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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.

Network83.232.0.0/15
Usable hosts131,070
Subnet mask255.254.0.0
Addresses131,072
Network address
83.232.0.0
Broadcast address
83.233.255.255
First usable
83.232.0.1
Last usable
83.233.255.254
Usable hosts
131,070 (131,072 less the network and broadcast addresses)
Subnet mask
255.254.0.0
Wildcard mask
0.1.255.255 (Cisco ACLs, OSPF)
Prefix length
/15
Type
Public public
Old class
A (default /8)
As numbers
Hex 53E80000 · Integer 1407713280 to 1407844351
Reverse DNS zones
232.83.in-addr.arpa
233.83.in-addr.arpa
/15 is not on a 8-bit boundary, so it takes 2 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010011.11101000.00000000.0000000083.232.0.0
Subnet mask11111111.11111110.00000000.00000000255.254.0.0
Network01010011.11101000.00000000.0000000083.232.0.0
Broadcast01010011.11101001.11111111.1111111183.233.255.255
Split into smaller subnets/24
/16 (2)/17 (4)/18 (8)/19 (16)/20 (32)/21 (64)/22 (128)/23 (256)/24 (512)/25 (1,024)/26 (2,048)/27 (4,096)

83.232.0.0/15 makes 512 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
183.232.0.0/2483.232.0.1 to 83.232.0.25483.232.0.255254
283.232.1.0/2483.232.1.1 to 83.232.1.25483.232.1.255254
383.232.2.0/2483.232.2.1 to 83.232.2.25483.232.2.255254
483.232.3.0/2483.232.3.1 to 83.232.3.25483.232.3.255254
583.232.4.0/2483.232.4.1 to 83.232.4.25483.232.4.255254
683.232.5.0/2483.232.5.1 to 83.232.5.25483.232.5.255254
783.232.6.0/2483.232.6.1 to 83.232.6.25483.232.6.255254
883.232.7.0/2483.232.7.1 to 83.232.7.25483.232.7.255254
983.232.8.0/2483.232.8.1 to 83.232.8.25483.232.8.255254
1083.232.9.0/2483.232.9.1 to 83.232.9.25483.232.9.255254
1183.232.10.0/2483.232.10.1 to 83.232.10.25483.232.10.255254
1283.232.11.0/2483.232.11.1 to 83.232.11.25483.232.11.255254
1383.232.12.0/2483.232.12.1 to 83.232.12.25483.232.12.255254
1483.232.13.0/2483.232.13.1 to 83.232.13.25483.232.13.255254
1583.232.14.0/2483.232.14.1 to 83.232.14.25483.232.14.255254
1683.232.15.0/2483.232.15.1 to 83.232.15.25483.232.15.255254
1783.232.16.0/2483.232.16.1 to 83.232.16.25483.232.16.255254
1883.232.17.0/2483.232.17.1 to 83.232.17.25483.232.17.255254
1983.232.18.0/2483.232.18.1 to 83.232.18.25483.232.18.255254
2083.232.19.0/2483.232.19.1 to 83.232.19.25483.232.19.255254
2183.232.20.0/2483.232.20.1 to 83.232.20.25483.232.20.255254
2283.232.21.0/2483.232.21.1 to 83.232.21.25483.232.21.255254
2383.232.22.0/2483.232.22.1 to 83.232.22.25483.232.22.255254
2483.232.23.0/2483.232.23.1 to 83.232.23.25483.232.23.255254
2583.232.24.0/2483.232.24.1 to 83.232.24.25483.232.24.255254
2683.232.25.0/2483.232.25.1 to 83.232.25.25483.232.25.255254
2783.232.26.0/2483.232.26.1 to 83.232.26.25483.232.26.255254
2883.232.27.0/2483.232.27.1 to 83.232.27.25483.232.27.255254
2983.232.28.0/2483.232.28.1 to 83.232.28.25483.232.28.255254
3083.232.29.0/2483.232.29.1 to 83.232.29.25483.232.29.255254
3183.232.30.0/2483.232.30.1 to 83.232.30.25483.232.30.255254
3283.232.31.0/2483.232.31.1 to 83.232.31.25483.232.31.255254
3383.232.32.0/2483.232.32.1 to 83.232.32.25483.232.32.255254
3483.232.33.0/2483.232.33.1 to 83.232.33.25483.232.33.255254
3583.232.34.0/2483.232.34.1 to 83.232.34.25483.232.34.255254
3683.232.35.0/2483.232.35.1 to 83.232.35.25483.232.35.255254
3783.232.36.0/2483.232.36.1 to 83.232.36.25483.232.36.255254
3883.232.37.0/2483.232.37.1 to 83.232.37.25483.232.37.255254
3983.232.38.0/2483.232.38.1 to 83.232.38.25483.232.38.255254
4083.232.39.0/2483.232.39.1 to 83.232.39.25483.232.39.255254
4183.232.40.0/2483.232.40.1 to 83.232.40.25483.232.40.255254
4283.232.41.0/2483.232.41.1 to 83.232.41.25483.232.41.255254
4383.232.42.0/2483.232.42.1 to 83.232.42.25483.232.42.255254
4483.232.43.0/2483.232.43.1 to 83.232.43.25483.232.43.255254
4583.232.44.0/2483.232.44.1 to 83.232.44.25483.232.44.255254
4683.232.45.0/2483.232.45.1 to 83.232.45.25483.232.45.255254
4783.232.46.0/2483.232.46.1 to 83.232.46.25483.232.46.255254
4883.232.47.0/2483.232.47.1 to 83.232.47.25483.232.47.255254
4983.232.48.0/2483.232.48.1 to 83.232.48.25483.232.48.255254
5083.232.49.0/2483.232.49.1 to 83.232.49.25483.232.49.255254
5183.232.50.0/2483.232.50.1 to 83.232.50.25483.232.50.255254
5283.232.51.0/2483.232.51.1 to 83.232.51.25483.232.51.255254
5383.232.52.0/2483.232.52.1 to 83.232.52.25483.232.52.255254
5483.232.53.0/2483.232.53.1 to 83.232.53.25483.232.53.255254
5583.232.54.0/2483.232.54.1 to 83.232.54.25483.232.54.255254
5683.232.55.0/2483.232.55.1 to 83.232.55.25483.232.55.255254
5783.232.56.0/2483.232.56.1 to 83.232.56.25483.232.56.255254
5883.232.57.0/2483.232.57.1 to 83.232.57.25483.232.57.255254
5983.232.58.0/2483.232.58.1 to 83.232.58.25483.232.58.255254
6083.232.59.0/2483.232.59.1 to 83.232.59.25483.232.59.255254
6183.232.60.0/2483.232.60.1 to 83.232.60.25483.232.60.255254
6283.232.61.0/2483.232.61.1 to 83.232.61.25483.232.61.255254
6383.232.62.0/2483.232.62.1 to 83.232.62.25483.232.62.255254
6483.232.63.0/2483.232.63.1 to 83.232.63.25483.232.63.255254
6583.232.64.0/2483.232.64.1 to 83.232.64.25483.232.64.255254
6683.232.65.0/2483.232.65.1 to 83.232.65.25483.232.65.255254
6783.232.66.0/2483.232.66.1 to 83.232.66.25483.232.66.255254
6883.232.67.0/2483.232.67.1 to 83.232.67.25483.232.67.255254
6983.232.68.0/2483.232.68.1 to 83.232.68.25483.232.68.255254
7083.232.69.0/2483.232.69.1 to 83.232.69.25483.232.69.255254
7183.232.70.0/2483.232.70.1 to 83.232.70.25483.232.70.255254
7283.232.71.0/2483.232.71.1 to 83.232.71.25483.232.71.255254
7383.232.72.0/2483.232.72.1 to 83.232.72.25483.232.72.255254
7483.232.73.0/2483.232.73.1 to 83.232.73.25483.232.73.255254
7583.232.74.0/2483.232.74.1 to 83.232.74.25483.232.74.255254
7683.232.75.0/2483.232.75.1 to 83.232.75.25483.232.75.255254
7783.232.76.0/2483.232.76.1 to 83.232.76.25483.232.76.255254
7883.232.77.0/2483.232.77.1 to 83.232.77.25483.232.77.255254
7983.232.78.0/2483.232.78.1 to 83.232.78.25483.232.78.255254
8083.232.79.0/2483.232.79.1 to 83.232.79.25483.232.79.255254
8183.232.80.0/2483.232.80.1 to 83.232.80.25483.232.80.255254
8283.232.81.0/2483.232.81.1 to 83.232.81.25483.232.81.255254
8383.232.82.0/2483.232.82.1 to 83.232.82.25483.232.82.255254
8483.232.83.0/2483.232.83.1 to 83.232.83.25483.232.83.255254
8583.232.84.0/2483.232.84.1 to 83.232.84.25483.232.84.255254
8683.232.85.0/2483.232.85.1 to 83.232.85.25483.232.85.255254
8783.232.86.0/2483.232.86.1 to 83.232.86.25483.232.86.255254
8883.232.87.0/2483.232.87.1 to 83.232.87.25483.232.87.255254
8983.232.88.0/2483.232.88.1 to 83.232.88.25483.232.88.255254
9083.232.89.0/2483.232.89.1 to 83.232.89.25483.232.89.255254
9183.232.90.0/2483.232.90.1 to 83.232.90.25483.232.90.255254
9283.232.91.0/2483.232.91.1 to 83.232.91.25483.232.91.255254
9383.232.92.0/2483.232.92.1 to 83.232.92.25483.232.92.255254
9483.232.93.0/2483.232.93.1 to 83.232.93.25483.232.93.255254
9583.232.94.0/2483.232.94.1 to 83.232.94.25483.232.94.255254
9683.232.95.0/2483.232.95.1 to 83.232.95.25483.232.95.255254
9783.232.96.0/2483.232.96.1 to 83.232.96.25483.232.96.255254
9883.232.97.0/2483.232.97.1 to 83.232.97.25483.232.97.255254
9983.232.98.0/2483.232.98.1 to 83.232.98.25483.232.98.255254
10083.232.99.0/2483.232.99.1 to 83.232.99.25483.232.99.255254
10183.232.100.0/2483.232.100.1 to 83.232.100.25483.232.100.255254
10283.232.101.0/2483.232.101.1 to 83.232.101.25483.232.101.255254
10383.232.102.0/2483.232.102.1 to 83.232.102.25483.232.102.255254
10483.232.103.0/2483.232.103.1 to 83.232.103.25483.232.103.255254
10583.232.104.0/2483.232.104.1 to 83.232.104.25483.232.104.255254
10683.232.105.0/2483.232.105.1 to 83.232.105.25483.232.105.255254
10783.232.106.0/2483.232.106.1 to 83.232.106.25483.232.106.255254
10883.232.107.0/2483.232.107.1 to 83.232.107.25483.232.107.255254
10983.232.108.0/2483.232.108.1 to 83.232.108.25483.232.108.255254
11083.232.109.0/2483.232.109.1 to 83.232.109.25483.232.109.255254
11183.232.110.0/2483.232.110.1 to 83.232.110.25483.232.110.255254
11283.232.111.0/2483.232.111.1 to 83.232.111.25483.232.111.255254
11383.232.112.0/2483.232.112.1 to 83.232.112.25483.232.112.255254
11483.232.113.0/2483.232.113.1 to 83.232.113.25483.232.113.255254
11583.232.114.0/2483.232.114.1 to 83.232.114.25483.232.114.255254
11683.232.115.0/2483.232.115.1 to 83.232.115.25483.232.115.255254
11783.232.116.0/2483.232.116.1 to 83.232.116.25483.232.116.255254
11883.232.117.0/2483.232.117.1 to 83.232.117.25483.232.117.255254
11983.232.118.0/2483.232.118.1 to 83.232.118.25483.232.118.255254
12083.232.119.0/2483.232.119.1 to 83.232.119.25483.232.119.255254
12183.232.120.0/2483.232.120.1 to 83.232.120.25483.232.120.255254
12283.232.121.0/2483.232.121.1 to 83.232.121.25483.232.121.255254
12383.232.122.0/2483.232.122.1 to 83.232.122.25483.232.122.255254
12483.232.123.0/2483.232.123.1 to 83.232.123.25483.232.123.255254
12583.232.124.0/2483.232.124.1 to 83.232.124.25483.232.124.255254
12683.232.125.0/2483.232.125.1 to 83.232.125.25483.232.125.255254
12783.232.126.0/2483.232.126.1 to 83.232.126.25483.232.126.255254
12883.232.127.0/2483.232.127.1 to 83.232.127.25483.232.127.255254
12983.232.128.0/2483.232.128.1 to 83.232.128.25483.232.128.255254
13083.232.129.0/2483.232.129.1 to 83.232.129.25483.232.129.255254
13183.232.130.0/2483.232.130.1 to 83.232.130.25483.232.130.255254
13283.232.131.0/2483.232.131.1 to 83.232.131.25483.232.131.255254
13383.232.132.0/2483.232.132.1 to 83.232.132.25483.232.132.255254
13483.232.133.0/2483.232.133.1 to 83.232.133.25483.232.133.255254
13583.232.134.0/2483.232.134.1 to 83.232.134.25483.232.134.255254
13683.232.135.0/2483.232.135.1 to 83.232.135.25483.232.135.255254
13783.232.136.0/2483.232.136.1 to 83.232.136.25483.232.136.255254
13883.232.137.0/2483.232.137.1 to 83.232.137.25483.232.137.255254
13983.232.138.0/2483.232.138.1 to 83.232.138.25483.232.138.255254
14083.232.139.0/2483.232.139.1 to 83.232.139.25483.232.139.255254
14183.232.140.0/2483.232.140.1 to 83.232.140.25483.232.140.255254
14283.232.141.0/2483.232.141.1 to 83.232.141.25483.232.141.255254
14383.232.142.0/2483.232.142.1 to 83.232.142.25483.232.142.255254
14483.232.143.0/2483.232.143.1 to 83.232.143.25483.232.143.255254
14583.232.144.0/2483.232.144.1 to 83.232.144.25483.232.144.255254
14683.232.145.0/2483.232.145.1 to 83.232.145.25483.232.145.255254
14783.232.146.0/2483.232.146.1 to 83.232.146.25483.232.146.255254
14883.232.147.0/2483.232.147.1 to 83.232.147.25483.232.147.255254
14983.232.148.0/2483.232.148.1 to 83.232.148.25483.232.148.255254
15083.232.149.0/2483.232.149.1 to 83.232.149.25483.232.149.255254
15183.232.150.0/2483.232.150.1 to 83.232.150.25483.232.150.255254
15283.232.151.0/2483.232.151.1 to 83.232.151.25483.232.151.255254
15383.232.152.0/2483.232.152.1 to 83.232.152.25483.232.152.255254
15483.232.153.0/2483.232.153.1 to 83.232.153.25483.232.153.255254
15583.232.154.0/2483.232.154.1 to 83.232.154.25483.232.154.255254
15683.232.155.0/2483.232.155.1 to 83.232.155.25483.232.155.255254
15783.232.156.0/2483.232.156.1 to 83.232.156.25483.232.156.255254
15883.232.157.0/2483.232.157.1 to 83.232.157.25483.232.157.255254
15983.232.158.0/2483.232.158.1 to 83.232.158.25483.232.158.255254
16083.232.159.0/2483.232.159.1 to 83.232.159.25483.232.159.255254
16183.232.160.0/2483.232.160.1 to 83.232.160.25483.232.160.255254
16283.232.161.0/2483.232.161.1 to 83.232.161.25483.232.161.255254
16383.232.162.0/2483.232.162.1 to 83.232.162.25483.232.162.255254
16483.232.163.0/2483.232.163.1 to 83.232.163.25483.232.163.255254
16583.232.164.0/2483.232.164.1 to 83.232.164.25483.232.164.255254
16683.232.165.0/2483.232.165.1 to 83.232.165.25483.232.165.255254
16783.232.166.0/2483.232.166.1 to 83.232.166.25483.232.166.255254
16883.232.167.0/2483.232.167.1 to 83.232.167.25483.232.167.255254
16983.232.168.0/2483.232.168.1 to 83.232.168.25483.232.168.255254
17083.232.169.0/2483.232.169.1 to 83.232.169.25483.232.169.255254
17183.232.170.0/2483.232.170.1 to 83.232.170.25483.232.170.255254
17283.232.171.0/2483.232.171.1 to 83.232.171.25483.232.171.255254
17383.232.172.0/2483.232.172.1 to 83.232.172.25483.232.172.255254
17483.232.173.0/2483.232.173.1 to 83.232.173.25483.232.173.255254
17583.232.174.0/2483.232.174.1 to 83.232.174.25483.232.174.255254
17683.232.175.0/2483.232.175.1 to 83.232.175.25483.232.175.255254
17783.232.176.0/2483.232.176.1 to 83.232.176.25483.232.176.255254
17883.232.177.0/2483.232.177.1 to 83.232.177.25483.232.177.255254
17983.232.178.0/2483.232.178.1 to 83.232.178.25483.232.178.255254
18083.232.179.0/2483.232.179.1 to 83.232.179.25483.232.179.255254
18183.232.180.0/2483.232.180.1 to 83.232.180.25483.232.180.255254
18283.232.181.0/2483.232.181.1 to 83.232.181.25483.232.181.255254
18383.232.182.0/2483.232.182.1 to 83.232.182.25483.232.182.255254
18483.232.183.0/2483.232.183.1 to 83.232.183.25483.232.183.255254
18583.232.184.0/2483.232.184.1 to 83.232.184.25483.232.184.255254
18683.232.185.0/2483.232.185.1 to 83.232.185.25483.232.185.255254
18783.232.186.0/2483.232.186.1 to 83.232.186.25483.232.186.255254
18883.232.187.0/2483.232.187.1 to 83.232.187.25483.232.187.255254
18983.232.188.0/2483.232.188.1 to 83.232.188.25483.232.188.255254
19083.232.189.0/2483.232.189.1 to 83.232.189.25483.232.189.255254
19183.232.190.0/2483.232.190.1 to 83.232.190.25483.232.190.255254
19283.232.191.0/2483.232.191.1 to 83.232.191.25483.232.191.255254
19383.232.192.0/2483.232.192.1 to 83.232.192.25483.232.192.255254
19483.232.193.0/2483.232.193.1 to 83.232.193.25483.232.193.255254
19583.232.194.0/2483.232.194.1 to 83.232.194.25483.232.194.255254
19683.232.195.0/2483.232.195.1 to 83.232.195.25483.232.195.255254
19783.232.196.0/2483.232.196.1 to 83.232.196.25483.232.196.255254
19883.232.197.0/2483.232.197.1 to 83.232.197.25483.232.197.255254
19983.232.198.0/2483.232.198.1 to 83.232.198.25483.232.198.255254
20083.232.199.0/2483.232.199.1 to 83.232.199.25483.232.199.255254
20183.232.200.0/2483.232.200.1 to 83.232.200.25483.232.200.255254
20283.232.201.0/2483.232.201.1 to 83.232.201.25483.232.201.255254
20383.232.202.0/2483.232.202.1 to 83.232.202.25483.232.202.255254
20483.232.203.0/2483.232.203.1 to 83.232.203.25483.232.203.255254
20583.232.204.0/2483.232.204.1 to 83.232.204.25483.232.204.255254
20683.232.205.0/2483.232.205.1 to 83.232.205.25483.232.205.255254
20783.232.206.0/2483.232.206.1 to 83.232.206.25483.232.206.255254
20883.232.207.0/2483.232.207.1 to 83.232.207.25483.232.207.255254
20983.232.208.0/2483.232.208.1 to 83.232.208.25483.232.208.255254
21083.232.209.0/2483.232.209.1 to 83.232.209.25483.232.209.255254
21183.232.210.0/2483.232.210.1 to 83.232.210.25483.232.210.255254
21283.232.211.0/2483.232.211.1 to 83.232.211.25483.232.211.255254
21383.232.212.0/2483.232.212.1 to 83.232.212.25483.232.212.255254
21483.232.213.0/2483.232.213.1 to 83.232.213.25483.232.213.255254
21583.232.214.0/2483.232.214.1 to 83.232.214.25483.232.214.255254
21683.232.215.0/2483.232.215.1 to 83.232.215.25483.232.215.255254
21783.232.216.0/2483.232.216.1 to 83.232.216.25483.232.216.255254
21883.232.217.0/2483.232.217.1 to 83.232.217.25483.232.217.255254
21983.232.218.0/2483.232.218.1 to 83.232.218.25483.232.218.255254
22083.232.219.0/2483.232.219.1 to 83.232.219.25483.232.219.255254
22183.232.220.0/2483.232.220.1 to 83.232.220.25483.232.220.255254
22283.232.221.0/2483.232.221.1 to 83.232.221.25483.232.221.255254
22383.232.222.0/2483.232.222.1 to 83.232.222.25483.232.222.255254
22483.232.223.0/2483.232.223.1 to 83.232.223.25483.232.223.255254
22583.232.224.0/2483.232.224.1 to 83.232.224.25483.232.224.255254
22683.232.225.0/2483.232.225.1 to 83.232.225.25483.232.225.255254
22783.232.226.0/2483.232.226.1 to 83.232.226.25483.232.226.255254
22883.232.227.0/2483.232.227.1 to 83.232.227.25483.232.227.255254
22983.232.228.0/2483.232.228.1 to 83.232.228.25483.232.228.255254
23083.232.229.0/2483.232.229.1 to 83.232.229.25483.232.229.255254
23183.232.230.0/2483.232.230.1 to 83.232.230.25483.232.230.255254
23283.232.231.0/2483.232.231.1 to 83.232.231.25483.232.231.255254
23383.232.232.0/2483.232.232.1 to 83.232.232.25483.232.232.255254
23483.232.233.0/2483.232.233.1 to 83.232.233.25483.232.233.255254
23583.232.234.0/2483.232.234.1 to 83.232.234.25483.232.234.255254
23683.232.235.0/2483.232.235.1 to 83.232.235.25483.232.235.255254
23783.232.236.0/2483.232.236.1 to 83.232.236.25483.232.236.255254
23883.232.237.0/2483.232.237.1 to 83.232.237.25483.232.237.255254
23983.232.238.0/2483.232.238.1 to 83.232.238.25483.232.238.255254
24083.232.239.0/2483.232.239.1 to 83.232.239.25483.232.239.255254
24183.232.240.0/2483.232.240.1 to 83.232.240.25483.232.240.255254
24283.232.241.0/2483.232.241.1 to 83.232.241.25483.232.241.255254
24383.232.242.0/2483.232.242.1 to 83.232.242.25483.232.242.255254
24483.232.243.0/2483.232.243.1 to 83.232.243.25483.232.243.255254
24583.232.244.0/2483.232.244.1 to 83.232.244.25483.232.244.255254
24683.232.245.0/2483.232.245.1 to 83.232.245.25483.232.245.255254
24783.232.246.0/2483.232.246.1 to 83.232.246.25483.232.246.255254
24883.232.247.0/2483.232.247.1 to 83.232.247.25483.232.247.255254
24983.232.248.0/2483.232.248.1 to 83.232.248.25483.232.248.255254
25083.232.249.0/2483.232.249.1 to 83.232.249.25483.232.249.255254
25183.232.250.0/2483.232.250.1 to 83.232.250.25483.232.250.255254
25283.232.251.0/2483.232.251.1 to 83.232.251.25483.232.251.255254
25383.232.252.0/2483.232.252.1 to 83.232.252.25483.232.252.255254
25483.232.253.0/2483.232.253.1 to 83.232.253.25483.232.253.255254
25583.232.254.0/2483.232.254.1 to 83.232.254.25483.232.254.255254
25683.232.255.0/2483.232.255.1 to 83.232.255.25483.232.255.255254

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

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.