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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.

Network83.3.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
83.3.0.0
Broadcast address
83.3.255.255
First usable
83.3.0.1
Last usable
83.3.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 53030000 · Integer 1392705536 to 1392771071
Reverse DNS zone
3.83.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010011.00000011..00000000.0000000083.3.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01010011.00000011..00000000.0000000083.3.0.0
Broadcast01010011.00000011..11111111.1111111183.3.255.255
Split into smaller subnets/26

83.3.0.0/16 makes 1,024 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
183.3.0.0/2683.3.0.1 to 83.3.0.6283.3.0.6362
283.3.0.64/2683.3.0.65 to 83.3.0.12683.3.0.12762
383.3.0.128/2683.3.0.129 to 83.3.0.19083.3.0.19162
483.3.0.192/2683.3.0.193 to 83.3.0.25483.3.0.25562
583.3.1.0/2683.3.1.1 to 83.3.1.6283.3.1.6362
683.3.1.64/2683.3.1.65 to 83.3.1.12683.3.1.12762
783.3.1.128/2683.3.1.129 to 83.3.1.19083.3.1.19162
883.3.1.192/2683.3.1.193 to 83.3.1.25483.3.1.25562
983.3.2.0/2683.3.2.1 to 83.3.2.6283.3.2.6362
1083.3.2.64/2683.3.2.65 to 83.3.2.12683.3.2.12762
1183.3.2.128/2683.3.2.129 to 83.3.2.19083.3.2.19162
1283.3.2.192/2683.3.2.193 to 83.3.2.25483.3.2.25562
1383.3.3.0/2683.3.3.1 to 83.3.3.6283.3.3.6362
1483.3.3.64/2683.3.3.65 to 83.3.3.12683.3.3.12762
1583.3.3.128/2683.3.3.129 to 83.3.3.19083.3.3.19162
1683.3.3.192/2683.3.3.193 to 83.3.3.25483.3.3.25562
1783.3.4.0/2683.3.4.1 to 83.3.4.6283.3.4.6362
1883.3.4.64/2683.3.4.65 to 83.3.4.12683.3.4.12762
1983.3.4.128/2683.3.4.129 to 83.3.4.19083.3.4.19162
2083.3.4.192/2683.3.4.193 to 83.3.4.25483.3.4.25562
2183.3.5.0/2683.3.5.1 to 83.3.5.6283.3.5.6362
2283.3.5.64/2683.3.5.65 to 83.3.5.12683.3.5.12762
2383.3.5.128/2683.3.5.129 to 83.3.5.19083.3.5.19162
2483.3.5.192/2683.3.5.193 to 83.3.5.25483.3.5.25562
2583.3.6.0/2683.3.6.1 to 83.3.6.6283.3.6.6362
2683.3.6.64/2683.3.6.65 to 83.3.6.12683.3.6.12762
2783.3.6.128/2683.3.6.129 to 83.3.6.19083.3.6.19162
2883.3.6.192/2683.3.6.193 to 83.3.6.25483.3.6.25562
2983.3.7.0/2683.3.7.1 to 83.3.7.6283.3.7.6362
3083.3.7.64/2683.3.7.65 to 83.3.7.12683.3.7.12762
3183.3.7.128/2683.3.7.129 to 83.3.7.19083.3.7.19162
3283.3.7.192/2683.3.7.193 to 83.3.7.25483.3.7.25562
3383.3.8.0/2683.3.8.1 to 83.3.8.6283.3.8.6362
3483.3.8.64/2683.3.8.65 to 83.3.8.12683.3.8.12762
3583.3.8.128/2683.3.8.129 to 83.3.8.19083.3.8.19162
3683.3.8.192/2683.3.8.193 to 83.3.8.25483.3.8.25562
3783.3.9.0/2683.3.9.1 to 83.3.9.6283.3.9.6362
3883.3.9.64/2683.3.9.65 to 83.3.9.12683.3.9.12762
3983.3.9.128/2683.3.9.129 to 83.3.9.19083.3.9.19162
4083.3.9.192/2683.3.9.193 to 83.3.9.25483.3.9.25562
4183.3.10.0/2683.3.10.1 to 83.3.10.6283.3.10.6362
4283.3.10.64/2683.3.10.65 to 83.3.10.12683.3.10.12762
4383.3.10.128/2683.3.10.129 to 83.3.10.19083.3.10.19162
4483.3.10.192/2683.3.10.193 to 83.3.10.25483.3.10.25562
4583.3.11.0/2683.3.11.1 to 83.3.11.6283.3.11.6362
4683.3.11.64/2683.3.11.65 to 83.3.11.12683.3.11.12762
4783.3.11.128/2683.3.11.129 to 83.3.11.19083.3.11.19162
4883.3.11.192/2683.3.11.193 to 83.3.11.25483.3.11.25562
4983.3.12.0/2683.3.12.1 to 83.3.12.6283.3.12.6362
5083.3.12.64/2683.3.12.65 to 83.3.12.12683.3.12.12762
5183.3.12.128/2683.3.12.129 to 83.3.12.19083.3.12.19162
5283.3.12.192/2683.3.12.193 to 83.3.12.25483.3.12.25562
5383.3.13.0/2683.3.13.1 to 83.3.13.6283.3.13.6362
5483.3.13.64/2683.3.13.65 to 83.3.13.12683.3.13.12762
5583.3.13.128/2683.3.13.129 to 83.3.13.19083.3.13.19162
5683.3.13.192/2683.3.13.193 to 83.3.13.25483.3.13.25562
5783.3.14.0/2683.3.14.1 to 83.3.14.6283.3.14.6362
5883.3.14.64/2683.3.14.65 to 83.3.14.12683.3.14.12762
5983.3.14.128/2683.3.14.129 to 83.3.14.19083.3.14.19162
6083.3.14.192/2683.3.14.193 to 83.3.14.25483.3.14.25562
6183.3.15.0/2683.3.15.1 to 83.3.15.6283.3.15.6362
6283.3.15.64/2683.3.15.65 to 83.3.15.12683.3.15.12762
6383.3.15.128/2683.3.15.129 to 83.3.15.19083.3.15.19162
6483.3.15.192/2683.3.15.193 to 83.3.15.25483.3.15.25562
6583.3.16.0/2683.3.16.1 to 83.3.16.6283.3.16.6362
6683.3.16.64/2683.3.16.65 to 83.3.16.12683.3.16.12762
6783.3.16.128/2683.3.16.129 to 83.3.16.19083.3.16.19162
6883.3.16.192/2683.3.16.193 to 83.3.16.25483.3.16.25562
6983.3.17.0/2683.3.17.1 to 83.3.17.6283.3.17.6362
7083.3.17.64/2683.3.17.65 to 83.3.17.12683.3.17.12762
7183.3.17.128/2683.3.17.129 to 83.3.17.19083.3.17.19162
7283.3.17.192/2683.3.17.193 to 83.3.17.25483.3.17.25562
7383.3.18.0/2683.3.18.1 to 83.3.18.6283.3.18.6362
7483.3.18.64/2683.3.18.65 to 83.3.18.12683.3.18.12762
7583.3.18.128/2683.3.18.129 to 83.3.18.19083.3.18.19162
7683.3.18.192/2683.3.18.193 to 83.3.18.25483.3.18.25562
7783.3.19.0/2683.3.19.1 to 83.3.19.6283.3.19.6362
7883.3.19.64/2683.3.19.65 to 83.3.19.12683.3.19.12762
7983.3.19.128/2683.3.19.129 to 83.3.19.19083.3.19.19162
8083.3.19.192/2683.3.19.193 to 83.3.19.25483.3.19.25562
8183.3.20.0/2683.3.20.1 to 83.3.20.6283.3.20.6362
8283.3.20.64/2683.3.20.65 to 83.3.20.12683.3.20.12762
8383.3.20.128/2683.3.20.129 to 83.3.20.19083.3.20.19162
8483.3.20.192/2683.3.20.193 to 83.3.20.25483.3.20.25562
8583.3.21.0/2683.3.21.1 to 83.3.21.6283.3.21.6362
8683.3.21.64/2683.3.21.65 to 83.3.21.12683.3.21.12762
8783.3.21.128/2683.3.21.129 to 83.3.21.19083.3.21.19162
8883.3.21.192/2683.3.21.193 to 83.3.21.25483.3.21.25562
8983.3.22.0/2683.3.22.1 to 83.3.22.6283.3.22.6362
9083.3.22.64/2683.3.22.65 to 83.3.22.12683.3.22.12762
9183.3.22.128/2683.3.22.129 to 83.3.22.19083.3.22.19162
9283.3.22.192/2683.3.22.193 to 83.3.22.25483.3.22.25562
9383.3.23.0/2683.3.23.1 to 83.3.23.6283.3.23.6362
9483.3.23.64/2683.3.23.65 to 83.3.23.12683.3.23.12762
9583.3.23.128/2683.3.23.129 to 83.3.23.19083.3.23.19162
9683.3.23.192/2683.3.23.193 to 83.3.23.25483.3.23.25562
9783.3.24.0/2683.3.24.1 to 83.3.24.6283.3.24.6362
9883.3.24.64/2683.3.24.65 to 83.3.24.12683.3.24.12762
9983.3.24.128/2683.3.24.129 to 83.3.24.19083.3.24.19162
10083.3.24.192/2683.3.24.193 to 83.3.24.25483.3.24.25562
10183.3.25.0/2683.3.25.1 to 83.3.25.6283.3.25.6362
10283.3.25.64/2683.3.25.65 to 83.3.25.12683.3.25.12762
10383.3.25.128/2683.3.25.129 to 83.3.25.19083.3.25.19162
10483.3.25.192/2683.3.25.193 to 83.3.25.25483.3.25.25562
10583.3.26.0/2683.3.26.1 to 83.3.26.6283.3.26.6362
10683.3.26.64/2683.3.26.65 to 83.3.26.12683.3.26.12762
10783.3.26.128/2683.3.26.129 to 83.3.26.19083.3.26.19162
10883.3.26.192/2683.3.26.193 to 83.3.26.25483.3.26.25562
10983.3.27.0/2683.3.27.1 to 83.3.27.6283.3.27.6362
11083.3.27.64/2683.3.27.65 to 83.3.27.12683.3.27.12762
11183.3.27.128/2683.3.27.129 to 83.3.27.19083.3.27.19162
11283.3.27.192/2683.3.27.193 to 83.3.27.25483.3.27.25562
11383.3.28.0/2683.3.28.1 to 83.3.28.6283.3.28.6362
11483.3.28.64/2683.3.28.65 to 83.3.28.12683.3.28.12762
11583.3.28.128/2683.3.28.129 to 83.3.28.19083.3.28.19162
11683.3.28.192/2683.3.28.193 to 83.3.28.25483.3.28.25562
11783.3.29.0/2683.3.29.1 to 83.3.29.6283.3.29.6362
11883.3.29.64/2683.3.29.65 to 83.3.29.12683.3.29.12762
11983.3.29.128/2683.3.29.129 to 83.3.29.19083.3.29.19162
12083.3.29.192/2683.3.29.193 to 83.3.29.25483.3.29.25562
12183.3.30.0/2683.3.30.1 to 83.3.30.6283.3.30.6362
12283.3.30.64/2683.3.30.65 to 83.3.30.12683.3.30.12762
12383.3.30.128/2683.3.30.129 to 83.3.30.19083.3.30.19162
12483.3.30.192/2683.3.30.193 to 83.3.30.25483.3.30.25562
12583.3.31.0/2683.3.31.1 to 83.3.31.6283.3.31.6362
12683.3.31.64/2683.3.31.65 to 83.3.31.12683.3.31.12762
12783.3.31.128/2683.3.31.129 to 83.3.31.19083.3.31.19162
12883.3.31.192/2683.3.31.193 to 83.3.31.25483.3.31.25562
12983.3.32.0/2683.3.32.1 to 83.3.32.6283.3.32.6362
13083.3.32.64/2683.3.32.65 to 83.3.32.12683.3.32.12762
13183.3.32.128/2683.3.32.129 to 83.3.32.19083.3.32.19162
13283.3.32.192/2683.3.32.193 to 83.3.32.25483.3.32.25562
13383.3.33.0/2683.3.33.1 to 83.3.33.6283.3.33.6362
13483.3.33.64/2683.3.33.65 to 83.3.33.12683.3.33.12762
13583.3.33.128/2683.3.33.129 to 83.3.33.19083.3.33.19162
13683.3.33.192/2683.3.33.193 to 83.3.33.25483.3.33.25562
13783.3.34.0/2683.3.34.1 to 83.3.34.6283.3.34.6362
13883.3.34.64/2683.3.34.65 to 83.3.34.12683.3.34.12762
13983.3.34.128/2683.3.34.129 to 83.3.34.19083.3.34.19162
14083.3.34.192/2683.3.34.193 to 83.3.34.25483.3.34.25562
14183.3.35.0/2683.3.35.1 to 83.3.35.6283.3.35.6362
14283.3.35.64/2683.3.35.65 to 83.3.35.12683.3.35.12762
14383.3.35.128/2683.3.35.129 to 83.3.35.19083.3.35.19162
14483.3.35.192/2683.3.35.193 to 83.3.35.25483.3.35.25562
14583.3.36.0/2683.3.36.1 to 83.3.36.6283.3.36.6362
14683.3.36.64/2683.3.36.65 to 83.3.36.12683.3.36.12762
14783.3.36.128/2683.3.36.129 to 83.3.36.19083.3.36.19162
14883.3.36.192/2683.3.36.193 to 83.3.36.25483.3.36.25562
14983.3.37.0/2683.3.37.1 to 83.3.37.6283.3.37.6362
15083.3.37.64/2683.3.37.65 to 83.3.37.12683.3.37.12762
15183.3.37.128/2683.3.37.129 to 83.3.37.19083.3.37.19162
15283.3.37.192/2683.3.37.193 to 83.3.37.25483.3.37.25562
15383.3.38.0/2683.3.38.1 to 83.3.38.6283.3.38.6362
15483.3.38.64/2683.3.38.65 to 83.3.38.12683.3.38.12762
15583.3.38.128/2683.3.38.129 to 83.3.38.19083.3.38.19162
15683.3.38.192/2683.3.38.193 to 83.3.38.25483.3.38.25562
15783.3.39.0/2683.3.39.1 to 83.3.39.6283.3.39.6362
15883.3.39.64/2683.3.39.65 to 83.3.39.12683.3.39.12762
15983.3.39.128/2683.3.39.129 to 83.3.39.19083.3.39.19162
16083.3.39.192/2683.3.39.193 to 83.3.39.25483.3.39.25562
16183.3.40.0/2683.3.40.1 to 83.3.40.6283.3.40.6362
16283.3.40.64/2683.3.40.65 to 83.3.40.12683.3.40.12762
16383.3.40.128/2683.3.40.129 to 83.3.40.19083.3.40.19162
16483.3.40.192/2683.3.40.193 to 83.3.40.25483.3.40.25562
16583.3.41.0/2683.3.41.1 to 83.3.41.6283.3.41.6362
16683.3.41.64/2683.3.41.65 to 83.3.41.12683.3.41.12762
16783.3.41.128/2683.3.41.129 to 83.3.41.19083.3.41.19162
16883.3.41.192/2683.3.41.193 to 83.3.41.25483.3.41.25562
16983.3.42.0/2683.3.42.1 to 83.3.42.6283.3.42.6362
17083.3.42.64/2683.3.42.65 to 83.3.42.12683.3.42.12762
17183.3.42.128/2683.3.42.129 to 83.3.42.19083.3.42.19162
17283.3.42.192/2683.3.42.193 to 83.3.42.25483.3.42.25562
17383.3.43.0/2683.3.43.1 to 83.3.43.6283.3.43.6362
17483.3.43.64/2683.3.43.65 to 83.3.43.12683.3.43.12762
17583.3.43.128/2683.3.43.129 to 83.3.43.19083.3.43.19162
17683.3.43.192/2683.3.43.193 to 83.3.43.25483.3.43.25562
17783.3.44.0/2683.3.44.1 to 83.3.44.6283.3.44.6362
17883.3.44.64/2683.3.44.65 to 83.3.44.12683.3.44.12762
17983.3.44.128/2683.3.44.129 to 83.3.44.19083.3.44.19162
18083.3.44.192/2683.3.44.193 to 83.3.44.25483.3.44.25562
18183.3.45.0/2683.3.45.1 to 83.3.45.6283.3.45.6362
18283.3.45.64/2683.3.45.65 to 83.3.45.12683.3.45.12762
18383.3.45.128/2683.3.45.129 to 83.3.45.19083.3.45.19162
18483.3.45.192/2683.3.45.193 to 83.3.45.25483.3.45.25562
18583.3.46.0/2683.3.46.1 to 83.3.46.6283.3.46.6362
18683.3.46.64/2683.3.46.65 to 83.3.46.12683.3.46.12762
18783.3.46.128/2683.3.46.129 to 83.3.46.19083.3.46.19162
18883.3.46.192/2683.3.46.193 to 83.3.46.25483.3.46.25562
18983.3.47.0/2683.3.47.1 to 83.3.47.6283.3.47.6362
19083.3.47.64/2683.3.47.65 to 83.3.47.12683.3.47.12762
19183.3.47.128/2683.3.47.129 to 83.3.47.19083.3.47.19162
19283.3.47.192/2683.3.47.193 to 83.3.47.25483.3.47.25562
19383.3.48.0/2683.3.48.1 to 83.3.48.6283.3.48.6362
19483.3.48.64/2683.3.48.65 to 83.3.48.12683.3.48.12762
19583.3.48.128/2683.3.48.129 to 83.3.48.19083.3.48.19162
19683.3.48.192/2683.3.48.193 to 83.3.48.25483.3.48.25562
19783.3.49.0/2683.3.49.1 to 83.3.49.6283.3.49.6362
19883.3.49.64/2683.3.49.65 to 83.3.49.12683.3.49.12762
19983.3.49.128/2683.3.49.129 to 83.3.49.19083.3.49.19162
20083.3.49.192/2683.3.49.193 to 83.3.49.25483.3.49.25562
20183.3.50.0/2683.3.50.1 to 83.3.50.6283.3.50.6362
20283.3.50.64/2683.3.50.65 to 83.3.50.12683.3.50.12762
20383.3.50.128/2683.3.50.129 to 83.3.50.19083.3.50.19162
20483.3.50.192/2683.3.50.193 to 83.3.50.25483.3.50.25562
20583.3.51.0/2683.3.51.1 to 83.3.51.6283.3.51.6362
20683.3.51.64/2683.3.51.65 to 83.3.51.12683.3.51.12762
20783.3.51.128/2683.3.51.129 to 83.3.51.19083.3.51.19162
20883.3.51.192/2683.3.51.193 to 83.3.51.25483.3.51.25562
20983.3.52.0/2683.3.52.1 to 83.3.52.6283.3.52.6362
21083.3.52.64/2683.3.52.65 to 83.3.52.12683.3.52.12762
21183.3.52.128/2683.3.52.129 to 83.3.52.19083.3.52.19162
21283.3.52.192/2683.3.52.193 to 83.3.52.25483.3.52.25562
21383.3.53.0/2683.3.53.1 to 83.3.53.6283.3.53.6362
21483.3.53.64/2683.3.53.65 to 83.3.53.12683.3.53.12762
21583.3.53.128/2683.3.53.129 to 83.3.53.19083.3.53.19162
21683.3.53.192/2683.3.53.193 to 83.3.53.25483.3.53.25562
21783.3.54.0/2683.3.54.1 to 83.3.54.6283.3.54.6362
21883.3.54.64/2683.3.54.65 to 83.3.54.12683.3.54.12762
21983.3.54.128/2683.3.54.129 to 83.3.54.19083.3.54.19162
22083.3.54.192/2683.3.54.193 to 83.3.54.25483.3.54.25562
22183.3.55.0/2683.3.55.1 to 83.3.55.6283.3.55.6362
22283.3.55.64/2683.3.55.65 to 83.3.55.12683.3.55.12762
22383.3.55.128/2683.3.55.129 to 83.3.55.19083.3.55.19162
22483.3.55.192/2683.3.55.193 to 83.3.55.25483.3.55.25562
22583.3.56.0/2683.3.56.1 to 83.3.56.6283.3.56.6362
22683.3.56.64/2683.3.56.65 to 83.3.56.12683.3.56.12762
22783.3.56.128/2683.3.56.129 to 83.3.56.19083.3.56.19162
22883.3.56.192/2683.3.56.193 to 83.3.56.25483.3.56.25562
22983.3.57.0/2683.3.57.1 to 83.3.57.6283.3.57.6362
23083.3.57.64/2683.3.57.65 to 83.3.57.12683.3.57.12762
23183.3.57.128/2683.3.57.129 to 83.3.57.19083.3.57.19162
23283.3.57.192/2683.3.57.193 to 83.3.57.25483.3.57.25562
23383.3.58.0/2683.3.58.1 to 83.3.58.6283.3.58.6362
23483.3.58.64/2683.3.58.65 to 83.3.58.12683.3.58.12762
23583.3.58.128/2683.3.58.129 to 83.3.58.19083.3.58.19162
23683.3.58.192/2683.3.58.193 to 83.3.58.25483.3.58.25562
23783.3.59.0/2683.3.59.1 to 83.3.59.6283.3.59.6362
23883.3.59.64/2683.3.59.65 to 83.3.59.12683.3.59.12762
23983.3.59.128/2683.3.59.129 to 83.3.59.19083.3.59.19162
24083.3.59.192/2683.3.59.193 to 83.3.59.25483.3.59.25562
24183.3.60.0/2683.3.60.1 to 83.3.60.6283.3.60.6362
24283.3.60.64/2683.3.60.65 to 83.3.60.12683.3.60.12762
24383.3.60.128/2683.3.60.129 to 83.3.60.19083.3.60.19162
24483.3.60.192/2683.3.60.193 to 83.3.60.25483.3.60.25562
24583.3.61.0/2683.3.61.1 to 83.3.61.6283.3.61.6362
24683.3.61.64/2683.3.61.65 to 83.3.61.12683.3.61.12762
24783.3.61.128/2683.3.61.129 to 83.3.61.19083.3.61.19162
24883.3.61.192/2683.3.61.193 to 83.3.61.25483.3.61.25562
24983.3.62.0/2683.3.62.1 to 83.3.62.6283.3.62.6362
25083.3.62.64/2683.3.62.65 to 83.3.62.12683.3.62.12762
25183.3.62.128/2683.3.62.129 to 83.3.62.19083.3.62.19162
25283.3.62.192/2683.3.62.193 to 83.3.62.25483.3.62.25562
25383.3.63.0/2683.3.63.1 to 83.3.63.6283.3.63.6362
25483.3.63.64/2683.3.63.65 to 83.3.63.12683.3.63.12762
25583.3.63.128/2683.3.63.129 to 83.3.63.19083.3.63.19162
25683.3.63.192/2683.3.63.193 to 83.3.63.25483.3.63.25562

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