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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.

Network83.232.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
83.232.0.0
Broadcast address
83.239.255.255
First usable
83.232.0.1
Last usable
83.239.255.254
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 53E80000 · Integer 1407713280 to 1408237567
Reverse DNS zones
232.83.in-addr.arpa
233.83.in-addr.arpa
234.83.in-addr.arpa
235.83.in-addr.arpa
236.83.in-addr.arpa
237.83.in-addr.arpa
238.83.in-addr.arpa
239.83.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
Address01010011.11101000.00000000.0000000083.232.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network01010011.11101000.00000000.0000000083.232.0.0
Broadcast01010011.11101111.11111111.1111111183.239.255.255
Split into smaller subnets/25
/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)

83.232.0.0/13 makes 4,096 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
183.232.0.0/2583.232.0.1 to 83.232.0.12683.232.0.127126
283.232.0.128/2583.232.0.129 to 83.232.0.25483.232.0.255126
383.232.1.0/2583.232.1.1 to 83.232.1.12683.232.1.127126
483.232.1.128/2583.232.1.129 to 83.232.1.25483.232.1.255126
583.232.2.0/2583.232.2.1 to 83.232.2.12683.232.2.127126
683.232.2.128/2583.232.2.129 to 83.232.2.25483.232.2.255126
783.232.3.0/2583.232.3.1 to 83.232.3.12683.232.3.127126
883.232.3.128/2583.232.3.129 to 83.232.3.25483.232.3.255126
983.232.4.0/2583.232.4.1 to 83.232.4.12683.232.4.127126
1083.232.4.128/2583.232.4.129 to 83.232.4.25483.232.4.255126
1183.232.5.0/2583.232.5.1 to 83.232.5.12683.232.5.127126
1283.232.5.128/2583.232.5.129 to 83.232.5.25483.232.5.255126
1383.232.6.0/2583.232.6.1 to 83.232.6.12683.232.6.127126
1483.232.6.128/2583.232.6.129 to 83.232.6.25483.232.6.255126
1583.232.7.0/2583.232.7.1 to 83.232.7.12683.232.7.127126
1683.232.7.128/2583.232.7.129 to 83.232.7.25483.232.7.255126
1783.232.8.0/2583.232.8.1 to 83.232.8.12683.232.8.127126
1883.232.8.128/2583.232.8.129 to 83.232.8.25483.232.8.255126
1983.232.9.0/2583.232.9.1 to 83.232.9.12683.232.9.127126
2083.232.9.128/2583.232.9.129 to 83.232.9.25483.232.9.255126
2183.232.10.0/2583.232.10.1 to 83.232.10.12683.232.10.127126
2283.232.10.128/2583.232.10.129 to 83.232.10.25483.232.10.255126
2383.232.11.0/2583.232.11.1 to 83.232.11.12683.232.11.127126
2483.232.11.128/2583.232.11.129 to 83.232.11.25483.232.11.255126
2583.232.12.0/2583.232.12.1 to 83.232.12.12683.232.12.127126
2683.232.12.128/2583.232.12.129 to 83.232.12.25483.232.12.255126
2783.232.13.0/2583.232.13.1 to 83.232.13.12683.232.13.127126
2883.232.13.128/2583.232.13.129 to 83.232.13.25483.232.13.255126
2983.232.14.0/2583.232.14.1 to 83.232.14.12683.232.14.127126
3083.232.14.128/2583.232.14.129 to 83.232.14.25483.232.14.255126
3183.232.15.0/2583.232.15.1 to 83.232.15.12683.232.15.127126
3283.232.15.128/2583.232.15.129 to 83.232.15.25483.232.15.255126
3383.232.16.0/2583.232.16.1 to 83.232.16.12683.232.16.127126
3483.232.16.128/2583.232.16.129 to 83.232.16.25483.232.16.255126
3583.232.17.0/2583.232.17.1 to 83.232.17.12683.232.17.127126
3683.232.17.128/2583.232.17.129 to 83.232.17.25483.232.17.255126
3783.232.18.0/2583.232.18.1 to 83.232.18.12683.232.18.127126
3883.232.18.128/2583.232.18.129 to 83.232.18.25483.232.18.255126
3983.232.19.0/2583.232.19.1 to 83.232.19.12683.232.19.127126
4083.232.19.128/2583.232.19.129 to 83.232.19.25483.232.19.255126
4183.232.20.0/2583.232.20.1 to 83.232.20.12683.232.20.127126
4283.232.20.128/2583.232.20.129 to 83.232.20.25483.232.20.255126
4383.232.21.0/2583.232.21.1 to 83.232.21.12683.232.21.127126
4483.232.21.128/2583.232.21.129 to 83.232.21.25483.232.21.255126
4583.232.22.0/2583.232.22.1 to 83.232.22.12683.232.22.127126
4683.232.22.128/2583.232.22.129 to 83.232.22.25483.232.22.255126
4783.232.23.0/2583.232.23.1 to 83.232.23.12683.232.23.127126
4883.232.23.128/2583.232.23.129 to 83.232.23.25483.232.23.255126
4983.232.24.0/2583.232.24.1 to 83.232.24.12683.232.24.127126
5083.232.24.128/2583.232.24.129 to 83.232.24.25483.232.24.255126
5183.232.25.0/2583.232.25.1 to 83.232.25.12683.232.25.127126
5283.232.25.128/2583.232.25.129 to 83.232.25.25483.232.25.255126
5383.232.26.0/2583.232.26.1 to 83.232.26.12683.232.26.127126
5483.232.26.128/2583.232.26.129 to 83.232.26.25483.232.26.255126
5583.232.27.0/2583.232.27.1 to 83.232.27.12683.232.27.127126
5683.232.27.128/2583.232.27.129 to 83.232.27.25483.232.27.255126
5783.232.28.0/2583.232.28.1 to 83.232.28.12683.232.28.127126
5883.232.28.128/2583.232.28.129 to 83.232.28.25483.232.28.255126
5983.232.29.0/2583.232.29.1 to 83.232.29.12683.232.29.127126
6083.232.29.128/2583.232.29.129 to 83.232.29.25483.232.29.255126
6183.232.30.0/2583.232.30.1 to 83.232.30.12683.232.30.127126
6283.232.30.128/2583.232.30.129 to 83.232.30.25483.232.30.255126
6383.232.31.0/2583.232.31.1 to 83.232.31.12683.232.31.127126
6483.232.31.128/2583.232.31.129 to 83.232.31.25483.232.31.255126
6583.232.32.0/2583.232.32.1 to 83.232.32.12683.232.32.127126
6683.232.32.128/2583.232.32.129 to 83.232.32.25483.232.32.255126
6783.232.33.0/2583.232.33.1 to 83.232.33.12683.232.33.127126
6883.232.33.128/2583.232.33.129 to 83.232.33.25483.232.33.255126
6983.232.34.0/2583.232.34.1 to 83.232.34.12683.232.34.127126
7083.232.34.128/2583.232.34.129 to 83.232.34.25483.232.34.255126
7183.232.35.0/2583.232.35.1 to 83.232.35.12683.232.35.127126
7283.232.35.128/2583.232.35.129 to 83.232.35.25483.232.35.255126
7383.232.36.0/2583.232.36.1 to 83.232.36.12683.232.36.127126
7483.232.36.128/2583.232.36.129 to 83.232.36.25483.232.36.255126
7583.232.37.0/2583.232.37.1 to 83.232.37.12683.232.37.127126
7683.232.37.128/2583.232.37.129 to 83.232.37.25483.232.37.255126
7783.232.38.0/2583.232.38.1 to 83.232.38.12683.232.38.127126
7883.232.38.128/2583.232.38.129 to 83.232.38.25483.232.38.255126
7983.232.39.0/2583.232.39.1 to 83.232.39.12683.232.39.127126
8083.232.39.128/2583.232.39.129 to 83.232.39.25483.232.39.255126
8183.232.40.0/2583.232.40.1 to 83.232.40.12683.232.40.127126
8283.232.40.128/2583.232.40.129 to 83.232.40.25483.232.40.255126
8383.232.41.0/2583.232.41.1 to 83.232.41.12683.232.41.127126
8483.232.41.128/2583.232.41.129 to 83.232.41.25483.232.41.255126
8583.232.42.0/2583.232.42.1 to 83.232.42.12683.232.42.127126
8683.232.42.128/2583.232.42.129 to 83.232.42.25483.232.42.255126
8783.232.43.0/2583.232.43.1 to 83.232.43.12683.232.43.127126
8883.232.43.128/2583.232.43.129 to 83.232.43.25483.232.43.255126
8983.232.44.0/2583.232.44.1 to 83.232.44.12683.232.44.127126
9083.232.44.128/2583.232.44.129 to 83.232.44.25483.232.44.255126
9183.232.45.0/2583.232.45.1 to 83.232.45.12683.232.45.127126
9283.232.45.128/2583.232.45.129 to 83.232.45.25483.232.45.255126
9383.232.46.0/2583.232.46.1 to 83.232.46.12683.232.46.127126
9483.232.46.128/2583.232.46.129 to 83.232.46.25483.232.46.255126
9583.232.47.0/2583.232.47.1 to 83.232.47.12683.232.47.127126
9683.232.47.128/2583.232.47.129 to 83.232.47.25483.232.47.255126
9783.232.48.0/2583.232.48.1 to 83.232.48.12683.232.48.127126
9883.232.48.128/2583.232.48.129 to 83.232.48.25483.232.48.255126
9983.232.49.0/2583.232.49.1 to 83.232.49.12683.232.49.127126
10083.232.49.128/2583.232.49.129 to 83.232.49.25483.232.49.255126
10183.232.50.0/2583.232.50.1 to 83.232.50.12683.232.50.127126
10283.232.50.128/2583.232.50.129 to 83.232.50.25483.232.50.255126
10383.232.51.0/2583.232.51.1 to 83.232.51.12683.232.51.127126
10483.232.51.128/2583.232.51.129 to 83.232.51.25483.232.51.255126
10583.232.52.0/2583.232.52.1 to 83.232.52.12683.232.52.127126
10683.232.52.128/2583.232.52.129 to 83.232.52.25483.232.52.255126
10783.232.53.0/2583.232.53.1 to 83.232.53.12683.232.53.127126
10883.232.53.128/2583.232.53.129 to 83.232.53.25483.232.53.255126
10983.232.54.0/2583.232.54.1 to 83.232.54.12683.232.54.127126
11083.232.54.128/2583.232.54.129 to 83.232.54.25483.232.54.255126
11183.232.55.0/2583.232.55.1 to 83.232.55.12683.232.55.127126
11283.232.55.128/2583.232.55.129 to 83.232.55.25483.232.55.255126
11383.232.56.0/2583.232.56.1 to 83.232.56.12683.232.56.127126
11483.232.56.128/2583.232.56.129 to 83.232.56.25483.232.56.255126
11583.232.57.0/2583.232.57.1 to 83.232.57.12683.232.57.127126
11683.232.57.128/2583.232.57.129 to 83.232.57.25483.232.57.255126
11783.232.58.0/2583.232.58.1 to 83.232.58.12683.232.58.127126
11883.232.58.128/2583.232.58.129 to 83.232.58.25483.232.58.255126
11983.232.59.0/2583.232.59.1 to 83.232.59.12683.232.59.127126
12083.232.59.128/2583.232.59.129 to 83.232.59.25483.232.59.255126
12183.232.60.0/2583.232.60.1 to 83.232.60.12683.232.60.127126
12283.232.60.128/2583.232.60.129 to 83.232.60.25483.232.60.255126
12383.232.61.0/2583.232.61.1 to 83.232.61.12683.232.61.127126
12483.232.61.128/2583.232.61.129 to 83.232.61.25483.232.61.255126
12583.232.62.0/2583.232.62.1 to 83.232.62.12683.232.62.127126
12683.232.62.128/2583.232.62.129 to 83.232.62.25483.232.62.255126
12783.232.63.0/2583.232.63.1 to 83.232.63.12683.232.63.127126
12883.232.63.128/2583.232.63.129 to 83.232.63.25483.232.63.255126
12983.232.64.0/2583.232.64.1 to 83.232.64.12683.232.64.127126
13083.232.64.128/2583.232.64.129 to 83.232.64.25483.232.64.255126
13183.232.65.0/2583.232.65.1 to 83.232.65.12683.232.65.127126
13283.232.65.128/2583.232.65.129 to 83.232.65.25483.232.65.255126
13383.232.66.0/2583.232.66.1 to 83.232.66.12683.232.66.127126
13483.232.66.128/2583.232.66.129 to 83.232.66.25483.232.66.255126
13583.232.67.0/2583.232.67.1 to 83.232.67.12683.232.67.127126
13683.232.67.128/2583.232.67.129 to 83.232.67.25483.232.67.255126
13783.232.68.0/2583.232.68.1 to 83.232.68.12683.232.68.127126
13883.232.68.128/2583.232.68.129 to 83.232.68.25483.232.68.255126
13983.232.69.0/2583.232.69.1 to 83.232.69.12683.232.69.127126
14083.232.69.128/2583.232.69.129 to 83.232.69.25483.232.69.255126
14183.232.70.0/2583.232.70.1 to 83.232.70.12683.232.70.127126
14283.232.70.128/2583.232.70.129 to 83.232.70.25483.232.70.255126
14383.232.71.0/2583.232.71.1 to 83.232.71.12683.232.71.127126
14483.232.71.128/2583.232.71.129 to 83.232.71.25483.232.71.255126
14583.232.72.0/2583.232.72.1 to 83.232.72.12683.232.72.127126
14683.232.72.128/2583.232.72.129 to 83.232.72.25483.232.72.255126
14783.232.73.0/2583.232.73.1 to 83.232.73.12683.232.73.127126
14883.232.73.128/2583.232.73.129 to 83.232.73.25483.232.73.255126
14983.232.74.0/2583.232.74.1 to 83.232.74.12683.232.74.127126
15083.232.74.128/2583.232.74.129 to 83.232.74.25483.232.74.255126
15183.232.75.0/2583.232.75.1 to 83.232.75.12683.232.75.127126
15283.232.75.128/2583.232.75.129 to 83.232.75.25483.232.75.255126
15383.232.76.0/2583.232.76.1 to 83.232.76.12683.232.76.127126
15483.232.76.128/2583.232.76.129 to 83.232.76.25483.232.76.255126
15583.232.77.0/2583.232.77.1 to 83.232.77.12683.232.77.127126
15683.232.77.128/2583.232.77.129 to 83.232.77.25483.232.77.255126
15783.232.78.0/2583.232.78.1 to 83.232.78.12683.232.78.127126
15883.232.78.128/2583.232.78.129 to 83.232.78.25483.232.78.255126
15983.232.79.0/2583.232.79.1 to 83.232.79.12683.232.79.127126
16083.232.79.128/2583.232.79.129 to 83.232.79.25483.232.79.255126
16183.232.80.0/2583.232.80.1 to 83.232.80.12683.232.80.127126
16283.232.80.128/2583.232.80.129 to 83.232.80.25483.232.80.255126
16383.232.81.0/2583.232.81.1 to 83.232.81.12683.232.81.127126
16483.232.81.128/2583.232.81.129 to 83.232.81.25483.232.81.255126
16583.232.82.0/2583.232.82.1 to 83.232.82.12683.232.82.127126
16683.232.82.128/2583.232.82.129 to 83.232.82.25483.232.82.255126
16783.232.83.0/2583.232.83.1 to 83.232.83.12683.232.83.127126
16883.232.83.128/2583.232.83.129 to 83.232.83.25483.232.83.255126
16983.232.84.0/2583.232.84.1 to 83.232.84.12683.232.84.127126
17083.232.84.128/2583.232.84.129 to 83.232.84.25483.232.84.255126
17183.232.85.0/2583.232.85.1 to 83.232.85.12683.232.85.127126
17283.232.85.128/2583.232.85.129 to 83.232.85.25483.232.85.255126
17383.232.86.0/2583.232.86.1 to 83.232.86.12683.232.86.127126
17483.232.86.128/2583.232.86.129 to 83.232.86.25483.232.86.255126
17583.232.87.0/2583.232.87.1 to 83.232.87.12683.232.87.127126
17683.232.87.128/2583.232.87.129 to 83.232.87.25483.232.87.255126
17783.232.88.0/2583.232.88.1 to 83.232.88.12683.232.88.127126
17883.232.88.128/2583.232.88.129 to 83.232.88.25483.232.88.255126
17983.232.89.0/2583.232.89.1 to 83.232.89.12683.232.89.127126
18083.232.89.128/2583.232.89.129 to 83.232.89.25483.232.89.255126
18183.232.90.0/2583.232.90.1 to 83.232.90.12683.232.90.127126
18283.232.90.128/2583.232.90.129 to 83.232.90.25483.232.90.255126
18383.232.91.0/2583.232.91.1 to 83.232.91.12683.232.91.127126
18483.232.91.128/2583.232.91.129 to 83.232.91.25483.232.91.255126
18583.232.92.0/2583.232.92.1 to 83.232.92.12683.232.92.127126
18683.232.92.128/2583.232.92.129 to 83.232.92.25483.232.92.255126
18783.232.93.0/2583.232.93.1 to 83.232.93.12683.232.93.127126
18883.232.93.128/2583.232.93.129 to 83.232.93.25483.232.93.255126
18983.232.94.0/2583.232.94.1 to 83.232.94.12683.232.94.127126
19083.232.94.128/2583.232.94.129 to 83.232.94.25483.232.94.255126
19183.232.95.0/2583.232.95.1 to 83.232.95.12683.232.95.127126
19283.232.95.128/2583.232.95.129 to 83.232.95.25483.232.95.255126
19383.232.96.0/2583.232.96.1 to 83.232.96.12683.232.96.127126
19483.232.96.128/2583.232.96.129 to 83.232.96.25483.232.96.255126
19583.232.97.0/2583.232.97.1 to 83.232.97.12683.232.97.127126
19683.232.97.128/2583.232.97.129 to 83.232.97.25483.232.97.255126
19783.232.98.0/2583.232.98.1 to 83.232.98.12683.232.98.127126
19883.232.98.128/2583.232.98.129 to 83.232.98.25483.232.98.255126
19983.232.99.0/2583.232.99.1 to 83.232.99.12683.232.99.127126
20083.232.99.128/2583.232.99.129 to 83.232.99.25483.232.99.255126
20183.232.100.0/2583.232.100.1 to 83.232.100.12683.232.100.127126
20283.232.100.128/2583.232.100.129 to 83.232.100.25483.232.100.255126
20383.232.101.0/2583.232.101.1 to 83.232.101.12683.232.101.127126
20483.232.101.128/2583.232.101.129 to 83.232.101.25483.232.101.255126
20583.232.102.0/2583.232.102.1 to 83.232.102.12683.232.102.127126
20683.232.102.128/2583.232.102.129 to 83.232.102.25483.232.102.255126
20783.232.103.0/2583.232.103.1 to 83.232.103.12683.232.103.127126
20883.232.103.128/2583.232.103.129 to 83.232.103.25483.232.103.255126
20983.232.104.0/2583.232.104.1 to 83.232.104.12683.232.104.127126
21083.232.104.128/2583.232.104.129 to 83.232.104.25483.232.104.255126
21183.232.105.0/2583.232.105.1 to 83.232.105.12683.232.105.127126
21283.232.105.128/2583.232.105.129 to 83.232.105.25483.232.105.255126
21383.232.106.0/2583.232.106.1 to 83.232.106.12683.232.106.127126
21483.232.106.128/2583.232.106.129 to 83.232.106.25483.232.106.255126
21583.232.107.0/2583.232.107.1 to 83.232.107.12683.232.107.127126
21683.232.107.128/2583.232.107.129 to 83.232.107.25483.232.107.255126
21783.232.108.0/2583.232.108.1 to 83.232.108.12683.232.108.127126
21883.232.108.128/2583.232.108.129 to 83.232.108.25483.232.108.255126
21983.232.109.0/2583.232.109.1 to 83.232.109.12683.232.109.127126
22083.232.109.128/2583.232.109.129 to 83.232.109.25483.232.109.255126
22183.232.110.0/2583.232.110.1 to 83.232.110.12683.232.110.127126
22283.232.110.128/2583.232.110.129 to 83.232.110.25483.232.110.255126
22383.232.111.0/2583.232.111.1 to 83.232.111.12683.232.111.127126
22483.232.111.128/2583.232.111.129 to 83.232.111.25483.232.111.255126
22583.232.112.0/2583.232.112.1 to 83.232.112.12683.232.112.127126
22683.232.112.128/2583.232.112.129 to 83.232.112.25483.232.112.255126
22783.232.113.0/2583.232.113.1 to 83.232.113.12683.232.113.127126
22883.232.113.128/2583.232.113.129 to 83.232.113.25483.232.113.255126
22983.232.114.0/2583.232.114.1 to 83.232.114.12683.232.114.127126
23083.232.114.128/2583.232.114.129 to 83.232.114.25483.232.114.255126
23183.232.115.0/2583.232.115.1 to 83.232.115.12683.232.115.127126
23283.232.115.128/2583.232.115.129 to 83.232.115.25483.232.115.255126
23383.232.116.0/2583.232.116.1 to 83.232.116.12683.232.116.127126
23483.232.116.128/2583.232.116.129 to 83.232.116.25483.232.116.255126
23583.232.117.0/2583.232.117.1 to 83.232.117.12683.232.117.127126
23683.232.117.128/2583.232.117.129 to 83.232.117.25483.232.117.255126
23783.232.118.0/2583.232.118.1 to 83.232.118.12683.232.118.127126
23883.232.118.128/2583.232.118.129 to 83.232.118.25483.232.118.255126
23983.232.119.0/2583.232.119.1 to 83.232.119.12683.232.119.127126
24083.232.119.128/2583.232.119.129 to 83.232.119.25483.232.119.255126
24183.232.120.0/2583.232.120.1 to 83.232.120.12683.232.120.127126
24283.232.120.128/2583.232.120.129 to 83.232.120.25483.232.120.255126
24383.232.121.0/2583.232.121.1 to 83.232.121.12683.232.121.127126
24483.232.121.128/2583.232.121.129 to 83.232.121.25483.232.121.255126
24583.232.122.0/2583.232.122.1 to 83.232.122.12683.232.122.127126
24683.232.122.128/2583.232.122.129 to 83.232.122.25483.232.122.255126
24783.232.123.0/2583.232.123.1 to 83.232.123.12683.232.123.127126
24883.232.123.128/2583.232.123.129 to 83.232.123.25483.232.123.255126
24983.232.124.0/2583.232.124.1 to 83.232.124.12683.232.124.127126
25083.232.124.128/2583.232.124.129 to 83.232.124.25483.232.124.255126
25183.232.125.0/2583.232.125.1 to 83.232.125.12683.232.125.127126
25283.232.125.128/2583.232.125.129 to 83.232.125.25483.232.125.255126
25383.232.126.0/2583.232.126.1 to 83.232.126.12683.232.126.127126
25483.232.126.128/2583.232.126.129 to 83.232.126.25483.232.126.255126
25583.232.127.0/2583.232.127.1 to 83.232.127.12683.232.127.127126
25683.232.127.128/2583.232.127.129 to 83.232.127.25483.232.127.255126

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.