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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.

Network83.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
83.0.0.0
Broadcast address
83.127.255.255
First usable
83.0.0.1
Last usable
83.127.255.254
Usable hosts
8,388,606 (8,388,608 less the network and broadcast addresses)
Subnet mask
255.128.0.0
Wildcard mask
0.127.255.255 (Cisco ACLs, OSPF)
Prefix length
/9
Type
Public public
Old class
A (default /8)
As numbers
Hex 53000000 · Integer 1392508928 to 1400897535
Reverse DNS zones
0.83.in-addr.arpa
1.83.in-addr.arpa
2.83.in-addr.arpa
3.83.in-addr.arpa
4.83.in-addr.arpa
5.83.in-addr.arpa
6.83.in-addr.arpa
7.83.in-addr.arpa
8.83.in-addr.arpa
9.83.in-addr.arpa
10.83.in-addr.arpa
11.83.in-addr.arpa
12.83.in-addr.arpa
13.83.in-addr.arpa
14.83.in-addr.arpa
15.83.in-addr.arpa
and 112 more
/9 is not on a 8-bit boundary, so it takes 128 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010011.00000000.00000000.0000000083.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network01010011.00000000.00000000.0000000083.0.0.0
Broadcast01010011.01111111.11111111.1111111183.127.255.255
Split into smaller subnets/17

83.0.0.0/9 makes 256 subnets of /17.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
183.0.0.0/1783.0.0.1 to 83.0.127.25483.0.127.25532,766
283.0.128.0/1783.0.128.1 to 83.0.255.25483.0.255.25532,766
383.1.0.0/1783.1.0.1 to 83.1.127.25483.1.127.25532,766
483.1.128.0/1783.1.128.1 to 83.1.255.25483.1.255.25532,766
583.2.0.0/1783.2.0.1 to 83.2.127.25483.2.127.25532,766
683.2.128.0/1783.2.128.1 to 83.2.255.25483.2.255.25532,766
783.3.0.0/1783.3.0.1 to 83.3.127.25483.3.127.25532,766
883.3.128.0/1783.3.128.1 to 83.3.255.25483.3.255.25532,766
983.4.0.0/1783.4.0.1 to 83.4.127.25483.4.127.25532,766
1083.4.128.0/1783.4.128.1 to 83.4.255.25483.4.255.25532,766
1183.5.0.0/1783.5.0.1 to 83.5.127.25483.5.127.25532,766
1283.5.128.0/1783.5.128.1 to 83.5.255.25483.5.255.25532,766
1383.6.0.0/1783.6.0.1 to 83.6.127.25483.6.127.25532,766
1483.6.128.0/1783.6.128.1 to 83.6.255.25483.6.255.25532,766
1583.7.0.0/1783.7.0.1 to 83.7.127.25483.7.127.25532,766
1683.7.128.0/1783.7.128.1 to 83.7.255.25483.7.255.25532,766
1783.8.0.0/1783.8.0.1 to 83.8.127.25483.8.127.25532,766
1883.8.128.0/1783.8.128.1 to 83.8.255.25483.8.255.25532,766
1983.9.0.0/1783.9.0.1 to 83.9.127.25483.9.127.25532,766
2083.9.128.0/1783.9.128.1 to 83.9.255.25483.9.255.25532,766
2183.10.0.0/1783.10.0.1 to 83.10.127.25483.10.127.25532,766
2283.10.128.0/1783.10.128.1 to 83.10.255.25483.10.255.25532,766
2383.11.0.0/1783.11.0.1 to 83.11.127.25483.11.127.25532,766
2483.11.128.0/1783.11.128.1 to 83.11.255.25483.11.255.25532,766
2583.12.0.0/1783.12.0.1 to 83.12.127.25483.12.127.25532,766
2683.12.128.0/1783.12.128.1 to 83.12.255.25483.12.255.25532,766
2783.13.0.0/1783.13.0.1 to 83.13.127.25483.13.127.25532,766
2883.13.128.0/1783.13.128.1 to 83.13.255.25483.13.255.25532,766
2983.14.0.0/1783.14.0.1 to 83.14.127.25483.14.127.25532,766
3083.14.128.0/1783.14.128.1 to 83.14.255.25483.14.255.25532,766
3183.15.0.0/1783.15.0.1 to 83.15.127.25483.15.127.25532,766
3283.15.128.0/1783.15.128.1 to 83.15.255.25483.15.255.25532,766
3383.16.0.0/1783.16.0.1 to 83.16.127.25483.16.127.25532,766
3483.16.128.0/1783.16.128.1 to 83.16.255.25483.16.255.25532,766
3583.17.0.0/1783.17.0.1 to 83.17.127.25483.17.127.25532,766
3683.17.128.0/1783.17.128.1 to 83.17.255.25483.17.255.25532,766
3783.18.0.0/1783.18.0.1 to 83.18.127.25483.18.127.25532,766
3883.18.128.0/1783.18.128.1 to 83.18.255.25483.18.255.25532,766
3983.19.0.0/1783.19.0.1 to 83.19.127.25483.19.127.25532,766
4083.19.128.0/1783.19.128.1 to 83.19.255.25483.19.255.25532,766
4183.20.0.0/1783.20.0.1 to 83.20.127.25483.20.127.25532,766
4283.20.128.0/1783.20.128.1 to 83.20.255.25483.20.255.25532,766
4383.21.0.0/1783.21.0.1 to 83.21.127.25483.21.127.25532,766
4483.21.128.0/1783.21.128.1 to 83.21.255.25483.21.255.25532,766
4583.22.0.0/1783.22.0.1 to 83.22.127.25483.22.127.25532,766
4683.22.128.0/1783.22.128.1 to 83.22.255.25483.22.255.25532,766
4783.23.0.0/1783.23.0.1 to 83.23.127.25483.23.127.25532,766
4883.23.128.0/1783.23.128.1 to 83.23.255.25483.23.255.25532,766
4983.24.0.0/1783.24.0.1 to 83.24.127.25483.24.127.25532,766
5083.24.128.0/1783.24.128.1 to 83.24.255.25483.24.255.25532,766
5183.25.0.0/1783.25.0.1 to 83.25.127.25483.25.127.25532,766
5283.25.128.0/1783.25.128.1 to 83.25.255.25483.25.255.25532,766
5383.26.0.0/1783.26.0.1 to 83.26.127.25483.26.127.25532,766
5483.26.128.0/1783.26.128.1 to 83.26.255.25483.26.255.25532,766
5583.27.0.0/1783.27.0.1 to 83.27.127.25483.27.127.25532,766
5683.27.128.0/1783.27.128.1 to 83.27.255.25483.27.255.25532,766
5783.28.0.0/1783.28.0.1 to 83.28.127.25483.28.127.25532,766
5883.28.128.0/1783.28.128.1 to 83.28.255.25483.28.255.25532,766
5983.29.0.0/1783.29.0.1 to 83.29.127.25483.29.127.25532,766
6083.29.128.0/1783.29.128.1 to 83.29.255.25483.29.255.25532,766
6183.30.0.0/1783.30.0.1 to 83.30.127.25483.30.127.25532,766
6283.30.128.0/1783.30.128.1 to 83.30.255.25483.30.255.25532,766
6383.31.0.0/1783.31.0.1 to 83.31.127.25483.31.127.25532,766
6483.31.128.0/1783.31.128.1 to 83.31.255.25483.31.255.25532,766
6583.32.0.0/1783.32.0.1 to 83.32.127.25483.32.127.25532,766
6683.32.128.0/1783.32.128.1 to 83.32.255.25483.32.255.25532,766
6783.33.0.0/1783.33.0.1 to 83.33.127.25483.33.127.25532,766
6883.33.128.0/1783.33.128.1 to 83.33.255.25483.33.255.25532,766
6983.34.0.0/1783.34.0.1 to 83.34.127.25483.34.127.25532,766
7083.34.128.0/1783.34.128.1 to 83.34.255.25483.34.255.25532,766
7183.35.0.0/1783.35.0.1 to 83.35.127.25483.35.127.25532,766
7283.35.128.0/1783.35.128.1 to 83.35.255.25483.35.255.25532,766
7383.36.0.0/1783.36.0.1 to 83.36.127.25483.36.127.25532,766
7483.36.128.0/1783.36.128.1 to 83.36.255.25483.36.255.25532,766
7583.37.0.0/1783.37.0.1 to 83.37.127.25483.37.127.25532,766
7683.37.128.0/1783.37.128.1 to 83.37.255.25483.37.255.25532,766
7783.38.0.0/1783.38.0.1 to 83.38.127.25483.38.127.25532,766
7883.38.128.0/1783.38.128.1 to 83.38.255.25483.38.255.25532,766
7983.39.0.0/1783.39.0.1 to 83.39.127.25483.39.127.25532,766
8083.39.128.0/1783.39.128.1 to 83.39.255.25483.39.255.25532,766
8183.40.0.0/1783.40.0.1 to 83.40.127.25483.40.127.25532,766
8283.40.128.0/1783.40.128.1 to 83.40.255.25483.40.255.25532,766
8383.41.0.0/1783.41.0.1 to 83.41.127.25483.41.127.25532,766
8483.41.128.0/1783.41.128.1 to 83.41.255.25483.41.255.25532,766
8583.42.0.0/1783.42.0.1 to 83.42.127.25483.42.127.25532,766
8683.42.128.0/1783.42.128.1 to 83.42.255.25483.42.255.25532,766
8783.43.0.0/1783.43.0.1 to 83.43.127.25483.43.127.25532,766
8883.43.128.0/1783.43.128.1 to 83.43.255.25483.43.255.25532,766
8983.44.0.0/1783.44.0.1 to 83.44.127.25483.44.127.25532,766
9083.44.128.0/1783.44.128.1 to 83.44.255.25483.44.255.25532,766
9183.45.0.0/1783.45.0.1 to 83.45.127.25483.45.127.25532,766
9283.45.128.0/1783.45.128.1 to 83.45.255.25483.45.255.25532,766
9383.46.0.0/1783.46.0.1 to 83.46.127.25483.46.127.25532,766
9483.46.128.0/1783.46.128.1 to 83.46.255.25483.46.255.25532,766
9583.47.0.0/1783.47.0.1 to 83.47.127.25483.47.127.25532,766
9683.47.128.0/1783.47.128.1 to 83.47.255.25483.47.255.25532,766
9783.48.0.0/1783.48.0.1 to 83.48.127.25483.48.127.25532,766
9883.48.128.0/1783.48.128.1 to 83.48.255.25483.48.255.25532,766
9983.49.0.0/1783.49.0.1 to 83.49.127.25483.49.127.25532,766
10083.49.128.0/1783.49.128.1 to 83.49.255.25483.49.255.25532,766
10183.50.0.0/1783.50.0.1 to 83.50.127.25483.50.127.25532,766
10283.50.128.0/1783.50.128.1 to 83.50.255.25483.50.255.25532,766
10383.51.0.0/1783.51.0.1 to 83.51.127.25483.51.127.25532,766
10483.51.128.0/1783.51.128.1 to 83.51.255.25483.51.255.25532,766
10583.52.0.0/1783.52.0.1 to 83.52.127.25483.52.127.25532,766
10683.52.128.0/1783.52.128.1 to 83.52.255.25483.52.255.25532,766
10783.53.0.0/1783.53.0.1 to 83.53.127.25483.53.127.25532,766
10883.53.128.0/1783.53.128.1 to 83.53.255.25483.53.255.25532,766
10983.54.0.0/1783.54.0.1 to 83.54.127.25483.54.127.25532,766
11083.54.128.0/1783.54.128.1 to 83.54.255.25483.54.255.25532,766
11183.55.0.0/1783.55.0.1 to 83.55.127.25483.55.127.25532,766
11283.55.128.0/1783.55.128.1 to 83.55.255.25483.55.255.25532,766
11383.56.0.0/1783.56.0.1 to 83.56.127.25483.56.127.25532,766
11483.56.128.0/1783.56.128.1 to 83.56.255.25483.56.255.25532,766
11583.57.0.0/1783.57.0.1 to 83.57.127.25483.57.127.25532,766
11683.57.128.0/1783.57.128.1 to 83.57.255.25483.57.255.25532,766
11783.58.0.0/1783.58.0.1 to 83.58.127.25483.58.127.25532,766
11883.58.128.0/1783.58.128.1 to 83.58.255.25483.58.255.25532,766
11983.59.0.0/1783.59.0.1 to 83.59.127.25483.59.127.25532,766
12083.59.128.0/1783.59.128.1 to 83.59.255.25483.59.255.25532,766
12183.60.0.0/1783.60.0.1 to 83.60.127.25483.60.127.25532,766
12283.60.128.0/1783.60.128.1 to 83.60.255.25483.60.255.25532,766
12383.61.0.0/1783.61.0.1 to 83.61.127.25483.61.127.25532,766
12483.61.128.0/1783.61.128.1 to 83.61.255.25483.61.255.25532,766
12583.62.0.0/1783.62.0.1 to 83.62.127.25483.62.127.25532,766
12683.62.128.0/1783.62.128.1 to 83.62.255.25483.62.255.25532,766
12783.63.0.0/1783.63.0.1 to 83.63.127.25483.63.127.25532,766
12883.63.128.0/1783.63.128.1 to 83.63.255.25483.63.255.25532,766
12983.64.0.0/1783.64.0.1 to 83.64.127.25483.64.127.25532,766
13083.64.128.0/1783.64.128.1 to 83.64.255.25483.64.255.25532,766
13183.65.0.0/1783.65.0.1 to 83.65.127.25483.65.127.25532,766
13283.65.128.0/1783.65.128.1 to 83.65.255.25483.65.255.25532,766
13383.66.0.0/1783.66.0.1 to 83.66.127.25483.66.127.25532,766
13483.66.128.0/1783.66.128.1 to 83.66.255.25483.66.255.25532,766
13583.67.0.0/1783.67.0.1 to 83.67.127.25483.67.127.25532,766
13683.67.128.0/1783.67.128.1 to 83.67.255.25483.67.255.25532,766
13783.68.0.0/1783.68.0.1 to 83.68.127.25483.68.127.25532,766
13883.68.128.0/1783.68.128.1 to 83.68.255.25483.68.255.25532,766
13983.69.0.0/1783.69.0.1 to 83.69.127.25483.69.127.25532,766
14083.69.128.0/1783.69.128.1 to 83.69.255.25483.69.255.25532,766
14183.70.0.0/1783.70.0.1 to 83.70.127.25483.70.127.25532,766
14283.70.128.0/1783.70.128.1 to 83.70.255.25483.70.255.25532,766
14383.71.0.0/1783.71.0.1 to 83.71.127.25483.71.127.25532,766
14483.71.128.0/1783.71.128.1 to 83.71.255.25483.71.255.25532,766
14583.72.0.0/1783.72.0.1 to 83.72.127.25483.72.127.25532,766
14683.72.128.0/1783.72.128.1 to 83.72.255.25483.72.255.25532,766
14783.73.0.0/1783.73.0.1 to 83.73.127.25483.73.127.25532,766
14883.73.128.0/1783.73.128.1 to 83.73.255.25483.73.255.25532,766
14983.74.0.0/1783.74.0.1 to 83.74.127.25483.74.127.25532,766
15083.74.128.0/1783.74.128.1 to 83.74.255.25483.74.255.25532,766
15183.75.0.0/1783.75.0.1 to 83.75.127.25483.75.127.25532,766
15283.75.128.0/1783.75.128.1 to 83.75.255.25483.75.255.25532,766
15383.76.0.0/1783.76.0.1 to 83.76.127.25483.76.127.25532,766
15483.76.128.0/1783.76.128.1 to 83.76.255.25483.76.255.25532,766
15583.77.0.0/1783.77.0.1 to 83.77.127.25483.77.127.25532,766
15683.77.128.0/1783.77.128.1 to 83.77.255.25483.77.255.25532,766
15783.78.0.0/1783.78.0.1 to 83.78.127.25483.78.127.25532,766
15883.78.128.0/1783.78.128.1 to 83.78.255.25483.78.255.25532,766
15983.79.0.0/1783.79.0.1 to 83.79.127.25483.79.127.25532,766
16083.79.128.0/1783.79.128.1 to 83.79.255.25483.79.255.25532,766
16183.80.0.0/1783.80.0.1 to 83.80.127.25483.80.127.25532,766
16283.80.128.0/1783.80.128.1 to 83.80.255.25483.80.255.25532,766
16383.81.0.0/1783.81.0.1 to 83.81.127.25483.81.127.25532,766
16483.81.128.0/1783.81.128.1 to 83.81.255.25483.81.255.25532,766
16583.82.0.0/1783.82.0.1 to 83.82.127.25483.82.127.25532,766
16683.82.128.0/1783.82.128.1 to 83.82.255.25483.82.255.25532,766
16783.83.0.0/1783.83.0.1 to 83.83.127.25483.83.127.25532,766
16883.83.128.0/1783.83.128.1 to 83.83.255.25483.83.255.25532,766
16983.84.0.0/1783.84.0.1 to 83.84.127.25483.84.127.25532,766
17083.84.128.0/1783.84.128.1 to 83.84.255.25483.84.255.25532,766
17183.85.0.0/1783.85.0.1 to 83.85.127.25483.85.127.25532,766
17283.85.128.0/1783.85.128.1 to 83.85.255.25483.85.255.25532,766
17383.86.0.0/1783.86.0.1 to 83.86.127.25483.86.127.25532,766
17483.86.128.0/1783.86.128.1 to 83.86.255.25483.86.255.25532,766
17583.87.0.0/1783.87.0.1 to 83.87.127.25483.87.127.25532,766
17683.87.128.0/1783.87.128.1 to 83.87.255.25483.87.255.25532,766
17783.88.0.0/1783.88.0.1 to 83.88.127.25483.88.127.25532,766
17883.88.128.0/1783.88.128.1 to 83.88.255.25483.88.255.25532,766
17983.89.0.0/1783.89.0.1 to 83.89.127.25483.89.127.25532,766
18083.89.128.0/1783.89.128.1 to 83.89.255.25483.89.255.25532,766
18183.90.0.0/1783.90.0.1 to 83.90.127.25483.90.127.25532,766
18283.90.128.0/1783.90.128.1 to 83.90.255.25483.90.255.25532,766
18383.91.0.0/1783.91.0.1 to 83.91.127.25483.91.127.25532,766
18483.91.128.0/1783.91.128.1 to 83.91.255.25483.91.255.25532,766
18583.92.0.0/1783.92.0.1 to 83.92.127.25483.92.127.25532,766
18683.92.128.0/1783.92.128.1 to 83.92.255.25483.92.255.25532,766
18783.93.0.0/1783.93.0.1 to 83.93.127.25483.93.127.25532,766
18883.93.128.0/1783.93.128.1 to 83.93.255.25483.93.255.25532,766
18983.94.0.0/1783.94.0.1 to 83.94.127.25483.94.127.25532,766
19083.94.128.0/1783.94.128.1 to 83.94.255.25483.94.255.25532,766
19183.95.0.0/1783.95.0.1 to 83.95.127.25483.95.127.25532,766
19283.95.128.0/1783.95.128.1 to 83.95.255.25483.95.255.25532,766
19383.96.0.0/1783.96.0.1 to 83.96.127.25483.96.127.25532,766
19483.96.128.0/1783.96.128.1 to 83.96.255.25483.96.255.25532,766
19583.97.0.0/1783.97.0.1 to 83.97.127.25483.97.127.25532,766
19683.97.128.0/1783.97.128.1 to 83.97.255.25483.97.255.25532,766
19783.98.0.0/1783.98.0.1 to 83.98.127.25483.98.127.25532,766
19883.98.128.0/1783.98.128.1 to 83.98.255.25483.98.255.25532,766
19983.99.0.0/1783.99.0.1 to 83.99.127.25483.99.127.25532,766
20083.99.128.0/1783.99.128.1 to 83.99.255.25483.99.255.25532,766
20183.100.0.0/1783.100.0.1 to 83.100.127.25483.100.127.25532,766
20283.100.128.0/1783.100.128.1 to 83.100.255.25483.100.255.25532,766
20383.101.0.0/1783.101.0.1 to 83.101.127.25483.101.127.25532,766
20483.101.128.0/1783.101.128.1 to 83.101.255.25483.101.255.25532,766
20583.102.0.0/1783.102.0.1 to 83.102.127.25483.102.127.25532,766
20683.102.128.0/1783.102.128.1 to 83.102.255.25483.102.255.25532,766
20783.103.0.0/1783.103.0.1 to 83.103.127.25483.103.127.25532,766
20883.103.128.0/1783.103.128.1 to 83.103.255.25483.103.255.25532,766
20983.104.0.0/1783.104.0.1 to 83.104.127.25483.104.127.25532,766
21083.104.128.0/1783.104.128.1 to 83.104.255.25483.104.255.25532,766
21183.105.0.0/1783.105.0.1 to 83.105.127.25483.105.127.25532,766
21283.105.128.0/1783.105.128.1 to 83.105.255.25483.105.255.25532,766
21383.106.0.0/1783.106.0.1 to 83.106.127.25483.106.127.25532,766
21483.106.128.0/1783.106.128.1 to 83.106.255.25483.106.255.25532,766
21583.107.0.0/1783.107.0.1 to 83.107.127.25483.107.127.25532,766
21683.107.128.0/1783.107.128.1 to 83.107.255.25483.107.255.25532,766
21783.108.0.0/1783.108.0.1 to 83.108.127.25483.108.127.25532,766
21883.108.128.0/1783.108.128.1 to 83.108.255.25483.108.255.25532,766
21983.109.0.0/1783.109.0.1 to 83.109.127.25483.109.127.25532,766
22083.109.128.0/1783.109.128.1 to 83.109.255.25483.109.255.25532,766
22183.110.0.0/1783.110.0.1 to 83.110.127.25483.110.127.25532,766
22283.110.128.0/1783.110.128.1 to 83.110.255.25483.110.255.25532,766
22383.111.0.0/1783.111.0.1 to 83.111.127.25483.111.127.25532,766
22483.111.128.0/1783.111.128.1 to 83.111.255.25483.111.255.25532,766
22583.112.0.0/1783.112.0.1 to 83.112.127.25483.112.127.25532,766
22683.112.128.0/1783.112.128.1 to 83.112.255.25483.112.255.25532,766
22783.113.0.0/1783.113.0.1 to 83.113.127.25483.113.127.25532,766
22883.113.128.0/1783.113.128.1 to 83.113.255.25483.113.255.25532,766
22983.114.0.0/1783.114.0.1 to 83.114.127.25483.114.127.25532,766
23083.114.128.0/1783.114.128.1 to 83.114.255.25483.114.255.25532,766
23183.115.0.0/1783.115.0.1 to 83.115.127.25483.115.127.25532,766
23283.115.128.0/1783.115.128.1 to 83.115.255.25483.115.255.25532,766
23383.116.0.0/1783.116.0.1 to 83.116.127.25483.116.127.25532,766
23483.116.128.0/1783.116.128.1 to 83.116.255.25483.116.255.25532,766
23583.117.0.0/1783.117.0.1 to 83.117.127.25483.117.127.25532,766
23683.117.128.0/1783.117.128.1 to 83.117.255.25483.117.255.25532,766
23783.118.0.0/1783.118.0.1 to 83.118.127.25483.118.127.25532,766
23883.118.128.0/1783.118.128.1 to 83.118.255.25483.118.255.25532,766
23983.119.0.0/1783.119.0.1 to 83.119.127.25483.119.127.25532,766
24083.119.128.0/1783.119.128.1 to 83.119.255.25483.119.255.25532,766
24183.120.0.0/1783.120.0.1 to 83.120.127.25483.120.127.25532,766
24283.120.128.0/1783.120.128.1 to 83.120.255.25483.120.255.25532,766
24383.121.0.0/1783.121.0.1 to 83.121.127.25483.121.127.25532,766
24483.121.128.0/1783.121.128.1 to 83.121.255.25483.121.255.25532,766
24583.122.0.0/1783.122.0.1 to 83.122.127.25483.122.127.25532,766
24683.122.128.0/1783.122.128.1 to 83.122.255.25483.122.255.25532,766
24783.123.0.0/1783.123.0.1 to 83.123.127.25483.123.127.25532,766
24883.123.128.0/1783.123.128.1 to 83.123.255.25483.123.255.25532,766
24983.124.0.0/1783.124.0.1 to 83.124.127.25483.124.127.25532,766
25083.124.128.0/1783.124.128.1 to 83.124.255.25483.124.255.25532,766
25183.125.0.0/1783.125.0.1 to 83.125.127.25483.125.127.25532,766
25283.125.128.0/1783.125.128.1 to 83.125.255.25483.125.255.25532,766
25383.126.0.0/1783.126.0.1 to 83.126.127.25483.126.127.25532,766
25483.126.128.0/1783.126.128.1 to 83.126.255.25483.126.255.25532,766
25583.127.0.0/1783.127.0.1 to 83.127.127.25483.127.127.25532,766
25683.127.128.0/1783.127.128.1 to 83.127.255.25483.127.255.25532,766

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