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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.

Network97.232.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
97.232.0.0
Broadcast address
97.235.255.255
First usable
97.232.0.1
Last usable
97.235.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
A (default /8)
As numbers
Hex 61E80000 · Integer 1642594304 to 1642856447
Reverse DNS zones
232.97.in-addr.arpa
233.97.in-addr.arpa
234.97.in-addr.arpa
235.97.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01100001.11101000.00000000.0000000097.232.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01100001.11101000.00000000.0000000097.232.0.0
Broadcast01100001.11101011.11111111.1111111197.235.255.255
Split into smaller subnets/26
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

97.232.0.0/14 makes 4,096 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
197.232.0.0/2697.232.0.1 to 97.232.0.6297.232.0.6362
297.232.0.64/2697.232.0.65 to 97.232.0.12697.232.0.12762
397.232.0.128/2697.232.0.129 to 97.232.0.19097.232.0.19162
497.232.0.192/2697.232.0.193 to 97.232.0.25497.232.0.25562
597.232.1.0/2697.232.1.1 to 97.232.1.6297.232.1.6362
697.232.1.64/2697.232.1.65 to 97.232.1.12697.232.1.12762
797.232.1.128/2697.232.1.129 to 97.232.1.19097.232.1.19162
897.232.1.192/2697.232.1.193 to 97.232.1.25497.232.1.25562
997.232.2.0/2697.232.2.1 to 97.232.2.6297.232.2.6362
1097.232.2.64/2697.232.2.65 to 97.232.2.12697.232.2.12762
1197.232.2.128/2697.232.2.129 to 97.232.2.19097.232.2.19162
1297.232.2.192/2697.232.2.193 to 97.232.2.25497.232.2.25562
1397.232.3.0/2697.232.3.1 to 97.232.3.6297.232.3.6362
1497.232.3.64/2697.232.3.65 to 97.232.3.12697.232.3.12762
1597.232.3.128/2697.232.3.129 to 97.232.3.19097.232.3.19162
1697.232.3.192/2697.232.3.193 to 97.232.3.25497.232.3.25562
1797.232.4.0/2697.232.4.1 to 97.232.4.6297.232.4.6362
1897.232.4.64/2697.232.4.65 to 97.232.4.12697.232.4.12762
1997.232.4.128/2697.232.4.129 to 97.232.4.19097.232.4.19162
2097.232.4.192/2697.232.4.193 to 97.232.4.25497.232.4.25562
2197.232.5.0/2697.232.5.1 to 97.232.5.6297.232.5.6362
2297.232.5.64/2697.232.5.65 to 97.232.5.12697.232.5.12762
2397.232.5.128/2697.232.5.129 to 97.232.5.19097.232.5.19162
2497.232.5.192/2697.232.5.193 to 97.232.5.25497.232.5.25562
2597.232.6.0/2697.232.6.1 to 97.232.6.6297.232.6.6362
2697.232.6.64/2697.232.6.65 to 97.232.6.12697.232.6.12762
2797.232.6.128/2697.232.6.129 to 97.232.6.19097.232.6.19162
2897.232.6.192/2697.232.6.193 to 97.232.6.25497.232.6.25562
2997.232.7.0/2697.232.7.1 to 97.232.7.6297.232.7.6362
3097.232.7.64/2697.232.7.65 to 97.232.7.12697.232.7.12762
3197.232.7.128/2697.232.7.129 to 97.232.7.19097.232.7.19162
3297.232.7.192/2697.232.7.193 to 97.232.7.25497.232.7.25562
3397.232.8.0/2697.232.8.1 to 97.232.8.6297.232.8.6362
3497.232.8.64/2697.232.8.65 to 97.232.8.12697.232.8.12762
3597.232.8.128/2697.232.8.129 to 97.232.8.19097.232.8.19162
3697.232.8.192/2697.232.8.193 to 97.232.8.25497.232.8.25562
3797.232.9.0/2697.232.9.1 to 97.232.9.6297.232.9.6362
3897.232.9.64/2697.232.9.65 to 97.232.9.12697.232.9.12762
3997.232.9.128/2697.232.9.129 to 97.232.9.19097.232.9.19162
4097.232.9.192/2697.232.9.193 to 97.232.9.25497.232.9.25562
4197.232.10.0/2697.232.10.1 to 97.232.10.6297.232.10.6362
4297.232.10.64/2697.232.10.65 to 97.232.10.12697.232.10.12762
4397.232.10.128/2697.232.10.129 to 97.232.10.19097.232.10.19162
4497.232.10.192/2697.232.10.193 to 97.232.10.25497.232.10.25562
4597.232.11.0/2697.232.11.1 to 97.232.11.6297.232.11.6362
4697.232.11.64/2697.232.11.65 to 97.232.11.12697.232.11.12762
4797.232.11.128/2697.232.11.129 to 97.232.11.19097.232.11.19162
4897.232.11.192/2697.232.11.193 to 97.232.11.25497.232.11.25562
4997.232.12.0/2697.232.12.1 to 97.232.12.6297.232.12.6362
5097.232.12.64/2697.232.12.65 to 97.232.12.12697.232.12.12762
5197.232.12.128/2697.232.12.129 to 97.232.12.19097.232.12.19162
5297.232.12.192/2697.232.12.193 to 97.232.12.25497.232.12.25562
5397.232.13.0/2697.232.13.1 to 97.232.13.6297.232.13.6362
5497.232.13.64/2697.232.13.65 to 97.232.13.12697.232.13.12762
5597.232.13.128/2697.232.13.129 to 97.232.13.19097.232.13.19162
5697.232.13.192/2697.232.13.193 to 97.232.13.25497.232.13.25562
5797.232.14.0/2697.232.14.1 to 97.232.14.6297.232.14.6362
5897.232.14.64/2697.232.14.65 to 97.232.14.12697.232.14.12762
5997.232.14.128/2697.232.14.129 to 97.232.14.19097.232.14.19162
6097.232.14.192/2697.232.14.193 to 97.232.14.25497.232.14.25562
6197.232.15.0/2697.232.15.1 to 97.232.15.6297.232.15.6362
6297.232.15.64/2697.232.15.65 to 97.232.15.12697.232.15.12762
6397.232.15.128/2697.232.15.129 to 97.232.15.19097.232.15.19162
6497.232.15.192/2697.232.15.193 to 97.232.15.25497.232.15.25562
6597.232.16.0/2697.232.16.1 to 97.232.16.6297.232.16.6362
6697.232.16.64/2697.232.16.65 to 97.232.16.12697.232.16.12762
6797.232.16.128/2697.232.16.129 to 97.232.16.19097.232.16.19162
6897.232.16.192/2697.232.16.193 to 97.232.16.25497.232.16.25562
6997.232.17.0/2697.232.17.1 to 97.232.17.6297.232.17.6362
7097.232.17.64/2697.232.17.65 to 97.232.17.12697.232.17.12762
7197.232.17.128/2697.232.17.129 to 97.232.17.19097.232.17.19162
7297.232.17.192/2697.232.17.193 to 97.232.17.25497.232.17.25562
7397.232.18.0/2697.232.18.1 to 97.232.18.6297.232.18.6362
7497.232.18.64/2697.232.18.65 to 97.232.18.12697.232.18.12762
7597.232.18.128/2697.232.18.129 to 97.232.18.19097.232.18.19162
7697.232.18.192/2697.232.18.193 to 97.232.18.25497.232.18.25562
7797.232.19.0/2697.232.19.1 to 97.232.19.6297.232.19.6362
7897.232.19.64/2697.232.19.65 to 97.232.19.12697.232.19.12762
7997.232.19.128/2697.232.19.129 to 97.232.19.19097.232.19.19162
8097.232.19.192/2697.232.19.193 to 97.232.19.25497.232.19.25562
8197.232.20.0/2697.232.20.1 to 97.232.20.6297.232.20.6362
8297.232.20.64/2697.232.20.65 to 97.232.20.12697.232.20.12762
8397.232.20.128/2697.232.20.129 to 97.232.20.19097.232.20.19162
8497.232.20.192/2697.232.20.193 to 97.232.20.25497.232.20.25562
8597.232.21.0/2697.232.21.1 to 97.232.21.6297.232.21.6362
8697.232.21.64/2697.232.21.65 to 97.232.21.12697.232.21.12762
8797.232.21.128/2697.232.21.129 to 97.232.21.19097.232.21.19162
8897.232.21.192/2697.232.21.193 to 97.232.21.25497.232.21.25562
8997.232.22.0/2697.232.22.1 to 97.232.22.6297.232.22.6362
9097.232.22.64/2697.232.22.65 to 97.232.22.12697.232.22.12762
9197.232.22.128/2697.232.22.129 to 97.232.22.19097.232.22.19162
9297.232.22.192/2697.232.22.193 to 97.232.22.25497.232.22.25562
9397.232.23.0/2697.232.23.1 to 97.232.23.6297.232.23.6362
9497.232.23.64/2697.232.23.65 to 97.232.23.12697.232.23.12762
9597.232.23.128/2697.232.23.129 to 97.232.23.19097.232.23.19162
9697.232.23.192/2697.232.23.193 to 97.232.23.25497.232.23.25562
9797.232.24.0/2697.232.24.1 to 97.232.24.6297.232.24.6362
9897.232.24.64/2697.232.24.65 to 97.232.24.12697.232.24.12762
9997.232.24.128/2697.232.24.129 to 97.232.24.19097.232.24.19162
10097.232.24.192/2697.232.24.193 to 97.232.24.25497.232.24.25562
10197.232.25.0/2697.232.25.1 to 97.232.25.6297.232.25.6362
10297.232.25.64/2697.232.25.65 to 97.232.25.12697.232.25.12762
10397.232.25.128/2697.232.25.129 to 97.232.25.19097.232.25.19162
10497.232.25.192/2697.232.25.193 to 97.232.25.25497.232.25.25562
10597.232.26.0/2697.232.26.1 to 97.232.26.6297.232.26.6362
10697.232.26.64/2697.232.26.65 to 97.232.26.12697.232.26.12762
10797.232.26.128/2697.232.26.129 to 97.232.26.19097.232.26.19162
10897.232.26.192/2697.232.26.193 to 97.232.26.25497.232.26.25562
10997.232.27.0/2697.232.27.1 to 97.232.27.6297.232.27.6362
11097.232.27.64/2697.232.27.65 to 97.232.27.12697.232.27.12762
11197.232.27.128/2697.232.27.129 to 97.232.27.19097.232.27.19162
11297.232.27.192/2697.232.27.193 to 97.232.27.25497.232.27.25562
11397.232.28.0/2697.232.28.1 to 97.232.28.6297.232.28.6362
11497.232.28.64/2697.232.28.65 to 97.232.28.12697.232.28.12762
11597.232.28.128/2697.232.28.129 to 97.232.28.19097.232.28.19162
11697.232.28.192/2697.232.28.193 to 97.232.28.25497.232.28.25562
11797.232.29.0/2697.232.29.1 to 97.232.29.6297.232.29.6362
11897.232.29.64/2697.232.29.65 to 97.232.29.12697.232.29.12762
11997.232.29.128/2697.232.29.129 to 97.232.29.19097.232.29.19162
12097.232.29.192/2697.232.29.193 to 97.232.29.25497.232.29.25562
12197.232.30.0/2697.232.30.1 to 97.232.30.6297.232.30.6362
12297.232.30.64/2697.232.30.65 to 97.232.30.12697.232.30.12762
12397.232.30.128/2697.232.30.129 to 97.232.30.19097.232.30.19162
12497.232.30.192/2697.232.30.193 to 97.232.30.25497.232.30.25562
12597.232.31.0/2697.232.31.1 to 97.232.31.6297.232.31.6362
12697.232.31.64/2697.232.31.65 to 97.232.31.12697.232.31.12762
12797.232.31.128/2697.232.31.129 to 97.232.31.19097.232.31.19162
12897.232.31.192/2697.232.31.193 to 97.232.31.25497.232.31.25562
12997.232.32.0/2697.232.32.1 to 97.232.32.6297.232.32.6362
13097.232.32.64/2697.232.32.65 to 97.232.32.12697.232.32.12762
13197.232.32.128/2697.232.32.129 to 97.232.32.19097.232.32.19162
13297.232.32.192/2697.232.32.193 to 97.232.32.25497.232.32.25562
13397.232.33.0/2697.232.33.1 to 97.232.33.6297.232.33.6362
13497.232.33.64/2697.232.33.65 to 97.232.33.12697.232.33.12762
13597.232.33.128/2697.232.33.129 to 97.232.33.19097.232.33.19162
13697.232.33.192/2697.232.33.193 to 97.232.33.25497.232.33.25562
13797.232.34.0/2697.232.34.1 to 97.232.34.6297.232.34.6362
13897.232.34.64/2697.232.34.65 to 97.232.34.12697.232.34.12762
13997.232.34.128/2697.232.34.129 to 97.232.34.19097.232.34.19162
14097.232.34.192/2697.232.34.193 to 97.232.34.25497.232.34.25562
14197.232.35.0/2697.232.35.1 to 97.232.35.6297.232.35.6362
14297.232.35.64/2697.232.35.65 to 97.232.35.12697.232.35.12762
14397.232.35.128/2697.232.35.129 to 97.232.35.19097.232.35.19162
14497.232.35.192/2697.232.35.193 to 97.232.35.25497.232.35.25562
14597.232.36.0/2697.232.36.1 to 97.232.36.6297.232.36.6362
14697.232.36.64/2697.232.36.65 to 97.232.36.12697.232.36.12762
14797.232.36.128/2697.232.36.129 to 97.232.36.19097.232.36.19162
14897.232.36.192/2697.232.36.193 to 97.232.36.25497.232.36.25562
14997.232.37.0/2697.232.37.1 to 97.232.37.6297.232.37.6362
15097.232.37.64/2697.232.37.65 to 97.232.37.12697.232.37.12762
15197.232.37.128/2697.232.37.129 to 97.232.37.19097.232.37.19162
15297.232.37.192/2697.232.37.193 to 97.232.37.25497.232.37.25562
15397.232.38.0/2697.232.38.1 to 97.232.38.6297.232.38.6362
15497.232.38.64/2697.232.38.65 to 97.232.38.12697.232.38.12762
15597.232.38.128/2697.232.38.129 to 97.232.38.19097.232.38.19162
15697.232.38.192/2697.232.38.193 to 97.232.38.25497.232.38.25562
15797.232.39.0/2697.232.39.1 to 97.232.39.6297.232.39.6362
15897.232.39.64/2697.232.39.65 to 97.232.39.12697.232.39.12762
15997.232.39.128/2697.232.39.129 to 97.232.39.19097.232.39.19162
16097.232.39.192/2697.232.39.193 to 97.232.39.25497.232.39.25562
16197.232.40.0/2697.232.40.1 to 97.232.40.6297.232.40.6362
16297.232.40.64/2697.232.40.65 to 97.232.40.12697.232.40.12762
16397.232.40.128/2697.232.40.129 to 97.232.40.19097.232.40.19162
16497.232.40.192/2697.232.40.193 to 97.232.40.25497.232.40.25562
16597.232.41.0/2697.232.41.1 to 97.232.41.6297.232.41.6362
16697.232.41.64/2697.232.41.65 to 97.232.41.12697.232.41.12762
16797.232.41.128/2697.232.41.129 to 97.232.41.19097.232.41.19162
16897.232.41.192/2697.232.41.193 to 97.232.41.25497.232.41.25562
16997.232.42.0/2697.232.42.1 to 97.232.42.6297.232.42.6362
17097.232.42.64/2697.232.42.65 to 97.232.42.12697.232.42.12762
17197.232.42.128/2697.232.42.129 to 97.232.42.19097.232.42.19162
17297.232.42.192/2697.232.42.193 to 97.232.42.25497.232.42.25562
17397.232.43.0/2697.232.43.1 to 97.232.43.6297.232.43.6362
17497.232.43.64/2697.232.43.65 to 97.232.43.12697.232.43.12762
17597.232.43.128/2697.232.43.129 to 97.232.43.19097.232.43.19162
17697.232.43.192/2697.232.43.193 to 97.232.43.25497.232.43.25562
17797.232.44.0/2697.232.44.1 to 97.232.44.6297.232.44.6362
17897.232.44.64/2697.232.44.65 to 97.232.44.12697.232.44.12762
17997.232.44.128/2697.232.44.129 to 97.232.44.19097.232.44.19162
18097.232.44.192/2697.232.44.193 to 97.232.44.25497.232.44.25562
18197.232.45.0/2697.232.45.1 to 97.232.45.6297.232.45.6362
18297.232.45.64/2697.232.45.65 to 97.232.45.12697.232.45.12762
18397.232.45.128/2697.232.45.129 to 97.232.45.19097.232.45.19162
18497.232.45.192/2697.232.45.193 to 97.232.45.25497.232.45.25562
18597.232.46.0/2697.232.46.1 to 97.232.46.6297.232.46.6362
18697.232.46.64/2697.232.46.65 to 97.232.46.12697.232.46.12762
18797.232.46.128/2697.232.46.129 to 97.232.46.19097.232.46.19162
18897.232.46.192/2697.232.46.193 to 97.232.46.25497.232.46.25562
18997.232.47.0/2697.232.47.1 to 97.232.47.6297.232.47.6362
19097.232.47.64/2697.232.47.65 to 97.232.47.12697.232.47.12762
19197.232.47.128/2697.232.47.129 to 97.232.47.19097.232.47.19162
19297.232.47.192/2697.232.47.193 to 97.232.47.25497.232.47.25562
19397.232.48.0/2697.232.48.1 to 97.232.48.6297.232.48.6362
19497.232.48.64/2697.232.48.65 to 97.232.48.12697.232.48.12762
19597.232.48.128/2697.232.48.129 to 97.232.48.19097.232.48.19162
19697.232.48.192/2697.232.48.193 to 97.232.48.25497.232.48.25562
19797.232.49.0/2697.232.49.1 to 97.232.49.6297.232.49.6362
19897.232.49.64/2697.232.49.65 to 97.232.49.12697.232.49.12762
19997.232.49.128/2697.232.49.129 to 97.232.49.19097.232.49.19162
20097.232.49.192/2697.232.49.193 to 97.232.49.25497.232.49.25562
20197.232.50.0/2697.232.50.1 to 97.232.50.6297.232.50.6362
20297.232.50.64/2697.232.50.65 to 97.232.50.12697.232.50.12762
20397.232.50.128/2697.232.50.129 to 97.232.50.19097.232.50.19162
20497.232.50.192/2697.232.50.193 to 97.232.50.25497.232.50.25562
20597.232.51.0/2697.232.51.1 to 97.232.51.6297.232.51.6362
20697.232.51.64/2697.232.51.65 to 97.232.51.12697.232.51.12762
20797.232.51.128/2697.232.51.129 to 97.232.51.19097.232.51.19162
20897.232.51.192/2697.232.51.193 to 97.232.51.25497.232.51.25562
20997.232.52.0/2697.232.52.1 to 97.232.52.6297.232.52.6362
21097.232.52.64/2697.232.52.65 to 97.232.52.12697.232.52.12762
21197.232.52.128/2697.232.52.129 to 97.232.52.19097.232.52.19162
21297.232.52.192/2697.232.52.193 to 97.232.52.25497.232.52.25562
21397.232.53.0/2697.232.53.1 to 97.232.53.6297.232.53.6362
21497.232.53.64/2697.232.53.65 to 97.232.53.12697.232.53.12762
21597.232.53.128/2697.232.53.129 to 97.232.53.19097.232.53.19162
21697.232.53.192/2697.232.53.193 to 97.232.53.25497.232.53.25562
21797.232.54.0/2697.232.54.1 to 97.232.54.6297.232.54.6362
21897.232.54.64/2697.232.54.65 to 97.232.54.12697.232.54.12762
21997.232.54.128/2697.232.54.129 to 97.232.54.19097.232.54.19162
22097.232.54.192/2697.232.54.193 to 97.232.54.25497.232.54.25562
22197.232.55.0/2697.232.55.1 to 97.232.55.6297.232.55.6362
22297.232.55.64/2697.232.55.65 to 97.232.55.12697.232.55.12762
22397.232.55.128/2697.232.55.129 to 97.232.55.19097.232.55.19162
22497.232.55.192/2697.232.55.193 to 97.232.55.25497.232.55.25562
22597.232.56.0/2697.232.56.1 to 97.232.56.6297.232.56.6362
22697.232.56.64/2697.232.56.65 to 97.232.56.12697.232.56.12762
22797.232.56.128/2697.232.56.129 to 97.232.56.19097.232.56.19162
22897.232.56.192/2697.232.56.193 to 97.232.56.25497.232.56.25562
22997.232.57.0/2697.232.57.1 to 97.232.57.6297.232.57.6362
23097.232.57.64/2697.232.57.65 to 97.232.57.12697.232.57.12762
23197.232.57.128/2697.232.57.129 to 97.232.57.19097.232.57.19162
23297.232.57.192/2697.232.57.193 to 97.232.57.25497.232.57.25562
23397.232.58.0/2697.232.58.1 to 97.232.58.6297.232.58.6362
23497.232.58.64/2697.232.58.65 to 97.232.58.12697.232.58.12762
23597.232.58.128/2697.232.58.129 to 97.232.58.19097.232.58.19162
23697.232.58.192/2697.232.58.193 to 97.232.58.25497.232.58.25562
23797.232.59.0/2697.232.59.1 to 97.232.59.6297.232.59.6362
23897.232.59.64/2697.232.59.65 to 97.232.59.12697.232.59.12762
23997.232.59.128/2697.232.59.129 to 97.232.59.19097.232.59.19162
24097.232.59.192/2697.232.59.193 to 97.232.59.25497.232.59.25562
24197.232.60.0/2697.232.60.1 to 97.232.60.6297.232.60.6362
24297.232.60.64/2697.232.60.65 to 97.232.60.12697.232.60.12762
24397.232.60.128/2697.232.60.129 to 97.232.60.19097.232.60.19162
24497.232.60.192/2697.232.60.193 to 97.232.60.25497.232.60.25562
24597.232.61.0/2697.232.61.1 to 97.232.61.6297.232.61.6362
24697.232.61.64/2697.232.61.65 to 97.232.61.12697.232.61.12762
24797.232.61.128/2697.232.61.129 to 97.232.61.19097.232.61.19162
24897.232.61.192/2697.232.61.193 to 97.232.61.25497.232.61.25562
24997.232.62.0/2697.232.62.1 to 97.232.62.6297.232.62.6362
25097.232.62.64/2697.232.62.65 to 97.232.62.12697.232.62.12762
25197.232.62.128/2697.232.62.129 to 97.232.62.19097.232.62.19162
25297.232.62.192/2697.232.62.193 to 97.232.62.25497.232.62.25562
25397.232.63.0/2697.232.63.1 to 97.232.63.6297.232.63.6362
25497.232.63.64/2697.232.63.65 to 97.232.63.12697.232.63.12762
25597.232.63.128/2697.232.63.129 to 97.232.63.19097.232.63.19162
25697.232.63.192/2697.232.63.193 to 97.232.63.25497.232.63.25562

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

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.