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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.

Network83.56.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
83.56.0.0
Broadcast address
83.63.255.255
First usable
83.56.0.1
Last usable
83.63.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 53380000 · Integer 1396178944 to 1396703231
Reverse DNS zones
56.83.in-addr.arpa
57.83.in-addr.arpa
58.83.in-addr.arpa
59.83.in-addr.arpa
60.83.in-addr.arpa
61.83.in-addr.arpa
62.83.in-addr.arpa
63.83.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010011.00111000.00000000.0000000083.56.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network01010011.00111000.00000000.0000000083.56.0.0
Broadcast01010011.00111111.11111111.1111111183.63.255.255
Split into smaller subnets/22
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

83.56.0.0/13 makes 512 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
183.56.0.0/2283.56.0.1 to 83.56.3.25483.56.3.2551,022
283.56.4.0/2283.56.4.1 to 83.56.7.25483.56.7.2551,022
383.56.8.0/2283.56.8.1 to 83.56.11.25483.56.11.2551,022
483.56.12.0/2283.56.12.1 to 83.56.15.25483.56.15.2551,022
583.56.16.0/2283.56.16.1 to 83.56.19.25483.56.19.2551,022
683.56.20.0/2283.56.20.1 to 83.56.23.25483.56.23.2551,022
783.56.24.0/2283.56.24.1 to 83.56.27.25483.56.27.2551,022
883.56.28.0/2283.56.28.1 to 83.56.31.25483.56.31.2551,022
983.56.32.0/2283.56.32.1 to 83.56.35.25483.56.35.2551,022
1083.56.36.0/2283.56.36.1 to 83.56.39.25483.56.39.2551,022
1183.56.40.0/2283.56.40.1 to 83.56.43.25483.56.43.2551,022
1283.56.44.0/2283.56.44.1 to 83.56.47.25483.56.47.2551,022
1383.56.48.0/2283.56.48.1 to 83.56.51.25483.56.51.2551,022
1483.56.52.0/2283.56.52.1 to 83.56.55.25483.56.55.2551,022
1583.56.56.0/2283.56.56.1 to 83.56.59.25483.56.59.2551,022
1683.56.60.0/2283.56.60.1 to 83.56.63.25483.56.63.2551,022
1783.56.64.0/2283.56.64.1 to 83.56.67.25483.56.67.2551,022
1883.56.68.0/2283.56.68.1 to 83.56.71.25483.56.71.2551,022
1983.56.72.0/2283.56.72.1 to 83.56.75.25483.56.75.2551,022
2083.56.76.0/2283.56.76.1 to 83.56.79.25483.56.79.2551,022
2183.56.80.0/2283.56.80.1 to 83.56.83.25483.56.83.2551,022
2283.56.84.0/2283.56.84.1 to 83.56.87.25483.56.87.2551,022
2383.56.88.0/2283.56.88.1 to 83.56.91.25483.56.91.2551,022
2483.56.92.0/2283.56.92.1 to 83.56.95.25483.56.95.2551,022
2583.56.96.0/2283.56.96.1 to 83.56.99.25483.56.99.2551,022
2683.56.100.0/2283.56.100.1 to 83.56.103.25483.56.103.2551,022
2783.56.104.0/2283.56.104.1 to 83.56.107.25483.56.107.2551,022
2883.56.108.0/2283.56.108.1 to 83.56.111.25483.56.111.2551,022
2983.56.112.0/2283.56.112.1 to 83.56.115.25483.56.115.2551,022
3083.56.116.0/2283.56.116.1 to 83.56.119.25483.56.119.2551,022
3183.56.120.0/2283.56.120.1 to 83.56.123.25483.56.123.2551,022
3283.56.124.0/2283.56.124.1 to 83.56.127.25483.56.127.2551,022
3383.56.128.0/2283.56.128.1 to 83.56.131.25483.56.131.2551,022
3483.56.132.0/2283.56.132.1 to 83.56.135.25483.56.135.2551,022
3583.56.136.0/2283.56.136.1 to 83.56.139.25483.56.139.2551,022
3683.56.140.0/2283.56.140.1 to 83.56.143.25483.56.143.2551,022
3783.56.144.0/2283.56.144.1 to 83.56.147.25483.56.147.2551,022
3883.56.148.0/2283.56.148.1 to 83.56.151.25483.56.151.2551,022
3983.56.152.0/2283.56.152.1 to 83.56.155.25483.56.155.2551,022
4083.56.156.0/2283.56.156.1 to 83.56.159.25483.56.159.2551,022
4183.56.160.0/2283.56.160.1 to 83.56.163.25483.56.163.2551,022
4283.56.164.0/2283.56.164.1 to 83.56.167.25483.56.167.2551,022
4383.56.168.0/2283.56.168.1 to 83.56.171.25483.56.171.2551,022
4483.56.172.0/2283.56.172.1 to 83.56.175.25483.56.175.2551,022
4583.56.176.0/2283.56.176.1 to 83.56.179.25483.56.179.2551,022
4683.56.180.0/2283.56.180.1 to 83.56.183.25483.56.183.2551,022
4783.56.184.0/2283.56.184.1 to 83.56.187.25483.56.187.2551,022
4883.56.188.0/2283.56.188.1 to 83.56.191.25483.56.191.2551,022
4983.56.192.0/2283.56.192.1 to 83.56.195.25483.56.195.2551,022
5083.56.196.0/2283.56.196.1 to 83.56.199.25483.56.199.2551,022
5183.56.200.0/2283.56.200.1 to 83.56.203.25483.56.203.2551,022
5283.56.204.0/2283.56.204.1 to 83.56.207.25483.56.207.2551,022
5383.56.208.0/2283.56.208.1 to 83.56.211.25483.56.211.2551,022
5483.56.212.0/2283.56.212.1 to 83.56.215.25483.56.215.2551,022
5583.56.216.0/2283.56.216.1 to 83.56.219.25483.56.219.2551,022
5683.56.220.0/2283.56.220.1 to 83.56.223.25483.56.223.2551,022
5783.56.224.0/2283.56.224.1 to 83.56.227.25483.56.227.2551,022
5883.56.228.0/2283.56.228.1 to 83.56.231.25483.56.231.2551,022
5983.56.232.0/2283.56.232.1 to 83.56.235.25483.56.235.2551,022
6083.56.236.0/2283.56.236.1 to 83.56.239.25483.56.239.2551,022
6183.56.240.0/2283.56.240.1 to 83.56.243.25483.56.243.2551,022
6283.56.244.0/2283.56.244.1 to 83.56.247.25483.56.247.2551,022
6383.56.248.0/2283.56.248.1 to 83.56.251.25483.56.251.2551,022
6483.56.252.0/2283.56.252.1 to 83.56.255.25483.56.255.2551,022
6583.57.0.0/2283.57.0.1 to 83.57.3.25483.57.3.2551,022
6683.57.4.0/2283.57.4.1 to 83.57.7.25483.57.7.2551,022
6783.57.8.0/2283.57.8.1 to 83.57.11.25483.57.11.2551,022
6883.57.12.0/2283.57.12.1 to 83.57.15.25483.57.15.2551,022
6983.57.16.0/2283.57.16.1 to 83.57.19.25483.57.19.2551,022
7083.57.20.0/2283.57.20.1 to 83.57.23.25483.57.23.2551,022
7183.57.24.0/2283.57.24.1 to 83.57.27.25483.57.27.2551,022
7283.57.28.0/2283.57.28.1 to 83.57.31.25483.57.31.2551,022
7383.57.32.0/2283.57.32.1 to 83.57.35.25483.57.35.2551,022
7483.57.36.0/2283.57.36.1 to 83.57.39.25483.57.39.2551,022
7583.57.40.0/2283.57.40.1 to 83.57.43.25483.57.43.2551,022
7683.57.44.0/2283.57.44.1 to 83.57.47.25483.57.47.2551,022
7783.57.48.0/2283.57.48.1 to 83.57.51.25483.57.51.2551,022
7883.57.52.0/2283.57.52.1 to 83.57.55.25483.57.55.2551,022
7983.57.56.0/2283.57.56.1 to 83.57.59.25483.57.59.2551,022
8083.57.60.0/2283.57.60.1 to 83.57.63.25483.57.63.2551,022
8183.57.64.0/2283.57.64.1 to 83.57.67.25483.57.67.2551,022
8283.57.68.0/2283.57.68.1 to 83.57.71.25483.57.71.2551,022
8383.57.72.0/2283.57.72.1 to 83.57.75.25483.57.75.2551,022
8483.57.76.0/2283.57.76.1 to 83.57.79.25483.57.79.2551,022
8583.57.80.0/2283.57.80.1 to 83.57.83.25483.57.83.2551,022
8683.57.84.0/2283.57.84.1 to 83.57.87.25483.57.87.2551,022
8783.57.88.0/2283.57.88.1 to 83.57.91.25483.57.91.2551,022
8883.57.92.0/2283.57.92.1 to 83.57.95.25483.57.95.2551,022
8983.57.96.0/2283.57.96.1 to 83.57.99.25483.57.99.2551,022
9083.57.100.0/2283.57.100.1 to 83.57.103.25483.57.103.2551,022
9183.57.104.0/2283.57.104.1 to 83.57.107.25483.57.107.2551,022
9283.57.108.0/2283.57.108.1 to 83.57.111.25483.57.111.2551,022
9383.57.112.0/2283.57.112.1 to 83.57.115.25483.57.115.2551,022
9483.57.116.0/2283.57.116.1 to 83.57.119.25483.57.119.2551,022
9583.57.120.0/2283.57.120.1 to 83.57.123.25483.57.123.2551,022
9683.57.124.0/2283.57.124.1 to 83.57.127.25483.57.127.2551,022
9783.57.128.0/2283.57.128.1 to 83.57.131.25483.57.131.2551,022
9883.57.132.0/2283.57.132.1 to 83.57.135.25483.57.135.2551,022
9983.57.136.0/2283.57.136.1 to 83.57.139.25483.57.139.2551,022
10083.57.140.0/2283.57.140.1 to 83.57.143.25483.57.143.2551,022
10183.57.144.0/2283.57.144.1 to 83.57.147.25483.57.147.2551,022
10283.57.148.0/2283.57.148.1 to 83.57.151.25483.57.151.2551,022
10383.57.152.0/2283.57.152.1 to 83.57.155.25483.57.155.2551,022
10483.57.156.0/2283.57.156.1 to 83.57.159.25483.57.159.2551,022
10583.57.160.0/2283.57.160.1 to 83.57.163.25483.57.163.2551,022
10683.57.164.0/2283.57.164.1 to 83.57.167.25483.57.167.2551,022
10783.57.168.0/2283.57.168.1 to 83.57.171.25483.57.171.2551,022
10883.57.172.0/2283.57.172.1 to 83.57.175.25483.57.175.2551,022
10983.57.176.0/2283.57.176.1 to 83.57.179.25483.57.179.2551,022
11083.57.180.0/2283.57.180.1 to 83.57.183.25483.57.183.2551,022
11183.57.184.0/2283.57.184.1 to 83.57.187.25483.57.187.2551,022
11283.57.188.0/2283.57.188.1 to 83.57.191.25483.57.191.2551,022
11383.57.192.0/2283.57.192.1 to 83.57.195.25483.57.195.2551,022
11483.57.196.0/2283.57.196.1 to 83.57.199.25483.57.199.2551,022
11583.57.200.0/2283.57.200.1 to 83.57.203.25483.57.203.2551,022
11683.57.204.0/2283.57.204.1 to 83.57.207.25483.57.207.2551,022
11783.57.208.0/2283.57.208.1 to 83.57.211.25483.57.211.2551,022
11883.57.212.0/2283.57.212.1 to 83.57.215.25483.57.215.2551,022
11983.57.216.0/2283.57.216.1 to 83.57.219.25483.57.219.2551,022
12083.57.220.0/2283.57.220.1 to 83.57.223.25483.57.223.2551,022
12183.57.224.0/2283.57.224.1 to 83.57.227.25483.57.227.2551,022
12283.57.228.0/2283.57.228.1 to 83.57.231.25483.57.231.2551,022
12383.57.232.0/2283.57.232.1 to 83.57.235.25483.57.235.2551,022
12483.57.236.0/2283.57.236.1 to 83.57.239.25483.57.239.2551,022
12583.57.240.0/2283.57.240.1 to 83.57.243.25483.57.243.2551,022
12683.57.244.0/2283.57.244.1 to 83.57.247.25483.57.247.2551,022
12783.57.248.0/2283.57.248.1 to 83.57.251.25483.57.251.2551,022
12883.57.252.0/2283.57.252.1 to 83.57.255.25483.57.255.2551,022
12983.58.0.0/2283.58.0.1 to 83.58.3.25483.58.3.2551,022
13083.58.4.0/2283.58.4.1 to 83.58.7.25483.58.7.2551,022
13183.58.8.0/2283.58.8.1 to 83.58.11.25483.58.11.2551,022
13283.58.12.0/2283.58.12.1 to 83.58.15.25483.58.15.2551,022
13383.58.16.0/2283.58.16.1 to 83.58.19.25483.58.19.2551,022
13483.58.20.0/2283.58.20.1 to 83.58.23.25483.58.23.2551,022
13583.58.24.0/2283.58.24.1 to 83.58.27.25483.58.27.2551,022
13683.58.28.0/2283.58.28.1 to 83.58.31.25483.58.31.2551,022
13783.58.32.0/2283.58.32.1 to 83.58.35.25483.58.35.2551,022
13883.58.36.0/2283.58.36.1 to 83.58.39.25483.58.39.2551,022
13983.58.40.0/2283.58.40.1 to 83.58.43.25483.58.43.2551,022
14083.58.44.0/2283.58.44.1 to 83.58.47.25483.58.47.2551,022
14183.58.48.0/2283.58.48.1 to 83.58.51.25483.58.51.2551,022
14283.58.52.0/2283.58.52.1 to 83.58.55.25483.58.55.2551,022
14383.58.56.0/2283.58.56.1 to 83.58.59.25483.58.59.2551,022
14483.58.60.0/2283.58.60.1 to 83.58.63.25483.58.63.2551,022
14583.58.64.0/2283.58.64.1 to 83.58.67.25483.58.67.2551,022
14683.58.68.0/2283.58.68.1 to 83.58.71.25483.58.71.2551,022
14783.58.72.0/2283.58.72.1 to 83.58.75.25483.58.75.2551,022
14883.58.76.0/2283.58.76.1 to 83.58.79.25483.58.79.2551,022
14983.58.80.0/2283.58.80.1 to 83.58.83.25483.58.83.2551,022
15083.58.84.0/2283.58.84.1 to 83.58.87.25483.58.87.2551,022
15183.58.88.0/2283.58.88.1 to 83.58.91.25483.58.91.2551,022
15283.58.92.0/2283.58.92.1 to 83.58.95.25483.58.95.2551,022
15383.58.96.0/2283.58.96.1 to 83.58.99.25483.58.99.2551,022
15483.58.100.0/2283.58.100.1 to 83.58.103.25483.58.103.2551,022
15583.58.104.0/2283.58.104.1 to 83.58.107.25483.58.107.2551,022
15683.58.108.0/2283.58.108.1 to 83.58.111.25483.58.111.2551,022
15783.58.112.0/2283.58.112.1 to 83.58.115.25483.58.115.2551,022
15883.58.116.0/2283.58.116.1 to 83.58.119.25483.58.119.2551,022
15983.58.120.0/2283.58.120.1 to 83.58.123.25483.58.123.2551,022
16083.58.124.0/2283.58.124.1 to 83.58.127.25483.58.127.2551,022
16183.58.128.0/2283.58.128.1 to 83.58.131.25483.58.131.2551,022
16283.58.132.0/2283.58.132.1 to 83.58.135.25483.58.135.2551,022
16383.58.136.0/2283.58.136.1 to 83.58.139.25483.58.139.2551,022
16483.58.140.0/2283.58.140.1 to 83.58.143.25483.58.143.2551,022
16583.58.144.0/2283.58.144.1 to 83.58.147.25483.58.147.2551,022
16683.58.148.0/2283.58.148.1 to 83.58.151.25483.58.151.2551,022
16783.58.152.0/2283.58.152.1 to 83.58.155.25483.58.155.2551,022
16883.58.156.0/2283.58.156.1 to 83.58.159.25483.58.159.2551,022
16983.58.160.0/2283.58.160.1 to 83.58.163.25483.58.163.2551,022
17083.58.164.0/2283.58.164.1 to 83.58.167.25483.58.167.2551,022
17183.58.168.0/2283.58.168.1 to 83.58.171.25483.58.171.2551,022
17283.58.172.0/2283.58.172.1 to 83.58.175.25483.58.175.2551,022
17383.58.176.0/2283.58.176.1 to 83.58.179.25483.58.179.2551,022
17483.58.180.0/2283.58.180.1 to 83.58.183.25483.58.183.2551,022
17583.58.184.0/2283.58.184.1 to 83.58.187.25483.58.187.2551,022
17683.58.188.0/2283.58.188.1 to 83.58.191.25483.58.191.2551,022
17783.58.192.0/2283.58.192.1 to 83.58.195.25483.58.195.2551,022
17883.58.196.0/2283.58.196.1 to 83.58.199.25483.58.199.2551,022
17983.58.200.0/2283.58.200.1 to 83.58.203.25483.58.203.2551,022
18083.58.204.0/2283.58.204.1 to 83.58.207.25483.58.207.2551,022
18183.58.208.0/2283.58.208.1 to 83.58.211.25483.58.211.2551,022
18283.58.212.0/2283.58.212.1 to 83.58.215.25483.58.215.2551,022
18383.58.216.0/2283.58.216.1 to 83.58.219.25483.58.219.2551,022
18483.58.220.0/2283.58.220.1 to 83.58.223.25483.58.223.2551,022
18583.58.224.0/2283.58.224.1 to 83.58.227.25483.58.227.2551,022
18683.58.228.0/2283.58.228.1 to 83.58.231.25483.58.231.2551,022
18783.58.232.0/2283.58.232.1 to 83.58.235.25483.58.235.2551,022
18883.58.236.0/2283.58.236.1 to 83.58.239.25483.58.239.2551,022
18983.58.240.0/2283.58.240.1 to 83.58.243.25483.58.243.2551,022
19083.58.244.0/2283.58.244.1 to 83.58.247.25483.58.247.2551,022
19183.58.248.0/2283.58.248.1 to 83.58.251.25483.58.251.2551,022
19283.58.252.0/2283.58.252.1 to 83.58.255.25483.58.255.2551,022
19383.59.0.0/2283.59.0.1 to 83.59.3.25483.59.3.2551,022
19483.59.4.0/2283.59.4.1 to 83.59.7.25483.59.7.2551,022
19583.59.8.0/2283.59.8.1 to 83.59.11.25483.59.11.2551,022
19683.59.12.0/2283.59.12.1 to 83.59.15.25483.59.15.2551,022
19783.59.16.0/2283.59.16.1 to 83.59.19.25483.59.19.2551,022
19883.59.20.0/2283.59.20.1 to 83.59.23.25483.59.23.2551,022
19983.59.24.0/2283.59.24.1 to 83.59.27.25483.59.27.2551,022
20083.59.28.0/2283.59.28.1 to 83.59.31.25483.59.31.2551,022
20183.59.32.0/2283.59.32.1 to 83.59.35.25483.59.35.2551,022
20283.59.36.0/2283.59.36.1 to 83.59.39.25483.59.39.2551,022
20383.59.40.0/2283.59.40.1 to 83.59.43.25483.59.43.2551,022
20483.59.44.0/2283.59.44.1 to 83.59.47.25483.59.47.2551,022
20583.59.48.0/2283.59.48.1 to 83.59.51.25483.59.51.2551,022
20683.59.52.0/2283.59.52.1 to 83.59.55.25483.59.55.2551,022
20783.59.56.0/2283.59.56.1 to 83.59.59.25483.59.59.2551,022
20883.59.60.0/2283.59.60.1 to 83.59.63.25483.59.63.2551,022
20983.59.64.0/2283.59.64.1 to 83.59.67.25483.59.67.2551,022
21083.59.68.0/2283.59.68.1 to 83.59.71.25483.59.71.2551,022
21183.59.72.0/2283.59.72.1 to 83.59.75.25483.59.75.2551,022
21283.59.76.0/2283.59.76.1 to 83.59.79.25483.59.79.2551,022
21383.59.80.0/2283.59.80.1 to 83.59.83.25483.59.83.2551,022
21483.59.84.0/2283.59.84.1 to 83.59.87.25483.59.87.2551,022
21583.59.88.0/2283.59.88.1 to 83.59.91.25483.59.91.2551,022
21683.59.92.0/2283.59.92.1 to 83.59.95.25483.59.95.2551,022
21783.59.96.0/2283.59.96.1 to 83.59.99.25483.59.99.2551,022
21883.59.100.0/2283.59.100.1 to 83.59.103.25483.59.103.2551,022
21983.59.104.0/2283.59.104.1 to 83.59.107.25483.59.107.2551,022
22083.59.108.0/2283.59.108.1 to 83.59.111.25483.59.111.2551,022
22183.59.112.0/2283.59.112.1 to 83.59.115.25483.59.115.2551,022
22283.59.116.0/2283.59.116.1 to 83.59.119.25483.59.119.2551,022
22383.59.120.0/2283.59.120.1 to 83.59.123.25483.59.123.2551,022
22483.59.124.0/2283.59.124.1 to 83.59.127.25483.59.127.2551,022
22583.59.128.0/2283.59.128.1 to 83.59.131.25483.59.131.2551,022
22683.59.132.0/2283.59.132.1 to 83.59.135.25483.59.135.2551,022
22783.59.136.0/2283.59.136.1 to 83.59.139.25483.59.139.2551,022
22883.59.140.0/2283.59.140.1 to 83.59.143.25483.59.143.2551,022
22983.59.144.0/2283.59.144.1 to 83.59.147.25483.59.147.2551,022
23083.59.148.0/2283.59.148.1 to 83.59.151.25483.59.151.2551,022
23183.59.152.0/2283.59.152.1 to 83.59.155.25483.59.155.2551,022
23283.59.156.0/2283.59.156.1 to 83.59.159.25483.59.159.2551,022
23383.59.160.0/2283.59.160.1 to 83.59.163.25483.59.163.2551,022
23483.59.164.0/2283.59.164.1 to 83.59.167.25483.59.167.2551,022
23583.59.168.0/2283.59.168.1 to 83.59.171.25483.59.171.2551,022
23683.59.172.0/2283.59.172.1 to 83.59.175.25483.59.175.2551,022
23783.59.176.0/2283.59.176.1 to 83.59.179.25483.59.179.2551,022
23883.59.180.0/2283.59.180.1 to 83.59.183.25483.59.183.2551,022
23983.59.184.0/2283.59.184.1 to 83.59.187.25483.59.187.2551,022
24083.59.188.0/2283.59.188.1 to 83.59.191.25483.59.191.2551,022
24183.59.192.0/2283.59.192.1 to 83.59.195.25483.59.195.2551,022
24283.59.196.0/2283.59.196.1 to 83.59.199.25483.59.199.2551,022
24383.59.200.0/2283.59.200.1 to 83.59.203.25483.59.203.2551,022
24483.59.204.0/2283.59.204.1 to 83.59.207.25483.59.207.2551,022
24583.59.208.0/2283.59.208.1 to 83.59.211.25483.59.211.2551,022
24683.59.212.0/2283.59.212.1 to 83.59.215.25483.59.215.2551,022
24783.59.216.0/2283.59.216.1 to 83.59.219.25483.59.219.2551,022
24883.59.220.0/2283.59.220.1 to 83.59.223.25483.59.223.2551,022
24983.59.224.0/2283.59.224.1 to 83.59.227.25483.59.227.2551,022
25083.59.228.0/2283.59.228.1 to 83.59.231.25483.59.231.2551,022
25183.59.232.0/2283.59.232.1 to 83.59.235.25483.59.235.2551,022
25283.59.236.0/2283.59.236.1 to 83.59.239.25483.59.239.2551,022
25383.59.240.0/2283.59.240.1 to 83.59.243.25483.59.243.2551,022
25483.59.244.0/2283.59.244.1 to 83.59.247.25483.59.247.2551,022
25583.59.248.0/2283.59.248.1 to 83.59.251.25483.59.251.2551,022
25683.59.252.0/2283.59.252.1 to 83.59.255.25483.59.255.2551,022

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.