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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.

Network24.136.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
24.136.0.0
Broadcast address
24.139.255.255
First usable
24.136.0.1
Last usable
24.139.255.254
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 18880000 · Integer 411566080 to 411828223
Reverse DNS zones
136.24.in-addr.arpa
137.24.in-addr.arpa
138.24.in-addr.arpa
139.24.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
Address00011000.10001000.00000000.0000000024.136.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00011000.10001000.00000000.0000000024.136.0.0
Broadcast00011000.10001011.11111111.1111111124.139.255.255
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)

24.136.0.0/14 makes 4,096 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
124.136.0.0/2624.136.0.1 to 24.136.0.6224.136.0.6362
224.136.0.64/2624.136.0.65 to 24.136.0.12624.136.0.12762
324.136.0.128/2624.136.0.129 to 24.136.0.19024.136.0.19162
424.136.0.192/2624.136.0.193 to 24.136.0.25424.136.0.25562
524.136.1.0/2624.136.1.1 to 24.136.1.6224.136.1.6362
624.136.1.64/2624.136.1.65 to 24.136.1.12624.136.1.12762
724.136.1.128/2624.136.1.129 to 24.136.1.19024.136.1.19162
824.136.1.192/2624.136.1.193 to 24.136.1.25424.136.1.25562
924.136.2.0/2624.136.2.1 to 24.136.2.6224.136.2.6362
1024.136.2.64/2624.136.2.65 to 24.136.2.12624.136.2.12762
1124.136.2.128/2624.136.2.129 to 24.136.2.19024.136.2.19162
1224.136.2.192/2624.136.2.193 to 24.136.2.25424.136.2.25562
1324.136.3.0/2624.136.3.1 to 24.136.3.6224.136.3.6362
1424.136.3.64/2624.136.3.65 to 24.136.3.12624.136.3.12762
1524.136.3.128/2624.136.3.129 to 24.136.3.19024.136.3.19162
1624.136.3.192/2624.136.3.193 to 24.136.3.25424.136.3.25562
1724.136.4.0/2624.136.4.1 to 24.136.4.6224.136.4.6362
1824.136.4.64/2624.136.4.65 to 24.136.4.12624.136.4.12762
1924.136.4.128/2624.136.4.129 to 24.136.4.19024.136.4.19162
2024.136.4.192/2624.136.4.193 to 24.136.4.25424.136.4.25562
2124.136.5.0/2624.136.5.1 to 24.136.5.6224.136.5.6362
2224.136.5.64/2624.136.5.65 to 24.136.5.12624.136.5.12762
2324.136.5.128/2624.136.5.129 to 24.136.5.19024.136.5.19162
2424.136.5.192/2624.136.5.193 to 24.136.5.25424.136.5.25562
2524.136.6.0/2624.136.6.1 to 24.136.6.6224.136.6.6362
2624.136.6.64/2624.136.6.65 to 24.136.6.12624.136.6.12762
2724.136.6.128/2624.136.6.129 to 24.136.6.19024.136.6.19162
2824.136.6.192/2624.136.6.193 to 24.136.6.25424.136.6.25562
2924.136.7.0/2624.136.7.1 to 24.136.7.6224.136.7.6362
3024.136.7.64/2624.136.7.65 to 24.136.7.12624.136.7.12762
3124.136.7.128/2624.136.7.129 to 24.136.7.19024.136.7.19162
3224.136.7.192/2624.136.7.193 to 24.136.7.25424.136.7.25562
3324.136.8.0/2624.136.8.1 to 24.136.8.6224.136.8.6362
3424.136.8.64/2624.136.8.65 to 24.136.8.12624.136.8.12762
3524.136.8.128/2624.136.8.129 to 24.136.8.19024.136.8.19162
3624.136.8.192/2624.136.8.193 to 24.136.8.25424.136.8.25562
3724.136.9.0/2624.136.9.1 to 24.136.9.6224.136.9.6362
3824.136.9.64/2624.136.9.65 to 24.136.9.12624.136.9.12762
3924.136.9.128/2624.136.9.129 to 24.136.9.19024.136.9.19162
4024.136.9.192/2624.136.9.193 to 24.136.9.25424.136.9.25562
4124.136.10.0/2624.136.10.1 to 24.136.10.6224.136.10.6362
4224.136.10.64/2624.136.10.65 to 24.136.10.12624.136.10.12762
4324.136.10.128/2624.136.10.129 to 24.136.10.19024.136.10.19162
4424.136.10.192/2624.136.10.193 to 24.136.10.25424.136.10.25562
4524.136.11.0/2624.136.11.1 to 24.136.11.6224.136.11.6362
4624.136.11.64/2624.136.11.65 to 24.136.11.12624.136.11.12762
4724.136.11.128/2624.136.11.129 to 24.136.11.19024.136.11.19162
4824.136.11.192/2624.136.11.193 to 24.136.11.25424.136.11.25562
4924.136.12.0/2624.136.12.1 to 24.136.12.6224.136.12.6362
5024.136.12.64/2624.136.12.65 to 24.136.12.12624.136.12.12762
5124.136.12.128/2624.136.12.129 to 24.136.12.19024.136.12.19162
5224.136.12.192/2624.136.12.193 to 24.136.12.25424.136.12.25562
5324.136.13.0/2624.136.13.1 to 24.136.13.6224.136.13.6362
5424.136.13.64/2624.136.13.65 to 24.136.13.12624.136.13.12762
5524.136.13.128/2624.136.13.129 to 24.136.13.19024.136.13.19162
5624.136.13.192/2624.136.13.193 to 24.136.13.25424.136.13.25562
5724.136.14.0/2624.136.14.1 to 24.136.14.6224.136.14.6362
5824.136.14.64/2624.136.14.65 to 24.136.14.12624.136.14.12762
5924.136.14.128/2624.136.14.129 to 24.136.14.19024.136.14.19162
6024.136.14.192/2624.136.14.193 to 24.136.14.25424.136.14.25562
6124.136.15.0/2624.136.15.1 to 24.136.15.6224.136.15.6362
6224.136.15.64/2624.136.15.65 to 24.136.15.12624.136.15.12762
6324.136.15.128/2624.136.15.129 to 24.136.15.19024.136.15.19162
6424.136.15.192/2624.136.15.193 to 24.136.15.25424.136.15.25562
6524.136.16.0/2624.136.16.1 to 24.136.16.6224.136.16.6362
6624.136.16.64/2624.136.16.65 to 24.136.16.12624.136.16.12762
6724.136.16.128/2624.136.16.129 to 24.136.16.19024.136.16.19162
6824.136.16.192/2624.136.16.193 to 24.136.16.25424.136.16.25562
6924.136.17.0/2624.136.17.1 to 24.136.17.6224.136.17.6362
7024.136.17.64/2624.136.17.65 to 24.136.17.12624.136.17.12762
7124.136.17.128/2624.136.17.129 to 24.136.17.19024.136.17.19162
7224.136.17.192/2624.136.17.193 to 24.136.17.25424.136.17.25562
7324.136.18.0/2624.136.18.1 to 24.136.18.6224.136.18.6362
7424.136.18.64/2624.136.18.65 to 24.136.18.12624.136.18.12762
7524.136.18.128/2624.136.18.129 to 24.136.18.19024.136.18.19162
7624.136.18.192/2624.136.18.193 to 24.136.18.25424.136.18.25562
7724.136.19.0/2624.136.19.1 to 24.136.19.6224.136.19.6362
7824.136.19.64/2624.136.19.65 to 24.136.19.12624.136.19.12762
7924.136.19.128/2624.136.19.129 to 24.136.19.19024.136.19.19162
8024.136.19.192/2624.136.19.193 to 24.136.19.25424.136.19.25562
8124.136.20.0/2624.136.20.1 to 24.136.20.6224.136.20.6362
8224.136.20.64/2624.136.20.65 to 24.136.20.12624.136.20.12762
8324.136.20.128/2624.136.20.129 to 24.136.20.19024.136.20.19162
8424.136.20.192/2624.136.20.193 to 24.136.20.25424.136.20.25562
8524.136.21.0/2624.136.21.1 to 24.136.21.6224.136.21.6362
8624.136.21.64/2624.136.21.65 to 24.136.21.12624.136.21.12762
8724.136.21.128/2624.136.21.129 to 24.136.21.19024.136.21.19162
8824.136.21.192/2624.136.21.193 to 24.136.21.25424.136.21.25562
8924.136.22.0/2624.136.22.1 to 24.136.22.6224.136.22.6362
9024.136.22.64/2624.136.22.65 to 24.136.22.12624.136.22.12762
9124.136.22.128/2624.136.22.129 to 24.136.22.19024.136.22.19162
9224.136.22.192/2624.136.22.193 to 24.136.22.25424.136.22.25562
9324.136.23.0/2624.136.23.1 to 24.136.23.6224.136.23.6362
9424.136.23.64/2624.136.23.65 to 24.136.23.12624.136.23.12762
9524.136.23.128/2624.136.23.129 to 24.136.23.19024.136.23.19162
9624.136.23.192/2624.136.23.193 to 24.136.23.25424.136.23.25562
9724.136.24.0/2624.136.24.1 to 24.136.24.6224.136.24.6362
9824.136.24.64/2624.136.24.65 to 24.136.24.12624.136.24.12762
9924.136.24.128/2624.136.24.129 to 24.136.24.19024.136.24.19162
10024.136.24.192/2624.136.24.193 to 24.136.24.25424.136.24.25562
10124.136.25.0/2624.136.25.1 to 24.136.25.6224.136.25.6362
10224.136.25.64/2624.136.25.65 to 24.136.25.12624.136.25.12762
10324.136.25.128/2624.136.25.129 to 24.136.25.19024.136.25.19162
10424.136.25.192/2624.136.25.193 to 24.136.25.25424.136.25.25562
10524.136.26.0/2624.136.26.1 to 24.136.26.6224.136.26.6362
10624.136.26.64/2624.136.26.65 to 24.136.26.12624.136.26.12762
10724.136.26.128/2624.136.26.129 to 24.136.26.19024.136.26.19162
10824.136.26.192/2624.136.26.193 to 24.136.26.25424.136.26.25562
10924.136.27.0/2624.136.27.1 to 24.136.27.6224.136.27.6362
11024.136.27.64/2624.136.27.65 to 24.136.27.12624.136.27.12762
11124.136.27.128/2624.136.27.129 to 24.136.27.19024.136.27.19162
11224.136.27.192/2624.136.27.193 to 24.136.27.25424.136.27.25562
11324.136.28.0/2624.136.28.1 to 24.136.28.6224.136.28.6362
11424.136.28.64/2624.136.28.65 to 24.136.28.12624.136.28.12762
11524.136.28.128/2624.136.28.129 to 24.136.28.19024.136.28.19162
11624.136.28.192/2624.136.28.193 to 24.136.28.25424.136.28.25562
11724.136.29.0/2624.136.29.1 to 24.136.29.6224.136.29.6362
11824.136.29.64/2624.136.29.65 to 24.136.29.12624.136.29.12762
11924.136.29.128/2624.136.29.129 to 24.136.29.19024.136.29.19162
12024.136.29.192/2624.136.29.193 to 24.136.29.25424.136.29.25562
12124.136.30.0/2624.136.30.1 to 24.136.30.6224.136.30.6362
12224.136.30.64/2624.136.30.65 to 24.136.30.12624.136.30.12762
12324.136.30.128/2624.136.30.129 to 24.136.30.19024.136.30.19162
12424.136.30.192/2624.136.30.193 to 24.136.30.25424.136.30.25562
12524.136.31.0/2624.136.31.1 to 24.136.31.6224.136.31.6362
12624.136.31.64/2624.136.31.65 to 24.136.31.12624.136.31.12762
12724.136.31.128/2624.136.31.129 to 24.136.31.19024.136.31.19162
12824.136.31.192/2624.136.31.193 to 24.136.31.25424.136.31.25562
12924.136.32.0/2624.136.32.1 to 24.136.32.6224.136.32.6362
13024.136.32.64/2624.136.32.65 to 24.136.32.12624.136.32.12762
13124.136.32.128/2624.136.32.129 to 24.136.32.19024.136.32.19162
13224.136.32.192/2624.136.32.193 to 24.136.32.25424.136.32.25562
13324.136.33.0/2624.136.33.1 to 24.136.33.6224.136.33.6362
13424.136.33.64/2624.136.33.65 to 24.136.33.12624.136.33.12762
13524.136.33.128/2624.136.33.129 to 24.136.33.19024.136.33.19162
13624.136.33.192/2624.136.33.193 to 24.136.33.25424.136.33.25562
13724.136.34.0/2624.136.34.1 to 24.136.34.6224.136.34.6362
13824.136.34.64/2624.136.34.65 to 24.136.34.12624.136.34.12762
13924.136.34.128/2624.136.34.129 to 24.136.34.19024.136.34.19162
14024.136.34.192/2624.136.34.193 to 24.136.34.25424.136.34.25562
14124.136.35.0/2624.136.35.1 to 24.136.35.6224.136.35.6362
14224.136.35.64/2624.136.35.65 to 24.136.35.12624.136.35.12762
14324.136.35.128/2624.136.35.129 to 24.136.35.19024.136.35.19162
14424.136.35.192/2624.136.35.193 to 24.136.35.25424.136.35.25562
14524.136.36.0/2624.136.36.1 to 24.136.36.6224.136.36.6362
14624.136.36.64/2624.136.36.65 to 24.136.36.12624.136.36.12762
14724.136.36.128/2624.136.36.129 to 24.136.36.19024.136.36.19162
14824.136.36.192/2624.136.36.193 to 24.136.36.25424.136.36.25562
14924.136.37.0/2624.136.37.1 to 24.136.37.6224.136.37.6362
15024.136.37.64/2624.136.37.65 to 24.136.37.12624.136.37.12762
15124.136.37.128/2624.136.37.129 to 24.136.37.19024.136.37.19162
15224.136.37.192/2624.136.37.193 to 24.136.37.25424.136.37.25562
15324.136.38.0/2624.136.38.1 to 24.136.38.6224.136.38.6362
15424.136.38.64/2624.136.38.65 to 24.136.38.12624.136.38.12762
15524.136.38.128/2624.136.38.129 to 24.136.38.19024.136.38.19162
15624.136.38.192/2624.136.38.193 to 24.136.38.25424.136.38.25562
15724.136.39.0/2624.136.39.1 to 24.136.39.6224.136.39.6362
15824.136.39.64/2624.136.39.65 to 24.136.39.12624.136.39.12762
15924.136.39.128/2624.136.39.129 to 24.136.39.19024.136.39.19162
16024.136.39.192/2624.136.39.193 to 24.136.39.25424.136.39.25562
16124.136.40.0/2624.136.40.1 to 24.136.40.6224.136.40.6362
16224.136.40.64/2624.136.40.65 to 24.136.40.12624.136.40.12762
16324.136.40.128/2624.136.40.129 to 24.136.40.19024.136.40.19162
16424.136.40.192/2624.136.40.193 to 24.136.40.25424.136.40.25562
16524.136.41.0/2624.136.41.1 to 24.136.41.6224.136.41.6362
16624.136.41.64/2624.136.41.65 to 24.136.41.12624.136.41.12762
16724.136.41.128/2624.136.41.129 to 24.136.41.19024.136.41.19162
16824.136.41.192/2624.136.41.193 to 24.136.41.25424.136.41.25562
16924.136.42.0/2624.136.42.1 to 24.136.42.6224.136.42.6362
17024.136.42.64/2624.136.42.65 to 24.136.42.12624.136.42.12762
17124.136.42.128/2624.136.42.129 to 24.136.42.19024.136.42.19162
17224.136.42.192/2624.136.42.193 to 24.136.42.25424.136.42.25562
17324.136.43.0/2624.136.43.1 to 24.136.43.6224.136.43.6362
17424.136.43.64/2624.136.43.65 to 24.136.43.12624.136.43.12762
17524.136.43.128/2624.136.43.129 to 24.136.43.19024.136.43.19162
17624.136.43.192/2624.136.43.193 to 24.136.43.25424.136.43.25562
17724.136.44.0/2624.136.44.1 to 24.136.44.6224.136.44.6362
17824.136.44.64/2624.136.44.65 to 24.136.44.12624.136.44.12762
17924.136.44.128/2624.136.44.129 to 24.136.44.19024.136.44.19162
18024.136.44.192/2624.136.44.193 to 24.136.44.25424.136.44.25562
18124.136.45.0/2624.136.45.1 to 24.136.45.6224.136.45.6362
18224.136.45.64/2624.136.45.65 to 24.136.45.12624.136.45.12762
18324.136.45.128/2624.136.45.129 to 24.136.45.19024.136.45.19162
18424.136.45.192/2624.136.45.193 to 24.136.45.25424.136.45.25562
18524.136.46.0/2624.136.46.1 to 24.136.46.6224.136.46.6362
18624.136.46.64/2624.136.46.65 to 24.136.46.12624.136.46.12762
18724.136.46.128/2624.136.46.129 to 24.136.46.19024.136.46.19162
18824.136.46.192/2624.136.46.193 to 24.136.46.25424.136.46.25562
18924.136.47.0/2624.136.47.1 to 24.136.47.6224.136.47.6362
19024.136.47.64/2624.136.47.65 to 24.136.47.12624.136.47.12762
19124.136.47.128/2624.136.47.129 to 24.136.47.19024.136.47.19162
19224.136.47.192/2624.136.47.193 to 24.136.47.25424.136.47.25562
19324.136.48.0/2624.136.48.1 to 24.136.48.6224.136.48.6362
19424.136.48.64/2624.136.48.65 to 24.136.48.12624.136.48.12762
19524.136.48.128/2624.136.48.129 to 24.136.48.19024.136.48.19162
19624.136.48.192/2624.136.48.193 to 24.136.48.25424.136.48.25562
19724.136.49.0/2624.136.49.1 to 24.136.49.6224.136.49.6362
19824.136.49.64/2624.136.49.65 to 24.136.49.12624.136.49.12762
19924.136.49.128/2624.136.49.129 to 24.136.49.19024.136.49.19162
20024.136.49.192/2624.136.49.193 to 24.136.49.25424.136.49.25562
20124.136.50.0/2624.136.50.1 to 24.136.50.6224.136.50.6362
20224.136.50.64/2624.136.50.65 to 24.136.50.12624.136.50.12762
20324.136.50.128/2624.136.50.129 to 24.136.50.19024.136.50.19162
20424.136.50.192/2624.136.50.193 to 24.136.50.25424.136.50.25562
20524.136.51.0/2624.136.51.1 to 24.136.51.6224.136.51.6362
20624.136.51.64/2624.136.51.65 to 24.136.51.12624.136.51.12762
20724.136.51.128/2624.136.51.129 to 24.136.51.19024.136.51.19162
20824.136.51.192/2624.136.51.193 to 24.136.51.25424.136.51.25562
20924.136.52.0/2624.136.52.1 to 24.136.52.6224.136.52.6362
21024.136.52.64/2624.136.52.65 to 24.136.52.12624.136.52.12762
21124.136.52.128/2624.136.52.129 to 24.136.52.19024.136.52.19162
21224.136.52.192/2624.136.52.193 to 24.136.52.25424.136.52.25562
21324.136.53.0/2624.136.53.1 to 24.136.53.6224.136.53.6362
21424.136.53.64/2624.136.53.65 to 24.136.53.12624.136.53.12762
21524.136.53.128/2624.136.53.129 to 24.136.53.19024.136.53.19162
21624.136.53.192/2624.136.53.193 to 24.136.53.25424.136.53.25562
21724.136.54.0/2624.136.54.1 to 24.136.54.6224.136.54.6362
21824.136.54.64/2624.136.54.65 to 24.136.54.12624.136.54.12762
21924.136.54.128/2624.136.54.129 to 24.136.54.19024.136.54.19162
22024.136.54.192/2624.136.54.193 to 24.136.54.25424.136.54.25562
22124.136.55.0/2624.136.55.1 to 24.136.55.6224.136.55.6362
22224.136.55.64/2624.136.55.65 to 24.136.55.12624.136.55.12762
22324.136.55.128/2624.136.55.129 to 24.136.55.19024.136.55.19162
22424.136.55.192/2624.136.55.193 to 24.136.55.25424.136.55.25562
22524.136.56.0/2624.136.56.1 to 24.136.56.6224.136.56.6362
22624.136.56.64/2624.136.56.65 to 24.136.56.12624.136.56.12762
22724.136.56.128/2624.136.56.129 to 24.136.56.19024.136.56.19162
22824.136.56.192/2624.136.56.193 to 24.136.56.25424.136.56.25562
22924.136.57.0/2624.136.57.1 to 24.136.57.6224.136.57.6362
23024.136.57.64/2624.136.57.65 to 24.136.57.12624.136.57.12762
23124.136.57.128/2624.136.57.129 to 24.136.57.19024.136.57.19162
23224.136.57.192/2624.136.57.193 to 24.136.57.25424.136.57.25562
23324.136.58.0/2624.136.58.1 to 24.136.58.6224.136.58.6362
23424.136.58.64/2624.136.58.65 to 24.136.58.12624.136.58.12762
23524.136.58.128/2624.136.58.129 to 24.136.58.19024.136.58.19162
23624.136.58.192/2624.136.58.193 to 24.136.58.25424.136.58.25562
23724.136.59.0/2624.136.59.1 to 24.136.59.6224.136.59.6362
23824.136.59.64/2624.136.59.65 to 24.136.59.12624.136.59.12762
23924.136.59.128/2624.136.59.129 to 24.136.59.19024.136.59.19162
24024.136.59.192/2624.136.59.193 to 24.136.59.25424.136.59.25562
24124.136.60.0/2624.136.60.1 to 24.136.60.6224.136.60.6362
24224.136.60.64/2624.136.60.65 to 24.136.60.12624.136.60.12762
24324.136.60.128/2624.136.60.129 to 24.136.60.19024.136.60.19162
24424.136.60.192/2624.136.60.193 to 24.136.60.25424.136.60.25562
24524.136.61.0/2624.136.61.1 to 24.136.61.6224.136.61.6362
24624.136.61.64/2624.136.61.65 to 24.136.61.12624.136.61.12762
24724.136.61.128/2624.136.61.129 to 24.136.61.19024.136.61.19162
24824.136.61.192/2624.136.61.193 to 24.136.61.25424.136.61.25562
24924.136.62.0/2624.136.62.1 to 24.136.62.6224.136.62.6362
25024.136.62.64/2624.136.62.65 to 24.136.62.12624.136.62.12762
25124.136.62.128/2624.136.62.129 to 24.136.62.19024.136.62.19162
25224.136.62.192/2624.136.62.193 to 24.136.62.25424.136.62.25562
25324.136.63.0/2624.136.63.1 to 24.136.63.6224.136.63.6362
25424.136.63.64/2624.136.63.65 to 24.136.63.12624.136.63.12762
25524.136.63.128/2624.136.63.129 to 24.136.63.19024.136.63.19162
25624.136.63.192/2624.136.63.193 to 24.136.63.25424.136.63.25562

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.