0.0/1488.228.0.1 to 88.231.255.25488.231.255.255262,142
5988.232.0.0/1488.232.0.1 to 88.235.255.25488.235.255.255262,142
6088.236.0.0/1488.236.0.1 to 88.239.255.25488.239.255.255262,142
6188.240.0.0/1488.240.0.1 to 88.243.255.25488.243.255.255262,142
6288.244.0.0/1488.244.0.1 to 88.247.255.25488.247.255.255262,142
6388.248.0.0/1488.248.0.1 to 88.251.255.25488.251.255.255262,142
6488.252.0.0/1488.252.0.1 to 88.255.255.25488.255.255.255262,142
6589.0.0.0/1489.0.0.1 to 89.3.255.25489.3.255.255262,142
6689.4.0.0/1489.4.0.1 to 89.7.255.25489.7.255.255262,142
6789.8.0.0/1489.8.0.1 to 89.11.255.25489.11.255.255262,142
6889.12.0.0/1489.12.0.1 to 89.15.255.25489.15.255.255262,142
6989.16.0.0/1489.16.0.1 to 89.19.255.25489.19.255.255262,142
7089.20.0.0/1489.20.0.1 to 89.23.255.25489.23.255.255262,142
7189.24.0.0/1489.24.0.1 to 89.27.255.25489.27.255.255262,142
7289.28.0.0/1489.28.0.1 to 89.31.255.25489.31.255.255262,142
7389.32.0.0/1489.32.0.1 to 89.35.255.25489.35.255.255262,142
7489.36.0.0/1489.36.0.1 to 89.39.255.25489.39.255.255262,142
7589.40.0.0/1489.40.0.1 to 89.43.255.25489.43.255.255262,142
7689.44.0.0/1489.44.0.1 to 89.47.255.25489.47.255.255262,142
7789.48.0.0/1489.48.0.1 to 89.51.255.25489.51.255.255262,142
7889.52.0.0/1489.52.0.1 to 89.55.255.25489.55.255.255262,142
7989.56.0.0/1489.56.0.1 to 89.59.255.25489.59.255.255262,142
8089.60.0.0/1489.60.0.1 to 89.63.255.25489.63.255.255262,142
8189.64.0.0/1489.64.0.1 to 89.67.255.25489.67.255.255262,142
8289.68.0.0/1489.68.0.1 to 89.71.255.25489.71.255.255262,142
8389.72.0.0/1489.72.0.1 to 89.75.255.25489.75.255.255262,142
8489.76.0.0/1489.76.0.1 to 89.79.255.25489.79.255.255262,142
8589.80.0.0/1489.80.0.1 to 89.83.255.25489.83.255.255262,142
8689.84.0.0/1489.84.0.1 to 89.87.255.25489.87.255.255262,142
8789.88.0.0/1489.88.0.1 to 89.91.255.25489.91.255.255262,142
8889.92.0.0/1489.92.0.1 to 89.95.255.25489.95.255.255262,142
8989.96.0.0/1489.96.0.1 to 89.99.255.25489.99.255.255262,142
9089.100.0.0/1489.100.0.1 to 89.103.255.25489.103.255.255262,142
9189.104.0.0/1489.104.0.1 to 89.107.255.25489.107.255.255262,142
9289.108.0.0/1489.108.0.1 to 89.111.255.25489.111.255.255262,142
9389.112.0.0/1489.112.0.1 to 89.115.255.25489.115.255.255262,142
9489.116.0.0/1489.116.0.1 to 89.119.255.25489.119.255.255262,142
9589.120.0.0/1489.120.0.1 to 89.123.255.25489.123.255.255262,142
9689.124.0.0/1489.124.0.1 to 89.127.255.25489.127.255.255262,142
9789.128.0.0/1489.128.0.1 to 89.131.255.25489.131.255.255262,142
9889.132.0.0/1489.132.0.1 to 89.135.255.25489.135.255.255262,142
9989.136.0.0/1489.136.0.1 to 89.139.255.25489.139.255.255262,142
10089.140.0.0/1489.140.0.1 to 89.143.255.25489.143.255.255262,142
10189.144.0.0/1489.144.0.1 to 89.147.255.25489.147.255.255262,142
10289.148.0.0/1489.148.0.1 to 89.151.255.25489.151.255.255262,142
10389.152.0.0/1489.152.0.1 to 89.155.255.25489.155.255.255262,142
10489.156.0.0/1489.156.0.1 to 89.159.255.25489.159.255.255262,142
10589.160.0.0/1489.160.0.1 to 89.163.255.25489.163.255.255262,142
10689.164.0.0/1489.164.0.1 to 89.167.255.25489.167.255.255262,142
10789.168.0.0/1489.168.0.1 to 89.171.255.25489.171.255.255262,142
10889.172.0.0/1489.172.0.1 to 89.175.255.25489.175.255.255262,142
10989.176.0.0/1489.176.0.1 to 89.179.255.25489.179.255.255262,142
11089.180.0.0/1489.180.0.1 to 89.183.255.25489.183.255.255262,142
11189.184.0.0/1489.184.0.1 to 89.187.255.25489.187.255.255262,142
11289.188.0.0/1489.188.0.1 to 89.191.255.25489.191.255.255262,142
11389.192.0.0/1489.192.0.1 to 89.195.255.25489.195.255.255262,142
11489.196.0.0/1489.196.0.1 to 89.199.255.25489.199.255.255262,142
11589.200.0.0/1489.200.0.1 to 89.203.255.25489.203.255.255262,142
11689.204.0.0/1489.204.0.1 to 89.207.255.25489.207.255.255262,142
11789.208.0.0/1489.208.0.1 to 89.211.255.25489.211.255.255262,142
11889.212.0.0/1489.212.0.1 to 89.215.255.25489.215.255.255262,142
11989.216.0.0/1489.216.0.1 to 89.219.255.25489.219.255.255262,142
12089.220.0.0/1489.220.0.1 to 89.223.255.25489.223.255.255262,142
12189.224.0.0/1489.224.0.1 to 89.227.255.25489.227.255.255262,142
12289.228.0.0/1489.228.0.1 to 89.231.255.25489.231.255.255262,142
12389.232.0.0/1489.232.0.1 to 89.235.255.25489.235.255.255262,142
12489.236.0.0/1489.236.0.1 to 89.239.255.25489.239.255.255262,142
12589.240.0.0/1489.240.0.1 to 89.243.255.25489.243.255.255262,142
12689.244.0.0/1489.244.0.1 to 89.247.255.25489.247.255.255262,142
12789.248.0.0/1489.248.0.1 to 89.251.255.25489.251.255.255262,142
12889.252.0.0/1489.252.0.1 to 89.255.255.25489.255.255.255262,142
12990.0.0.0/1490.0.0.1 to 90.3.255.25490.3.255.255262,142
13090.4.0.0/1490.4.0.1 to 90.7.255.25490.7.255.255262,142
13190.8.0.0/1490.8.0.1 to 90.11.255.25490.11.255.255262,142
13290.12.0.0/1490.12.0.1 to 90.15.255.25490.15.255.255262,142
13390.16.0.0/1490.16.0.1 to 90.19.255.25490.19.255.255262,142
13490.20.0.0/1490.20.0.1 to 90.23.255.25490.23.255.255262,142
13590.24.0.0/1490.24.0.1 to 90.27.255.25490.27.255.255262,142
13690.28.0.0/1490.28.0.1 to 90.31.255.25490.31.255.255262,142
13790.32.0.0/1490.32.0.1 to 90.35.255.25490.35.255.255262,142
13890.36.0.0/1490.36.0.1 to 90.39.255.25490.39.255.255262,142
13990.40.0.0/1490.40.0.1 to 90.43.255.25490.43.255.255262,142
14090.44.0.0/1490.44.0.1 to 90.47.255.25490.47.255.255262,142
14190.48.0.0/1490.48.0.1 to 90.51.255.25490.51.255.255262,142
14290.52.0.0/1490.52.0.1 to 90.55.255.25490.55.255.255262,142
14390.56.0.0/1490.56.0.1 to 90.59.255.25490.59.255.255262,142
14490.60.0.0/1490.60.0.1 to 90.63.255.25490.63.255.255262,142
14590.64.0.0/1490.64.0.1 to 90.67.255.25490.67.255.255262,142
14690.68.0.0/1490.68.0.1 to 90.71.255.25490.71.255.255262,142
14790.72.0.0/1490.72.0.1 to 90.75.255.25490.75.255.255262,142
14890.76.0.0/1490.76.0.1 to 90.79.255.25490.79.255.255262,142
14990.80.0.0/1490.80.0.1 to 90.83.255.25490.83.255.255262,142
15090.84.0.0/1490.84.0.1 to 90.87.255.25490.87.255.255262,142
15190.88.0.0/1490.88.0.1 to 90.91.255.25490.91.255.255262,142
15290.92.0.0/1490.92.0.1 to 90.95.255.25490.95.255.255262,142
15390.96.0.0/1490.96.0.1 to 90.99.255.25490.99.255.255262,142
15490.100.0.0/1490.100.0.1 to 90.103.255.25490.103.255.255262,142
15590.104.0.0/1490.104.0.1 to 90.107.255.25490.107.255.255262,142
15690.108.0.0/1490.108.0.1 to 90.111.255.25490.111.255.255262,142
15790.112.0.0/1490.112.0.1 to 90.115.255.25490.115.255.255262,142
15890.116.0.0/1490.116.0.1 to 90.119.255.25490.119.255.255262,142
15990.120.0.0/1490.120.0.1 to 90.123.255.25490.123.255.255262,142
16090.124.0.0/1490.124.0.1 to 90.127.255.25490.127.255.255262,142
16190.128.0.0/1490.128.0.1 to 90.131.255.25490.131.255.255262,142
16290.132.0.0/1490.132.0.1 to 90.135.255.25490.135.255.255262,142
16390.136.0.0/1490.136.0.1 to 90.139.255.25490.139.255.255262,142
16490.140.0.0/1490.140.0.1 to 90.143.255.25490.143.255.255262,142
16590.144.0.0/1490.144.0.1 to 90.147.255.25490.147.255.255262,142
16690.148.0.0/1490.148.0.1 to 90.151.255.25490.151.255.255262,142
16790.152.0.0/1490.152.0.1 to 90.155.255.25490.155.255.255262,142
16890.156.0.0/1490.156.0.1 to 90.159.255.25490.159.255.255262,142
16990.160.0.0/1490.160.0.1 to 90.163.255.25490.163.255.255262,142
17090.164.0.0/1490.164.0.1 to 90.167.255.25490.167.255.255262,142
17190.168.0.0/1490.168.0.1 to 90.171.255.25490.171.255.255262,142
17290.172.0.0/1490.172.0.1 to 90.175.255.25490.175.255.255262,142
17390.176.0.0/1490.176.0.1 to 90.179.255.25490.179.255.255262,142
17490.180.0.0/1490.180.0.1 to 90.183.255.25490.183.255.255262,142
17590.184.0.0/1490.184.0.1 to 90.187.255.25490.187.255.255262,142
17690.188.0.0/1490.188.0.1 to 90.191.255.25490.191.255.255262,142
17790.192.0.0/1490.192.0.1 to 90.195.255.25490.195.255.255262,142
17890.196.0.0/1490.196.0.1 to 90.199.255.25490.199.255.255262,142
17990.200.0.0/1490.200.0.1 to 90.203.255.25490.203.255.255262,142
18090.204.0.0/1490.204.0.1 to 90.207.255.25490.207.255.255262,142
18190.208.0.0/1490.208.0.1 to 90.211.255.25490.211.255.255262,142
18290.212.0.0/1490.212.0.1 to 90.215.255.25490.215.255.255262,142
18390.216.0.0/1490.216.0.1 to 90.219.255.25490.219.255.255262,142
18490.220.0.0/1490.220.0.1 to 90.223.255.25490.223.255.255262,142
18590.224.0.0/1490.224.0.1 to 90.227.255.25490.227.255.255262,142
18690.228.0.0/1490.228.0.1 to 90.231.255.25490.231.255.255262,142
18790.232.0.0/1490.232.0.1 to 90.235.255.25490.235.255.255262,142
18890.236.0.0/1490.236.0.1 to 90.239.255.25490.239.255.255262,142
18990.240.0.0/1490.240.0.1 to 90.243.255.25490.243.255.255262,142
19090.244.0.0/1490.244.0.1 to 90.247.255.25490.247.255.255262,142
19190.248.0.0/1490.248.0.1 to 90.251.255.25490.251.255.255262,142
19290.252.0.0/1490.252.0.1 to 90.255.255.25490.255.255.255262,142
19391.0.0.0/1491.0.0.1 to 91.3.255.25491.3.255.255262,142
19491.4.0.0/1491.4.0.1 to 91.7.255.25491.7.255.255262,142
19591.8.0.0/1491.8.0.1 to 91.11.255.25491.11.255.255262,142
19691.12.0.0/1491.12.0.1 to 91.15.255.25491.15.255.255262,142
19791.16.0.0/1491.16.0.1 to 91.19.255.25491.19.255.255262,142
19891.20.0.0/1491.20.0.1 to 91.23.255.25491.23.255.255262,142
19991.24.0.0/1491.24.0.1 to 91.27.255.25491.27.255.255262,142
20091.28.0.0/1491.28.0.1 to 91.31.255.25491.31.255.255262,142
20191.32.0.0/1491.32.0.1 to 91.35.255.25491.35.255.255262,142
20291.36.0.0/1491.36.0.1 to 91.39.255.25491.39.255.255262,142
20391.40.0.0/1491.40.0.1 to 91.43.255.25491.43.255.255262,142
20491.44.0.0/1491.44.0.1 to 91.47.255.25491.47.255.255262,142
20591.48.0.0/1491.48.0.1 to 91.51.255.25491.51.255.255262,142
20691.52.0.0/1491.52.0.1 to 91.55.255.25491.55.255.255262,142
20791.56.0.0/1491.56.0.1 to 91.59.255.25491.59.255.255262,142
20891.60.0.0/1491.60.0.1 to 91.63.255.25491.63.255.255262,142
20991.64.0.0/1491.64.0.1 to 91.67.255.25491.67.255.255262,142
21091.68.0.0/1491.68.0.1 to 91.71.255.25491.71.255.255262,142
21191.72.0.0/1491.72.0.1 to 91.75.255.25491.75.255.255262,142
21291.76.0.0/1491.76.0.1 to 91.79.255.25491.79.255.255262,142
21391.80.0.0/1491.80.0.1 to 91.83.255.25491.83.255.255262,142
21491.84.0.0/1491.84.0.1 to 91.87.255.25491.87.255.255262,142
21591.88.0.0/1491.88.0.1 to 91.91.255.25491.91.255.255262,142
21691.92.0.0/1491.92.0.1 to 91.95.255.25491.95.255.255262,142
21791.96.0.0/1491.96.0.1 to 91.99.255.25491.99.255.255262,142
21891.100.0.0/1491.100.0.1 to 91.103.255.25491.103.255.255262,142
21991.104.0.0/1491.104.0.1 to 91.107.255.25491.107.255.255262,142
22091.108.0.0/1491.108.0.1 to 91.111.255.25491.111.255.255262,142
22191.112.0.0/1491.112.0.1 to 91.115.255.25491.115.255.255262,142
22291.116.0.0/1491.116.0.1 to 91.119.255.25491.119.255.255262,142
22391.120.0.0/1491.120.0.1 to 91.123.255.25491.123.255.255262,142
22491.124.0.0/1491.124.0.1 to 91.127.255.25491.127.255.255262,142
22591.128.0.0/1491.128.0.1 to 91.131.255.25491.131.255.255262,142
22691.132.0.0/1491.132.0.1 to 91.135.255.25491.135.255.255262,142
22791.136.0.0/1491.136.0.1 to 91.139.255.25491.139.255.255262,142
22891.140.0.0/1491.140.0.1 to 91.143.255.25491.143.255.255262,142
22991.144.0.0/1491.144.0.1 to 91.147.255.25491.147.255.255262,142
23091.148.0.0/1491.148.0.1 to 91.151.255.25491.151.255.255262,142
23191.152.0.0/1491.152.0.1 to 91.155.255.25491.155.255.255262,142
23291.156.0.0/1491.156.0.1 to 91.159.255.25491.159.255.255262,142
23391.160.0.0/1491.160.0.1 to 91.163.255.25491.163.255.255262,142
23491.164.0.0/1491.164.0.1 to 91.167.255.25491.167.255.255262,142
23591.168.0.0/1491.168.0.1 to 91.171.255.25491.171.255.255262,142
23691.172.0.0/1491.172.0.1 to 91.175.255.25491.175.255.255262,142
23791.176.0.0/1491.176.0.1 to 91.179.255.25491.179.255.255262,142
23891.180.0.0/1491.180.0.1 to 91.183.255.25491.183.255.255262,142
23991.184.0.0/1491.184.0.1 to 91.187.255.25491.187.255.255262,142
24091.188.0.0/1491.188.0.1 to 91.191.255.25491.191.255.255262,142
24191.192.0.0/1491.192.0.1 to 91.195.255.25491.195.255.255262,142
24291.196.0.0/1491.196.0.1 to 91.199.255.25491.199.255.255262,142
24391.200.0.0/1491.200.0.1 to 91.203.255.25491.203.255.255262,142
24491.204.0.0/1491.204.0.1 to 91.207.255.25491.207.255.255262,142
24591.208.0.0/1491.208.0.1 to 91.211.255.25491.211.255.255262,142
24691.212.0.0/1491.212.0.1 to 91.215.255.25491.215.255.255262,142
24791.216.0.0/1491.216.0.1 to 91.219.255.25491.219.255.255262,142
24891.220.0.0/1491.220.0.1 to 91.223.255.25491.223.255.255262,142
24991.224.0.0/1491.224.0.1 to 91.227.255.25491.227.255.255262,142
25091.228.0.0/1491.228.0.1 to 91.231.255.25491.231.255.255262,142
25191.232.0.0/1491.232.0.1 to 91.235.255.25491.235.255.255262,142
25291.236.0.0/1491.236.0.1 to 91.239.255.25491.239.255.255262,142
25391.240.0.0/1491.240.0.1 to 91.243.255.25491.243.255.255262,142
25491.244.0.0/1491.244.0.1 to 91.247.255.25491.247.255.255262,142
25591.248.0.0/1491.248.0.1 to 91.251.255.25491.251.255.255262,142
25691.252.0.0/1491.252.0.1 to 91.255.255.25491.255.255.255262,142

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.