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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/18
/10 (2)/11 (4)/12 (8)/13 (16)/14 (32)/15 (64)/16 (128)/17 (256)/18 (512)/19 (1,024)/20 (2,048)/21 (4,096)

83.0.0.0/9 makes 512 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
183.0.0.0/1883.0.0.1 to 83.0.63.25483.0.63.25516,382
283.0.64.0/1883.0.64.1 to 83.0.127.25483.0.127.25516,382
383.0.128.0/1883.0.128.1 to 83.0.191.25483.0.191.25516,382
483.0.192.0/1883.0.192.1 to 83.0.255.25483.0.255.25516,382
583.1.0.0/1883.1.0.1 to 83.1.63.25483.1.63.25516,382
683.1.64.0/1883.1.64.1 to 83.1.127.25483.1.127.25516,382
783.1.128.0/1883.1.128.1 to 83.1.191.25483.1.191.25516,382
883.1.192.0/1883.1.192.1 to 83.1.255.25483.1.255.25516,382
983.2.0.0/1883.2.0.1 to 83.2.63.25483.2.63.25516,382
1083.2.64.0/1883.2.64.1 to 83.2.127.25483.2.127.25516,382
1183.2.128.0/1883.2.128.1 to 83.2.191.25483.2.191.25516,382
1283.2.192.0/1883.2.192.1 to 83.2.255.25483.2.255.25516,382
1383.3.0.0/1883.3.0.1 to 83.3.63.25483.3.63.25516,382
1483.3.64.0/1883.3.64.1 to 83.3.127.25483.3.127.25516,382
1583.3.128.0/1883.3.128.1 to 83.3.191.25483.3.191.25516,382
1683.3.192.0/1883.3.192.1 to 83.3.255.25483.3.255.25516,382
1783.4.0.0/1883.4.0.1 to 83.4.63.25483.4.63.25516,382
1883.4.64.0/1883.4.64.1 to 83.4.127.25483.4.127.25516,382
1983.4.128.0/1883.4.128.1 to 83.4.191.25483.4.191.25516,382
2083.4.192.0/1883.4.192.1 to 83.4.255.25483.4.255.25516,382
2183.5.0.0/1883.5.0.1 to 83.5.63.25483.5.63.25516,382
2283.5.64.0/1883.5.64.1 to 83.5.127.25483.5.127.25516,382
2383.5.128.0/1883.5.128.1 to 83.5.191.25483.5.191.25516,382
2483.5.192.0/1883.5.192.1 to 83.5.255.25483.5.255.25516,382
2583.6.0.0/1883.6.0.1 to 83.6.63.25483.6.63.25516,382
2683.6.64.0/1883.6.64.1 to 83.6.127.25483.6.127.25516,382
2783.6.128.0/1883.6.128.1 to 83.6.191.25483.6.191.25516,382
2883.6.192.0/1883.6.192.1 to 83.6.255.25483.6.255.25516,382
2983.7.0.0/1883.7.0.1 to 83.7.63.25483.7.63.25516,382
3083.7.64.0/1883.7.64.1 to 83.7.127.25483.7.127.25516,382
3183.7.128.0/1883.7.128.1 to 83.7.191.25483.7.191.25516,382
3283.7.192.0/1883.7.192.1 to 83.7.255.25483.7.255.25516,382
3383.8.0.0/1883.8.0.1 to 83.8.63.25483.8.63.25516,382
3483.8.64.0/1883.8.64.1 to 83.8.127.25483.8.127.25516,382
3583.8.128.0/1883.8.128.1 to 83.8.191.25483.8.191.25516,382
3683.8.192.0/1883.8.192.1 to 83.8.255.25483.8.255.25516,382
3783.9.0.0/1883.9.0.1 to 83.9.63.25483.9.63.25516,382
3883.9.64.0/1883.9.64.1 to 83.9.127.25483.9.127.25516,382
3983.9.128.0/1883.9.128.1 to 83.9.191.25483.9.191.25516,382
4083.9.192.0/1883.9.192.1 to 83.9.255.25483.9.255.25516,382
4183.10.0.0/1883.10.0.1 to 83.10.63.25483.10.63.25516,382
4283.10.64.0/1883.10.64.1 to 83.10.127.25483.10.127.25516,382
4383.10.128.0/1883.10.128.1 to 83.10.191.25483.10.191.25516,382
4483.10.192.0/1883.10.192.1 to 83.10.255.25483.10.255.25516,382
4583.11.0.0/1883.11.0.1 to 83.11.63.25483.11.63.25516,382
4683.11.64.0/1883.11.64.1 to 83.11.127.25483.11.127.25516,382
4783.11.128.0/1883.11.128.1 to 83.11.191.25483.11.191.25516,382
4883.11.192.0/1883.11.192.1 to 83.11.255.25483.11.255.25516,382
4983.12.0.0/1883.12.0.1 to 83.12.63.25483.12.63.25516,382
5083.12.64.0/1883.12.64.1 to 83.12.127.25483.12.127.25516,382
5183.12.128.0/1883.12.128.1 to 83.12.191.25483.12.191.25516,382
5283.12.192.0/1883.12.192.1 to 83.12.255.25483.12.255.25516,382
5383.13.0.0/1883.13.0.1 to 83.13.63.25483.13.63.25516,382
5483.13.64.0/1883.13.64.1 to 83.13.127.25483.13.127.25516,382
5583.13.128.0/1883.13.128.1 to 83.13.191.25483.13.191.25516,382
5683.13.192.0/1883.13.192.1 to 83.13.255.25483.13.255.25516,382
5783.14.0.0/1883.14.0.1 to 83.14.63.25483.14.63.25516,382
5883.14.64.0/1883.14.64.1 to 83.14.127.25483.14.127.25516,382
5983.14.128.0/1883.14.128.1 to 83.14.191.25483.14.191.25516,382
6083.14.192.0/1883.14.192.1 to 83.14.255.25483.14.255.25516,382
6183.15.0.0/1883.15.0.1 to 83.15.63.25483.15.63.25516,382
6283.15.64.0/1883.15.64.1 to 83.15.127.25483.15.127.25516,382
6383.15.128.0/1883.15.128.1 to 83.15.191.25483.15.191.25516,382
6483.15.192.0/1883.15.192.1 to 83.15.255.25483.15.255.25516,382
6583.16.0.0/1883.16.0.1 to 83.16.63.25483.16.63.25516,382
6683.16.64.0/1883.16.64.1 to 83.16.127.25483.16.127.25516,382
6783.16.128.0/1883.16.128.1 to 83.16.191.25483.16.191.25516,382
6883.16.192.0/1883.16.192.1 to 83.16.255.25483.16.255.25516,382
6983.17.0.0/1883.17.0.1 to 83.17.63.25483.17.63.25516,382
7083.17.64.0/1883.17.64.1 to 83.17.127.25483.17.127.25516,382
7183.17.128.0/1883.17.128.1 to 83.17.191.25483.17.191.25516,382
7283.17.192.0/1883.17.192.1 to 83.17.255.25483.17.255.25516,382
7383.18.0.0/1883.18.0.1 to 83.18.63.25483.18.63.25516,382
7483.18.64.0/1883.18.64.1 to 83.18.127.25483.18.127.25516,382
7583.18.128.0/1883.18.128.1 to 83.18.191.25483.18.191.25516,382
7683.18.192.0/1883.18.192.1 to 83.18.255.25483.18.255.25516,382
7783.19.0.0/1883.19.0.1 to 83.19.63.25483.19.63.25516,382
7883.19.64.0/1883.19.64.1 to 83.19.127.25483.19.127.25516,382
7983.19.128.0/1883.19.128.1 to 83.19.191.25483.19.191.25516,382
8083.19.192.0/1883.19.192.1 to 83.19.255.25483.19.255.25516,382
8183.20.0.0/1883.20.0.1 to 83.20.63.25483.20.63.25516,382
8283.20.64.0/1883.20.64.1 to 83.20.127.25483.20.127.25516,382
8383.20.128.0/1883.20.128.1 to 83.20.191.25483.20.191.25516,382
8483.20.192.0/1883.20.192.1 to 83.20.255.25483.20.255.25516,382
8583.21.0.0/1883.21.0.1 to 83.21.63.25483.21.63.25516,382
8683.21.64.0/1883.21.64.1 to 83.21.127.25483.21.127.25516,382
8783.21.128.0/1883.21.128.1 to 83.21.191.25483.21.191.25516,382
8883.21.192.0/1883.21.192.1 to 83.21.255.25483.21.255.25516,382
8983.22.0.0/1883.22.0.1 to 83.22.63.25483.22.63.25516,382
9083.22.64.0/1883.22.64.1 to 83.22.127.25483.22.127.25516,382
9183.22.128.0/1883.22.128.1 to 83.22.191.25483.22.191.25516,382
9283.22.192.0/1883.22.192.1 to 83.22.255.25483.22.255.25516,382
9383.23.0.0/1883.23.0.1 to 83.23.63.25483.23.63.25516,382
9483.23.64.0/1883.23.64.1 to 83.23.127.25483.23.127.25516,382
9583.23.128.0/1883.23.128.1 to 83.23.191.25483.23.191.25516,382
9683.23.192.0/1883.23.192.1 to 83.23.255.25483.23.255.25516,382
9783.24.0.0/1883.24.0.1 to 83.24.63.25483.24.63.25516,382
9883.24.64.0/1883.24.64.1 to 83.24.127.25483.24.127.25516,382
9983.24.128.0/1883.24.128.1 to 83.24.191.25483.24.191.25516,382
10083.24.192.0/1883.24.192.1 to 83.24.255.25483.24.255.25516,382
10183.25.0.0/1883.25.0.1 to 83.25.63.25483.25.63.25516,382
10283.25.64.0/1883.25.64.1 to 83.25.127.25483.25.127.25516,382
10383.25.128.0/1883.25.128.1 to 83.25.191.25483.25.191.25516,382
10483.25.192.0/1883.25.192.1 to 83.25.255.25483.25.255.25516,382
10583.26.0.0/1883.26.0.1 to 83.26.63.25483.26.63.25516,382
10683.26.64.0/1883.26.64.1 to 83.26.127.25483.26.127.25516,382
10783.26.128.0/1883.26.128.1 to 83.26.191.25483.26.191.25516,382
10883.26.192.0/1883.26.192.1 to 83.26.255.25483.26.255.25516,382
10983.27.0.0/1883.27.0.1 to 83.27.63.25483.27.63.25516,382
11083.27.64.0/1883.27.64.1 to 83.27.127.25483.27.127.25516,382
11183.27.128.0/1883.27.128.1 to 83.27.191.25483.27.191.25516,382
11283.27.192.0/1883.27.192.1 to 83.27.255.25483.27.255.25516,382
11383.28.0.0/1883.28.0.1 to 83.28.63.25483.28.63.25516,382
11483.28.64.0/1883.28.64.1 to 83.28.127.25483.28.127.25516,382
11583.28.128.0/1883.28.128.1 to 83.28.191.25483.28.191.25516,382
11683.28.192.0/1883.28.192.1 to 83.28.255.25483.28.255.25516,382
11783.29.0.0/1883.29.0.1 to 83.29.63.25483.29.63.25516,382
11883.29.64.0/1883.29.64.1 to 83.29.127.25483.29.127.25516,382
11983.29.128.0/1883.29.128.1 to 83.29.191.25483.29.191.25516,382
12083.29.192.0/1883.29.192.1 to 83.29.255.25483.29.255.25516,382
12183.30.0.0/1883.30.0.1 to 83.30.63.25483.30.63.25516,382
12283.30.64.0/1883.30.64.1 to 83.30.127.25483.30.127.25516,382
12383.30.128.0/1883.30.128.1 to 83.30.191.25483.30.191.25516,382
12483.30.192.0/1883.30.192.1 to 83.30.255.25483.30.255.25516,382
12583.31.0.0/1883.31.0.1 to 83.31.63.25483.31.63.25516,382
12683.31.64.0/1883.31.64.1 to 83.31.127.25483.31.127.25516,382
12783.31.128.0/1883.31.128.1 to 83.31.191.25483.31.191.25516,382
12883.31.192.0/1883.31.192.1 to 83.31.255.25483.31.255.25516,382
12983.32.0.0/1883.32.0.1 to 83.32.63.25483.32.63.25516,382
13083.32.64.0/1883.32.64.1 to 83.32.127.25483.32.127.25516,382
13183.32.128.0/1883.32.128.1 to 83.32.191.25483.32.191.25516,382
13283.32.192.0/1883.32.192.1 to 83.32.255.25483.32.255.25516,382
13383.33.0.0/1883.33.0.1 to 83.33.63.25483.33.63.25516,382
13483.33.64.0/1883.33.64.1 to 83.33.127.25483.33.127.25516,382
13583.33.128.0/1883.33.128.1 to 83.33.191.25483.33.191.25516,382
13683.33.192.0/1883.33.192.1 to 83.33.255.25483.33.255.25516,382
13783.34.0.0/1883.34.0.1 to 83.34.63.25483.34.63.25516,382
13883.34.64.0/1883.34.64.1 to 83.34.127.25483.34.127.25516,382
13983.34.128.0/1883.34.128.1 to 83.34.191.25483.34.191.25516,382
14083.34.192.0/1883.34.192.1 to 83.34.255.25483.34.255.25516,382
14183.35.0.0/1883.35.0.1 to 83.35.63.25483.35.63.25516,382
14283.35.64.0/1883.35.64.1 to 83.35.127.25483.35.127.25516,382
14383.35.128.0/1883.35.128.1 to 83.35.191.25483.35.191.25516,382
14483.35.192.0/1883.35.192.1 to 83.35.255.25483.35.255.25516,382
14583.36.0.0/1883.36.0.1 to 83.36.63.25483.36.63.25516,382
14683.36.64.0/1883.36.64.1 to 83.36.127.25483.36.127.25516,382
14783.36.128.0/1883.36.128.1 to 83.36.191.25483.36.191.25516,382
14883.36.192.0/1883.36.192.1 to 83.36.255.25483.36.255.25516,382
14983.37.0.0/1883.37.0.1 to 83.37.63.25483.37.63.25516,382
15083.37.64.0/1883.37.64.1 to 83.37.127.25483.37.127.25516,382
15183.37.128.0/1883.37.128.1 to 83.37.191.25483.37.191.25516,382
15283.37.192.0/1883.37.192.1 to 83.37.255.25483.37.255.25516,382
15383.38.0.0/1883.38.0.1 to 83.38.63.25483.38.63.25516,382
15483.38.64.0/1883.38.64.1 to 83.38.127.25483.38.127.25516,382
15583.38.128.0/1883.38.128.1 to 83.38.191.25483.38.191.25516,382
15683.38.192.0/1883.38.192.1 to 83.38.255.25483.38.255.25516,382
15783.39.0.0/1883.39.0.1 to 83.39.63.25483.39.63.25516,382
15883.39.64.0/1883.39.64.1 to 83.39.127.25483.39.127.25516,382
15983.39.128.0/1883.39.128.1 to 83.39.191.25483.39.191.25516,382
16083.39.192.0/1883.39.192.1 to 83.39.255.25483.39.255.25516,382
16183.40.0.0/1883.40.0.1 to 83.40.63.25483.40.63.25516,382
16283.40.64.0/1883.40.64.1 to 83.40.127.25483.40.127.25516,382
16383.40.128.0/1883.40.128.1 to 83.40.191.25483.40.191.25516,382
16483.40.192.0/1883.40.192.1 to 83.40.255.25483.40.255.25516,382
16583.41.0.0/1883.41.0.1 to 83.41.63.25483.41.63.25516,382
16683.41.64.0/1883.41.64.1 to 83.41.127.25483.41.127.25516,382
16783.41.128.0/1883.41.128.1 to 83.41.191.25483.41.191.25516,382
16883.41.192.0/1883.41.192.1 to 83.41.255.25483.41.255.25516,382
16983.42.0.0/1883.42.0.1 to 83.42.63.25483.42.63.25516,382
17083.42.64.0/1883.42.64.1 to 83.42.127.25483.42.127.25516,382
17183.42.128.0/1883.42.128.1 to 83.42.191.25483.42.191.25516,382
17283.42.192.0/1883.42.192.1 to 83.42.255.25483.42.255.25516,382
17383.43.0.0/1883.43.0.1 to 83.43.63.25483.43.63.25516,382
17483.43.64.0/1883.43.64.1 to 83.43.127.25483.43.127.25516,382
17583.43.128.0/1883.43.128.1 to 83.43.191.25483.43.191.25516,382
17683.43.192.0/1883.43.192.1 to 83.43.255.25483.43.255.25516,382
17783.44.0.0/1883.44.0.1 to 83.44.63.25483.44.63.25516,382
17883.44.64.0/1883.44.64.1 to 83.44.127.25483.44.127.25516,382
17983.44.128.0/1883.44.128.1 to 83.44.191.25483.44.191.25516,382
18083.44.192.0/1883.44.192.1 to 83.44.255.25483.44.255.25516,382
18183.45.0.0/1883.45.0.1 to 83.45.63.25483.45.63.25516,382
18283.45.64.0/1883.45.64.1 to 83.45.127.25483.45.127.25516,382
18383.45.128.0/1883.45.128.1 to 83.45.191.25483.45.191.25516,382
18483.45.192.0/1883.45.192.1 to 83.45.255.25483.45.255.25516,382
18583.46.0.0/1883.46.0.1 to 83.46.63.25483.46.63.25516,382
18683.46.64.0/1883.46.64.1 to 83.46.127.25483.46.127.25516,382
18783.46.128.0/1883.46.128.1 to 83.46.191.25483.46.191.25516,382
18883.46.192.0/1883.46.192.1 to 83.46.255.25483.46.255.25516,382
18983.47.0.0/1883.47.0.1 to 83.47.63.25483.47.63.25516,382
19083.47.64.0/1883.47.64.1 to 83.47.127.25483.47.127.25516,382
19183.47.128.0/1883.47.128.1 to 83.47.191.25483.47.191.25516,382
19283.47.192.0/1883.47.192.1 to 83.47.255.25483.47.255.25516,382
19383.48.0.0/1883.48.0.1 to 83.48.63.25483.48.63.25516,382
19483.48.64.0/1883.48.64.1 to 83.48.127.25483.48.127.25516,382
19583.48.128.0/1883.48.128.1 to 83.48.191.25483.48.191.25516,382
19683.48.192.0/1883.48.192.1 to 83.48.255.25483.48.255.25516,382
19783.49.0.0/1883.49.0.1 to 83.49.63.25483.49.63.25516,382
19883.49.64.0/1883.49.64.1 to 83.49.127.25483.49.127.25516,382
19983.49.128.0/1883.49.128.1 to 83.49.191.25483.49.191.25516,382
20083.49.192.0/1883.49.192.1 to 83.49.255.25483.49.255.25516,382
20183.50.0.0/1883.50.0.1 to 83.50.63.25483.50.63.25516,382
20283.50.64.0/1883.50.64.1 to 83.50.127.25483.50.127.25516,382
20383.50.128.0/1883.50.128.1 to 83.50.191.25483.50.191.25516,382
20483.50.192.0/1883.50.192.1 to 83.50.255.25483.50.255.25516,382
20583.51.0.0/1883.51.0.1 to 83.51.63.25483.51.63.25516,382
20683.51.64.0/1883.51.64.1 to 83.51.127.25483.51.127.25516,382
20783.51.128.0/1883.51.128.1 to 83.51.191.25483.51.191.25516,382
20883.51.192.0/1883.51.192.1 to 83.51.255.25483.51.255.25516,382
20983.52.0.0/1883.52.0.1 to 83.52.63.25483.52.63.25516,382
21083.52.64.0/1883.52.64.1 to 83.52.127.25483.52.127.25516,382
21183.52.128.0/1883.52.128.1 to 83.52.191.25483.52.191.25516,382
21283.52.192.0/1883.52.192.1 to 83.52.255.25483.52.255.25516,382
21383.53.0.0/1883.53.0.1 to 83.53.63.25483.53.63.25516,382
21483.53.64.0/1883.53.64.1 to 83.53.127.25483.53.127.25516,382
21583.53.128.0/1883.53.128.1 to 83.53.191.25483.53.191.25516,382
21683.53.192.0/1883.53.192.1 to 83.53.255.25483.53.255.25516,382
21783.54.0.0/1883.54.0.1 to 83.54.63.25483.54.63.25516,382
21883.54.64.0/1883.54.64.1 to 83.54.127.25483.54.127.25516,382
21983.54.128.0/1883.54.128.1 to 83.54.191.25483.54.191.25516,382
22083.54.192.0/1883.54.192.1 to 83.54.255.25483.54.255.25516,382
22183.55.0.0/1883.55.0.1 to 83.55.63.25483.55.63.25516,382
22283.55.64.0/1883.55.64.1 to 83.55.127.25483.55.127.25516,382
22383.55.128.0/1883.55.128.1 to 83.55.191.25483.55.191.25516,382
22483.55.192.0/1883.55.192.1 to 83.55.255.25483.55.255.25516,382
22583.56.0.0/1883.56.0.1 to 83.56.63.25483.56.63.25516,382
22683.56.64.0/1883.56.64.1 to 83.56.127.25483.56.127.25516,382
22783.56.128.0/1883.56.128.1 to 83.56.191.25483.56.191.25516,382
22883.56.192.0/1883.56.192.1 to 83.56.255.25483.56.255.25516,382
22983.57.0.0/1883.57.0.1 to 83.57.63.25483.57.63.25516,382
23083.57.64.0/1883.57.64.1 to 83.57.127.25483.57.127.25516,382
23183.57.128.0/1883.57.128.1 to 83.57.191.25483.57.191.25516,382
23283.57.192.0/1883.57.192.1 to 83.57.255.25483.57.255.25516,382
23383.58.0.0/1883.58.0.1 to 83.58.63.25483.58.63.25516,382
23483.58.64.0/1883.58.64.1 to 83.58.127.25483.58.127.25516,382
23583.58.128.0/1883.58.128.1 to 83.58.191.25483.58.191.25516,382
23683.58.192.0/1883.58.192.1 to 83.58.255.25483.58.255.25516,382
23783.59.0.0/1883.59.0.1 to 83.59.63.25483.59.63.25516,382
23883.59.64.0/1883.59.64.1 to 83.59.127.25483.59.127.25516,382
23983.59.128.0/1883.59.128.1 to 83.59.191.25483.59.191.25516,382
24083.59.192.0/1883.59.192.1 to 83.59.255.25483.59.255.25516,382
24183.60.0.0/1883.60.0.1 to 83.60.63.25483.60.63.25516,382
24283.60.64.0/1883.60.64.1 to 83.60.127.25483.60.127.25516,382
24383.60.128.0/1883.60.128.1 to 83.60.191.25483.60.191.25516,382
24483.60.192.0/1883.60.192.1 to 83.60.255.25483.60.255.25516,382
24583.61.0.0/1883.61.0.1 to 83.61.63.25483.61.63.25516,382
24683.61.64.0/1883.61.64.1 to 83.61.127.25483.61.127.25516,382
24783.61.128.0/1883.61.128.1 to 83.61.191.25483.61.191.25516,382
24883.61.192.0/1883.61.192.1 to 83.61.255.25483.61.255.25516,382
24983.62.0.0/1883.62.0.1 to 83.62.63.25483.62.63.25516,382
25083.62.64.0/1883.62.64.1 to 83.62.127.25483.62.127.25516,382
25183.62.128.0/1883.62.128.1 to 83.62.191.25483.62.191.25516,382
25283.62.192.0/1883.62.192.1 to 83.62.255.25483.62.255.25516,382
25383.63.0.0/1883.63.0.1 to 83.63.63.25483.63.63.25516,382
25483.63.64.0/1883.63.64.1 to 83.63.127.25483.63.127.25516,382
25583.63.128.0/1883.63.128.1 to 83.63.191.25483.63.191.25516,382
25683.63.192.0/1883.63.192.1 to 83.63.255.25483.63.255.25516,382

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.