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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/15
/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 512 subnets of /15; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
188.0.0.0/1588.0.0.1 to 88.1.255.25488.1.255.255131,070
288.2.0.0/1588.2.0.1 to 88.3.255.25488.3.255.255131,070
388.4.0.0/1588.4.0.1 to 88.5.255.25488.5.255.255131,070
488.6.0.0/1588.6.0.1 to 88.7.255.25488.7.255.255131,070
588.8.0.0/1588.8.0.1 to 88.9.255.25488.9.255.255131,070
688.10.0.0/1588.10.0.1 to 88.11.255.25488.11.255.255131,070
788.12.0.0/1588.12.0.1 to 88.13.255.25488.13.255.255131,070
888.14.0.0/1588.14.0.1 to 88.15.255.25488.15.255.255131,070
988.16.0.0/1588.16.0.1 to 88.17.255.25488.17.255.255131,070
1088.18.0.0/1588.18.0.1 to 88.19.255.25488.19.255.255131,070
1188.20.0.0/1588.20.0.1 to 88.21.255.25488.21.255.255131,070
1288.22.0.0/1588.22.0.1 to 88.23.255.25488.23.255.255131,070
1388.24.0.0/1588.24.0.1 to 88.25.255.25488.25.255.255131,070
1488.26.0.0/1588.26.0.1 to 88.27.255.25488.27.255.255131,070
1588.28.0.0/1588.28.0.1 to 88.29.255.25488.29.255.255131,070
1688.30.0.0/1588.30.0.1 to 88.31.255.25488.31.255.255131,070
1788.32.0.0/1588.32.0.1 to 88.33.255.25488.33.255.255131,070
1888.34.0.0/1588.34.0.1 to 88.35.255.25488.35.255.255131,070
1988.36.0.0/1588.36.0.1 to 88.37.255.25488.37.255.255131,070
2088.38.0.0/1588.38.0.1 to 88.39.255.25488.39.255.255131,070
2188.40.0.0/1588.40.0.1 to 88.41.255.25488.41.255.255131,070
2288.42.0.0/1588.42.0.1 to 88.43.255.25488.43.255.255131,070
2388.44.0.0/1588.44.0.1 to 88.45.255.25488.45.255.255131,070
2488.46.0.0/1588.46.0.1 to 88.47.255.25488.47.255.255131,070
2588.48.0.0/1588.48.0.1 to 88.49.255.25488.49.255.255131,070
2688.50.0.0/1588.50.0.1 to 88.51.255.25488.51.255.255131,070
2788.52.0.0/1588.52.0.1 to 88.53.255.25488.53.255.255131,070
2888.54.0.0/1588.54.0.1 to 88.55.255.25488.55.255.255131,070
2988.56.0.0/1588.56.0.1 to 88.57.255.25488.57.255.255131,070
3088.58.0.0/1588.58.0.1 to 88.59.255.25488.59.255.255131,070
3188.60.0.0/1588.60.0.1 to 88.61.255.25488.61.255.255131,070
3288.62.0.0/1588.62.0.1 to 88.63.255.25488.63.255.255131,070
3388.64.0.0/1588.64.0.1 to 88.65.255.25488.65.255.255131,070
3488.66.0.0/1588.66.0.1 to 88.67.255.25488.67.255.255131,070
3588.68.0.0/1588.68.0.1 to 88.69.255.25488.69.255.255131,070
3688.70.0.0/1588.70.0.1 to 88.71.255.25488.71.255.255131,070
3788.72.0.0/1588.72.0.1 to 88.73.255.25488.73.255.255131,070
3888.74.0.0/1588.74.0.1 to 88.75.255.25488.75.255.255131,070
3988.76.0.0/1588.76.0.1 to 88.77.255.25488.77.255.255131,070
4088.78.0.0/1588.78.0.1 to 88.79.255.25488.79.255.255131,070
4188.80.0.0/1588.80.0.1 to 88.81.255.25488.81.255.255131,070
4288.82.0.0/1588.82.0.1 to 88.83.255.25488.83.255.255131,070
4388.84.0.0/1588.84.0.1 to 88.85.255.25488.85.255.255131,070
4488.86.0.0/1588.86.0.1 to 88.87.255.25488.87.255.255131,070
4588.88.0.0/1588.88.0.1 to 88.89.255.25488.89.255.255131,070
4688.90.0.0/1588.90.0.1 to 88.91.255.25488.91.255.255131,070
4788.92.0.0/1588.92.0.1 to 88.93.255.25488.93.255.255131,070
4888.94.0.0/1588.94.0.1 to 88.95.255.25488.95.255.255131,070
4988.96.0.0/1588.96.0.1 to 88.97.255.25488.97.255.255131,070
5088.98.0.0/1588.98.0.1 to 88.99.255.25488.99.255.255131,070
5188.100.0.0/1588.100.0.1 to 88.101.255.25488.101.255.255131,070
5288.102.0.0/1588.102.0.1 to 88.103.255.25488.103.255.255131,070
5388.104.0.0/1588.104.0.1 to 88.105.255.25488.105.255.255131,070
5488.106.0.0/1588.106.0.1 to 88.107.255.25488.107.255.255131,070
5588.108.0.0/1588.108.0.1 to 88.109.255.25488.109.255.255131,070
5688.110.0.0/1588.110.0.1 to 88.111.255.25488.111.255.255131,070
5788.112.0.0/1588.112.0.1 to 88.113.255.25488.113.255.255131,070
5888.114.0.0/1588.114.0.1 to 88.115.255.25488.115.255.255131,070
5988.116.0.0/1588.116.0.1 to 88.117.255.25488.117.255.255131,070
6088.118.0.0/1588.118.0.1 to 88.119.255.25488.119.255.255131,070
6188.120.0.0/1588.120.0.1 to 88.121.255.25488.121.255.255131,070
6288.122.0.0/1588.122.0.1 to 88.123.255.25488.123.255.255131,070
6388.124.0.0/1588.124.0.1 to 88.125.255.25488.125.255.255131,070
6488.126.0.0/1588.126.0.1 to 88.127.255.25488.127.255.255131,070
6588.128.0.0/1588.128.0.1 to 88.129.255.25488.129.255.255131,070
6688.130.0.0/1588.130.0.1 to 88.131.255.25488.131.255.255131,070
6788.132.0.0/1588.132.0.1 to 88.133.255.25488.133.255.255131,070
6888.134.0.0/1588.134.0.1 to 88.135.255.25488.135.255.255131,070
6988.136.0.0/1588.136.0.1 to 88.137.255.25488.137.255.255131,070
7088.138.0.0/1588.138.0.1 to 88.139.255.25488.139.255.255131,070
7188.140.0.0/1588.140.0.1 to 88.141.255.25488.141.255.255131,070
7288.142.0.0/1588.142.0.1 to 88.143.255.25488.143.255.255131,070
7388.144.0.0/1588.144.0.1 to 88.145.255.25488.145.255.255131,070
7488.146.0.0/1588.146.0.1 to 88.147.255.25488.147.255.255131,070
7588.148.0.0/1588.148.0.1 to 88.149.255.25488.149.255.255131,070
7688.150.0.0/1588.150.0.1 to 88.151.255.25488.151.255.255131,070
7788.152.0.0/1588.152.0.1 to 88.153.255.25488.153.255.255131,070
7888.154.0.0/1588.154.0.1 to 88.155.255.25488.155.255.255131,070
7988.156.0.0/1588.156.0.1 to 88.157.255.25488.157.255.255131,070
8088.158.0.0/1588.158.0.1 to 88.159.255.25488.159.255.255131,070
8188.160.0.0/1588.160.0.1 to 88.161.255.25488.161.255.255131,070
8288.162.0.0/1588.162.0.1 to 88.163.255.25488.163.255.255131,070
8388.164.0.0/1588.164.0.1 to 88.165.255.25488.165.255.255131,070
8488.166.0.0/1588.166.0.1 to 88.167.255.25488.167.255.255131,070
8588.168.0.0/1588.168.0.1 to 88.169.255.25488.169.255.255131,070
8688.170.0.0/1588.170.0.1 to 88.171.255.25488.171.255.255131,070
8788.172.0.0/1588.172.0.1 to 88.173.255.25488.173.255.255131,070
8888.174.0.0/1588.174.0.1 to 88.175.255.25488.175.255.255131,070
8988.176.0.0/1588.176.0.1 to 88.177.255.25488.177.255.255131,070
9088.178.0.0/1588.178.0.1 to 88.179.255.25488.179.255.255131,070
9188.180.0.0/1588.180.0.1 to 88.181.255.25488.181.255.255131,070
9288.182.0.0/1588.182.0.1 to 88.183.255.25488.183.255.255131,070
9388.184.0.0/1588.184.0.1 to 88.185.255.25488.185.255.255131,070
9488.186.0.0/1588.186.0.1 to 88.187.255.25488.187.255.255131,070
9588.188.0.0/1588.188.0.1 to 88.189.255.25488.189.255.255131,070
9688.190.0.0/1588.190.0.1 to 88.191.255.25488.191.255.255131,070
9788.192.0.0/1588.192.0.1 to 88.193.255.25488.193.255.255131,070
9888.194.0.0/1588.194.0.1 to 88.195.255.25488.195.255.255131,070
9988.196.0.0/1588.196.0.1 to 88.197.255.25488.197.255.255131,070
10088.198.0.0/1588.198.0.1 to 88.199.255.25488.199.255.255131,070
10188.200.0.0/1588.200.0.1 to 88.201.255.25488.201.255.255131,070
10288.202.0.0/1588.202.0.1 to 88.203.255.25488.203.255.255131,070
10388.204.0.0/1588.204.0.1 to 88.205.255.25488.205.255.255131,070
10488.206.0.0/1588.206.0.1 to 88.207.255.25488.207.255.255131,070
10588.208.0.0/1588.208.0.1 to 88.209.255.25488.209.255.255131,070
10688.210.0.0/1588.210.0.1 to 88.211.255.25488.211.255.255131,070
10788.212.0.0/1588.212.0.1 to 88.213.255.25488.213.255.255131,070
10888.214.0.0/1588.214.0.1 to 88.215.255.25488.215.255.255131,070
10988.216.0.0/1588.216.0.1 to 88.217.255.25488.217.255.255131,070
11088.218.0.0/1588.218.0.1 to 88.219.255.25488.219.255.255131,070
11188.220.0.0/1588.220.0.1 to 88.221.255.25488.221.255.255131,070
11288.222.0.0/1588.222.0.1 to 88.223.255.25488.223.255.255131,070
11388.224.0.0/1588.224.0.1 to 88.225.255.25488.225.255.255131,070
11488.226.0.0/1588.226.0.1 to 88.227.255.25488.227.255.255131,070
11588.228.0.0/1588.228.0.1 to 88.229.255.25488.229.255.255131,070
11688.230.0.0/1588.230.0.1 to 88.231.255.25488.231.255.255131,070
11788.232.0.0/1588.232.0.1 to 88.233.255.25488.233.255.255131,070
11888.234.0.0/1588.234.0.1 to 88.235.255.25488.235.255.255131,070
11988.236.0.0/1588.236.0.1 to 88.237.255.25488.237.255.255131,070
12088.238.0.0/1588.238.0.1 to 88.239.255.25488.239.255.255131,070
12188.240.0.0/1588.240.0.1 to 88.241.255.25488.241.255.255131,070
12288.242.0.0/1588.242.0.1 to 88.243.255.25488.243.255.255131,070
12388.244.0.0/1588.244.0.1 to 88.245.255.25488.245.255.255131,070
12488.246.0.0/1588.246.0.1 to 88.247.255.25488.247.255.255131,070
12588.248.0.0/1588.248.0.1 to 88.249.255.25488.249.255.255131,070
12688.250.0.0/1588.250.0.1 to 88.251.255.25488.251.255.255131,070
12788.252.0.0/1588.252.0.1 to 88.253.255.25488.253.255.255131,070
12888.254.0.0/1588.254.0.1 to 88.255.255.25488.255.255.255131,070
12989.0.0.0/1589.0.0.1 to 89.1.255.25489.1.255.255131,070
13089.2.0.0/1589.2.0.1 to 89.3.255.25489.3.255.255131,070
13189.4.0.0/1589.4.0.1 to 89.5.255.25489.5.255.255131,070
13289.6.0.0/1589.6.0.1 to 89.7.255.25489.7.255.255131,070
13389.8.0.0/1589.8.0.1 to 89.9.255.25489.9.255.255131,070
13489.10.0.0/1589.10.0.1 to 89.11.255.25489.11.255.255131,070
13589.12.0.0/1589.12.0.1 to 89.13.255.25489.13.255.255131,070
13689.14.0.0/1589.14.0.1 to 89.15.255.25489.15.255.255131,070
13789.16.0.0/1589.16.0.1 to 89.17.255.25489.17.255.255131,070
13889.18.0.0/1589.18.0.1 to 89.19.255.25489.19.255.255131,070
13989.20.0.0/1589.20.0.1 to 89.21.255.25489.21.255.255131,070
14089.22.0.0/1589.22.0.1 to 89.23.255.25489.23.255.255131,070
14189.24.0.0/1589.24.0.1 to 89.25.255.25489.25.255.255131,070
14289.26.0.0/1589.26.0.1 to 89.27.255.25489.27.255.255131,070
14389.28.0.0/1589.28.0.1 to 89.29.255.25489.29.255.255131,070
14489.30.0.0/1589.30.0.1 to 89.31.255.25489.31.255.255131,070
14589.32.0.0/1589.32.0.1 to 89.33.255.25489.33.255.255131,070
14689.34.0.0/1589.34.0.1 to 89.35.255.25489.35.255.255131,070
14789.36.0.0/1589.36.0.1 to 89.37.255.25489.37.255.255131,070
14889.38.0.0/1589.38.0.1 to 89.39.255.25489.39.255.255131,070
14989.40.0.0/1589.40.0.1 to 89.41.255.25489.41.255.255131,070
15089.42.0.0/1589.42.0.1 to 89.43.255.25489.43.255.255131,070
15189.44.0.0/1589.44.0.1 to 89.45.255.25489.45.255.255131,070
15289.46.0.0/1589.46.0.1 to 89.47.255.25489.47.255.255131,070
15389.48.0.0/1589.48.0.1 to 89.49.255.25489.49.255.255131,070
15489.50.0.0/1589.50.0.1 to 89.51.255.25489.51.255.255131,070
15589.52.0.0/1589.52.0.1 to 89.53.255.25489.53.255.255131,070
15689.54.0.0/1589.54.0.1 to 89.55.255.25489.55.255.255131,070
15789.56.0.0/1589.56.0.1 to 89.57.255.25489.57.255.255131,070
15889.58.0.0/1589.58.0.1 to 89.59.255.25489.59.255.255131,070
15989.60.0.0/1589.60.0.1 to 89.61.255.25489.61.255.255131,070
16089.62.0.0/1589.62.0.1 to 89.63.255.25489.63.255.255131,070
16189.64.0.0/1589.64.0.1 to 89.65.255.25489.65.255.255131,070
16289.66.0.0/1589.66.0.1 to 89.67.255.25489.67.255.255131,070
16389.68.0.0/1589.68.0.1 to 89.69.255.25489.69.255.255131,070
16489.70.0.0/1589.70.0.1 to 89.71.255.25489.71.255.255131,070
16589.72.0.0/1589.72.0.1 to 89.73.255.25489.73.255.255131,070
16689.74.0.0/1589.74.0.1 to 89.75.255.25489.75.255.255131,070
16789.76.0.0/1589.76.0.1 to 89.77.255.25489.77.255.255131,070
16889.78.0.0/1589.78.0.1 to 89.79.255.25489.79.255.255131,070
16989.80.0.0/1589.80.0.1 to 89.81.255.25489.81.255.255131,070
17089.82.0.0/1589.82.0.1 to 89.83.255.25489.83.255.255131,070
17189.84.0.0/1589.84.0.1 to 89.85.255.25489.85.255.255131,070
17289.86.0.0/1589.86.0.1 to 89.87.255.25489.87.255.255131,070
17389.88.0.0/1589.88.0.1 to 89.89.255.25489.89.255.255131,070
17489.90.0.0/1589.90.0.1 to 89.91.255.25489.91.255.255131,070
17589.92.0.0/1589.92.0.1 to 89.93.255.25489.93.255.255131,070
17689.94.0.0/1589.94.0.1 to 89.95.255.25489.95.255.255131,070
17789.96.0.0/1589.96.0.1 to 89.97.255.25489.97.255.255131,070
17889.98.0.0/1589.98.0.1 to 89.99.255.25489.99.255.255131,070
17989.100.0.0/1589.100.0.1 to 89.101.255.25489.101.255.255131,070
18089.102.0.0/1589.102.0.1 to 89.103.255.25489.103.255.255131,070
18189.104.0.0/1589.104.0.1 to 89.105.255.25489.105.255.255131,070
18289.106.0.0/1589.106.0.1 to 89.107.255.25489.107.255.255131,070
18389.108.0.0/1589.108.0.1 to 89.109.255.25489.109.255.255131,070
18489.110.0.0/1589.110.0.1 to 89.111.255.25489.111.255.255131,070
18589.112.0.0/1589.112.0.1 to 89.113.255.25489.113.255.255131,070
18689.114.0.0/1589.114.0.1 to 89.115.255.25489.115.255.255131,070
18789.116.0.0/1589.116.0.1 to 89.117.255.25489.117.255.255131,070
18889.118.0.0/1589.118.0.1 to 89.119.255.25489.119.255.255131,070
18989.120.0.0/1589.120.0.1 to 89.121.255.25489.121.255.255131,070
19089.122.0.0/1589.122.0.1 to 89.123.255.25489.123.255.255131,070
19189.124.0.0/1589.124.0.1 to 89.125.255.25489.125.255.255131,070
19289.126.0.0/1589.126.0.1 to 89.127.255.25489.127.255.255131,070
19389.128.0.0/1589.128.0.1 to 89.129.255.25489.129.255.255131,070
19489.130.0.0/1589.130.0.1 to 89.131.255.25489.131.255.255131,070
19589.132.0.0/1589.132.0.1 to 89.133.255.25489.133.255.255131,070
19689.134.0.0/1589.134.0.1 to 89.135.255.25489.135.255.255131,070
19789.136.0.0/1589.136.0.1 to 89.137.255.25489.137.255.255131,070
19889.138.0.0/1589.138.0.1 to 89.139.255.25489.139.255.255131,070
19989.140.0.0/1589.140.0.1 to 89.141.255.25489.141.255.255131,070
20089.142.0.0/1589.142.0.1 to 89.143.255.25489.143.255.255131,070
20189.144.0.0/1589.144.0.1 to 89.145.255.25489.145.255.255131,070
20289.146.0.0/1589.146.0.1 to 89.147.255.25489.147.255.255131,070
20389.148.0.0/1589.148.0.1 to 89.149.255.25489.149.255.255131,070
20489.150.0.0/1589.150.0.1 to 89.151.255.25489.151.255.255131,070
20589.152.0.0/1589.152.0.1 to 89.153.255.25489.153.255.255131,070
20689.154.0.0/1589.154.0.1 to 89.155.255.25489.155.255.255131,070
20789.156.0.0/1589.156.0.1 to 89.157.255.25489.157.255.255131,070
20889.158.0.0/1589.158.0.1 to 89.159.255.25489.159.255.255131,070
20989.160.0.0/1589.160.0.1 to 89.161.255.25489.161.255.255131,070
21089.162.0.0/1589.162.0.1 to 89.163.255.25489.163.255.255131,070
21189.164.0.0/1589.164.0.1 to 89.165.255.25489.165.255.255131,070
21289.166.0.0/1589.166.0.1 to 89.167.255.25489.167.255.255131,070
21389.168.0.0/1589.168.0.1 to 89.169.255.25489.169.255.255131,070
21489.170.0.0/1589.170.0.1 to 89.171.255.25489.171.255.255131,070
21589.172.0.0/1589.172.0.1 to 89.173.255.25489.173.255.255131,070
21689.174.0.0/1589.174.0.1 to 89.175.255.25489.175.255.255131,070
21789.176.0.0/1589.176.0.1 to 89.177.255.25489.177.255.255131,070
21889.178.0.0/1589.178.0.1 to 89.179.255.25489.179.255.255131,070
21989.180.0.0/1589.180.0.1 to 89.181.255.25489.181.255.255131,070
22089.182.0.0/1589.182.0.1 to 89.183.255.25489.183.255.255131,070
22189.184.0.0/1589.184.0.1 to 89.185.255.25489.185.255.255131,070
22289.186.0.0/1589.186.0.1 to 89.187.255.25489.187.255.255131,070
22389.188.0.0/1589.188.0.1 to 89.189.255.25489.189.255.255131,070
22489.190.0.0/1589.190.0.1 to 89.191.255.25489.191.255.255131,070
22589.192.0.0/1589.192.0.1 to 89.193.255.25489.193.255.255131,070
22689.194.0.0/1589.194.0.1 to 89.195.255.25489.195.255.255131,070
22789.196.0.0/1589.196.0.1 to 89.197.255.25489.197.255.255131,070
22889.198.0.0/1589.198.0.1 to 89.199.255.25489.199.255.255131,070
22989.200.0.0/1589.200.0.1 to 89.201.255.25489.201.255.255131,070
23089.202.0.0/1589.202.0.1 to 89.203.255.25489.203.255.255131,070
23189.204.0.0/1589.204.0.1 to 89.205.255.25489.205.255.255131,070
23289.206.0.0/1589.206.0.1 to 89.207.255.25489.207.255.255131,070
23389.208.0.0/1589.208.0.1 to 89.209.255.25489.209.255.255131,070
23489.210.0.0/1589.210.0.1 to 89.211.255.25489.211.255.255131,070
23589.212.0.0/1589.212.0.1 to 89.213.255.25489.213.255.255131,070
23689.214.0.0/1589.214.0.1 to 89.215.255.25489.215.255.255131,070
23789.216.0.0/1589.216.0.1 to 89.217.255.25489.217.255.255131,070
23889.218.0.0/1589.218.0.1 to 89.219.255.25489.219.255.255131,070
23989.220.0.0/1589.220.0.1 to 89.221.255.25489.221.255.255131,070
24089.222.0.0/1589.222.0.1 to 89.223.255.25489.223.255.255131,070
24189.224.0.0/1589.224.0.1 to 89.225.255.25489.225.255.255131,070
24289.226.0.0/1589.226.0.1 to 89.227.255.25489.227.255.255131,070
24389.228.0.0/1589.228.0.1 to 89.229.255.25489.229.255.255131,070
24489.230.0.0/1589.230.0.1 to 89.231.255.25489.231.255.255131,070
24589.232.0.0/1589.232.0.1 to 89.233.255.25489.233.255.255131,070
24689.234.0.0/1589.234.0.1 to 89.235.255.25489.235.255.255131,070
24789.236.0.0/1589.236.0.1 to 89.237.255.25489.237.255.255131,070
24889.238.0.0/1589.238.0.1 to 89.239.255.25489.239.255.255131,070
24989.240.0.0/1589.240.0.1 to 89.241.255.25489.241.255.255131,070
25089.242.0.0/1589.242.0.1 to 89.243.255.25489.243.255.255131,070
25189.244.0.0/1589.244.0.1 to 89.245.255.25489.245.255.255131,070
25289.246.0.0/1589.246.0.1 to 89.247.255.25489.247.255.255131,070
25389.248.0.0/1589.248.0.1 to 89.249.255.25489.249.255.255131,070
25489.250.0.0/1589.250.0.1 to 89.251.255.25489.251.255.255131,070
25589.252.0.0/1589.252.0.1 to 89.253.255.25489.253.255.255131,070
25689.254.0.0/1589.254.0.1 to 89.255.255.25489.255.255.255131,070

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.