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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.

Network17.76.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
17.76.0.0
Broadcast address
17.79.255.255
First usable
17.76.0.1
Last usable
17.79.255.254
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 114C0000 · Integer 290193408 to 290455551
Reverse DNS zones
76.17.in-addr.arpa
77.17.in-addr.arpa
78.17.in-addr.arpa
79.17.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
Address00010001.01001100.00000000.0000000017.76.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00010001.01001100.00000000.0000000017.76.0.0
Broadcast00010001.01001111.11111111.1111111117.79.255.255
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)

17.76.0.0/14 makes 4,096 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
117.76.0.0/2617.76.0.1 to 17.76.0.6217.76.0.6362
217.76.0.64/2617.76.0.65 to 17.76.0.12617.76.0.12762
317.76.0.128/2617.76.0.129 to 17.76.0.19017.76.0.19162
417.76.0.192/2617.76.0.193 to 17.76.0.25417.76.0.25562
517.76.1.0/2617.76.1.1 to 17.76.1.6217.76.1.6362
617.76.1.64/2617.76.1.65 to 17.76.1.12617.76.1.12762
717.76.1.128/2617.76.1.129 to 17.76.1.19017.76.1.19162
817.76.1.192/2617.76.1.193 to 17.76.1.25417.76.1.25562
917.76.2.0/2617.76.2.1 to 17.76.2.6217.76.2.6362
1017.76.2.64/2617.76.2.65 to 17.76.2.12617.76.2.12762
1117.76.2.128/2617.76.2.129 to 17.76.2.19017.76.2.19162
1217.76.2.192/2617.76.2.193 to 17.76.2.25417.76.2.25562
1317.76.3.0/2617.76.3.1 to 17.76.3.6217.76.3.6362
1417.76.3.64/2617.76.3.65 to 17.76.3.12617.76.3.12762
1517.76.3.128/2617.76.3.129 to 17.76.3.19017.76.3.19162
1617.76.3.192/2617.76.3.193 to 17.76.3.25417.76.3.25562
1717.76.4.0/2617.76.4.1 to 17.76.4.6217.76.4.6362
1817.76.4.64/2617.76.4.65 to 17.76.4.12617.76.4.12762
1917.76.4.128/2617.76.4.129 to 17.76.4.19017.76.4.19162
2017.76.4.192/2617.76.4.193 to 17.76.4.25417.76.4.25562
2117.76.5.0/2617.76.5.1 to 17.76.5.6217.76.5.6362
2217.76.5.64/2617.76.5.65 to 17.76.5.12617.76.5.12762
2317.76.5.128/2617.76.5.129 to 17.76.5.19017.76.5.19162
2417.76.5.192/2617.76.5.193 to 17.76.5.25417.76.5.25562
2517.76.6.0/2617.76.6.1 to 17.76.6.6217.76.6.6362
2617.76.6.64/2617.76.6.65 to 17.76.6.12617.76.6.12762
2717.76.6.128/2617.76.6.129 to 17.76.6.19017.76.6.19162
2817.76.6.192/2617.76.6.193 to 17.76.6.25417.76.6.25562
2917.76.7.0/2617.76.7.1 to 17.76.7.6217.76.7.6362
3017.76.7.64/2617.76.7.65 to 17.76.7.12617.76.7.12762
3117.76.7.128/2617.76.7.129 to 17.76.7.19017.76.7.19162
3217.76.7.192/2617.76.7.193 to 17.76.7.25417.76.7.25562
3317.76.8.0/2617.76.8.1 to 17.76.8.6217.76.8.6362
3417.76.8.64/2617.76.8.65 to 17.76.8.12617.76.8.12762
3517.76.8.128/2617.76.8.129 to 17.76.8.19017.76.8.19162
3617.76.8.192/2617.76.8.193 to 17.76.8.25417.76.8.25562
3717.76.9.0/2617.76.9.1 to 17.76.9.6217.76.9.6362
3817.76.9.64/2617.76.9.65 to 17.76.9.12617.76.9.12762
3917.76.9.128/2617.76.9.129 to 17.76.9.19017.76.9.19162
4017.76.9.192/2617.76.9.193 to 17.76.9.25417.76.9.25562
4117.76.10.0/2617.76.10.1 to 17.76.10.6217.76.10.6362
4217.76.10.64/2617.76.10.65 to 17.76.10.12617.76.10.12762
4317.76.10.128/2617.76.10.129 to 17.76.10.19017.76.10.19162
4417.76.10.192/2617.76.10.193 to 17.76.10.25417.76.10.25562
4517.76.11.0/2617.76.11.1 to 17.76.11.6217.76.11.6362
4617.76.11.64/2617.76.11.65 to 17.76.11.12617.76.11.12762
4717.76.11.128/2617.76.11.129 to 17.76.11.19017.76.11.19162
4817.76.11.192/2617.76.11.193 to 17.76.11.25417.76.11.25562
4917.76.12.0/2617.76.12.1 to 17.76.12.6217.76.12.6362
5017.76.12.64/2617.76.12.65 to 17.76.12.12617.76.12.12762
5117.76.12.128/2617.76.12.129 to 17.76.12.19017.76.12.19162
5217.76.12.192/2617.76.12.193 to 17.76.12.25417.76.12.25562
5317.76.13.0/2617.76.13.1 to 17.76.13.6217.76.13.6362
5417.76.13.64/2617.76.13.65 to 17.76.13.12617.76.13.12762
5517.76.13.128/2617.76.13.129 to 17.76.13.19017.76.13.19162
5617.76.13.192/2617.76.13.193 to 17.76.13.25417.76.13.25562
5717.76.14.0/2617.76.14.1 to 17.76.14.6217.76.14.6362
5817.76.14.64/2617.76.14.65 to 17.76.14.12617.76.14.12762
5917.76.14.128/2617.76.14.129 to 17.76.14.19017.76.14.19162
6017.76.14.192/2617.76.14.193 to 17.76.14.25417.76.14.25562
6117.76.15.0/2617.76.15.1 to 17.76.15.6217.76.15.6362
6217.76.15.64/2617.76.15.65 to 17.76.15.12617.76.15.12762
6317.76.15.128/2617.76.15.129 to 17.76.15.19017.76.15.19162
6417.76.15.192/2617.76.15.193 to 17.76.15.25417.76.15.25562
6517.76.16.0/2617.76.16.1 to 17.76.16.6217.76.16.6362
6617.76.16.64/2617.76.16.65 to 17.76.16.12617.76.16.12762
6717.76.16.128/2617.76.16.129 to 17.76.16.19017.76.16.19162
6817.76.16.192/2617.76.16.193 to 17.76.16.25417.76.16.25562
6917.76.17.0/2617.76.17.1 to 17.76.17.6217.76.17.6362
7017.76.17.64/2617.76.17.65 to 17.76.17.12617.76.17.12762
7117.76.17.128/2617.76.17.129 to 17.76.17.19017.76.17.19162
7217.76.17.192/2617.76.17.193 to 17.76.17.25417.76.17.25562
7317.76.18.0/2617.76.18.1 to 17.76.18.6217.76.18.6362
7417.76.18.64/2617.76.18.65 to 17.76.18.12617.76.18.12762
7517.76.18.128/2617.76.18.129 to 17.76.18.19017.76.18.19162
7617.76.18.192/2617.76.18.193 to 17.76.18.25417.76.18.25562
7717.76.19.0/2617.76.19.1 to 17.76.19.6217.76.19.6362
7817.76.19.64/2617.76.19.65 to 17.76.19.12617.76.19.12762
7917.76.19.128/2617.76.19.129 to 17.76.19.19017.76.19.19162
8017.76.19.192/2617.76.19.193 to 17.76.19.25417.76.19.25562
8117.76.20.0/2617.76.20.1 to 17.76.20.6217.76.20.6362
8217.76.20.64/2617.76.20.65 to 17.76.20.12617.76.20.12762
8317.76.20.128/2617.76.20.129 to 17.76.20.19017.76.20.19162
8417.76.20.192/2617.76.20.193 to 17.76.20.25417.76.20.25562
8517.76.21.0/2617.76.21.1 to 17.76.21.6217.76.21.6362
8617.76.21.64/2617.76.21.65 to 17.76.21.12617.76.21.12762
8717.76.21.128/2617.76.21.129 to 17.76.21.19017.76.21.19162
8817.76.21.192/2617.76.21.193 to 17.76.21.25417.76.21.25562
8917.76.22.0/2617.76.22.1 to 17.76.22.6217.76.22.6362
9017.76.22.64/2617.76.22.65 to 17.76.22.12617.76.22.12762
9117.76.22.128/2617.76.22.129 to 17.76.22.19017.76.22.19162
9217.76.22.192/2617.76.22.193 to 17.76.22.25417.76.22.25562
9317.76.23.0/2617.76.23.1 to 17.76.23.6217.76.23.6362
9417.76.23.64/2617.76.23.65 to 17.76.23.12617.76.23.12762
9517.76.23.128/2617.76.23.129 to 17.76.23.19017.76.23.19162
9617.76.23.192/2617.76.23.193 to 17.76.23.25417.76.23.25562
9717.76.24.0/2617.76.24.1 to 17.76.24.6217.76.24.6362
9817.76.24.64/2617.76.24.65 to 17.76.24.12617.76.24.12762
9917.76.24.128/2617.76.24.129 to 17.76.24.19017.76.24.19162
10017.76.24.192/2617.76.24.193 to 17.76.24.25417.76.24.25562
10117.76.25.0/2617.76.25.1 to 17.76.25.6217.76.25.6362
10217.76.25.64/2617.76.25.65 to 17.76.25.12617.76.25.12762
10317.76.25.128/2617.76.25.129 to 17.76.25.19017.76.25.19162
10417.76.25.192/2617.76.25.193 to 17.76.25.25417.76.25.25562
10517.76.26.0/2617.76.26.1 to 17.76.26.6217.76.26.6362
10617.76.26.64/2617.76.26.65 to 17.76.26.12617.76.26.12762
10717.76.26.128/2617.76.26.129 to 17.76.26.19017.76.26.19162
10817.76.26.192/2617.76.26.193 to 17.76.26.25417.76.26.25562
10917.76.27.0/2617.76.27.1 to 17.76.27.6217.76.27.6362
11017.76.27.64/2617.76.27.65 to 17.76.27.12617.76.27.12762
11117.76.27.128/2617.76.27.129 to 17.76.27.19017.76.27.19162
11217.76.27.192/2617.76.27.193 to 17.76.27.25417.76.27.25562
11317.76.28.0/2617.76.28.1 to 17.76.28.6217.76.28.6362
11417.76.28.64/2617.76.28.65 to 17.76.28.12617.76.28.12762
11517.76.28.128/2617.76.28.129 to 17.76.28.19017.76.28.19162
11617.76.28.192/2617.76.28.193 to 17.76.28.25417.76.28.25562
11717.76.29.0/2617.76.29.1 to 17.76.29.6217.76.29.6362
11817.76.29.64/2617.76.29.65 to 17.76.29.12617.76.29.12762
11917.76.29.128/2617.76.29.129 to 17.76.29.19017.76.29.19162
12017.76.29.192/2617.76.29.193 to 17.76.29.25417.76.29.25562
12117.76.30.0/2617.76.30.1 to 17.76.30.6217.76.30.6362
12217.76.30.64/2617.76.30.65 to 17.76.30.12617.76.30.12762
12317.76.30.128/2617.76.30.129 to 17.76.30.19017.76.30.19162
12417.76.30.192/2617.76.30.193 to 17.76.30.25417.76.30.25562
12517.76.31.0/2617.76.31.1 to 17.76.31.6217.76.31.6362
12617.76.31.64/2617.76.31.65 to 17.76.31.12617.76.31.12762
12717.76.31.128/2617.76.31.129 to 17.76.31.19017.76.31.19162
12817.76.31.192/2617.76.31.193 to 17.76.31.25417.76.31.25562
12917.76.32.0/2617.76.32.1 to 17.76.32.6217.76.32.6362
13017.76.32.64/2617.76.32.65 to 17.76.32.12617.76.32.12762
13117.76.32.128/2617.76.32.129 to 17.76.32.19017.76.32.19162
13217.76.32.192/2617.76.32.193 to 17.76.32.25417.76.32.25562
13317.76.33.0/2617.76.33.1 to 17.76.33.6217.76.33.6362
13417.76.33.64/2617.76.33.65 to 17.76.33.12617.76.33.12762
13517.76.33.128/2617.76.33.129 to 17.76.33.19017.76.33.19162
13617.76.33.192/2617.76.33.193 to 17.76.33.25417.76.33.25562
13717.76.34.0/2617.76.34.1 to 17.76.34.6217.76.34.6362
13817.76.34.64/2617.76.34.65 to 17.76.34.12617.76.34.12762
13917.76.34.128/2617.76.34.129 to 17.76.34.19017.76.34.19162
14017.76.34.192/2617.76.34.193 to 17.76.34.25417.76.34.25562
14117.76.35.0/2617.76.35.1 to 17.76.35.6217.76.35.6362
14217.76.35.64/2617.76.35.65 to 17.76.35.12617.76.35.12762
14317.76.35.128/2617.76.35.129 to 17.76.35.19017.76.35.19162
14417.76.35.192/2617.76.35.193 to 17.76.35.25417.76.35.25562
14517.76.36.0/2617.76.36.1 to 17.76.36.6217.76.36.6362
14617.76.36.64/2617.76.36.65 to 17.76.36.12617.76.36.12762
14717.76.36.128/2617.76.36.129 to 17.76.36.19017.76.36.19162
14817.76.36.192/2617.76.36.193 to 17.76.36.25417.76.36.25562
14917.76.37.0/2617.76.37.1 to 17.76.37.6217.76.37.6362
15017.76.37.64/2617.76.37.65 to 17.76.37.12617.76.37.12762
15117.76.37.128/2617.76.37.129 to 17.76.37.19017.76.37.19162
15217.76.37.192/2617.76.37.193 to 17.76.37.25417.76.37.25562
15317.76.38.0/2617.76.38.1 to 17.76.38.6217.76.38.6362
15417.76.38.64/2617.76.38.65 to 17.76.38.12617.76.38.12762
15517.76.38.128/2617.76.38.129 to 17.76.38.19017.76.38.19162
15617.76.38.192/2617.76.38.193 to 17.76.38.25417.76.38.25562
15717.76.39.0/2617.76.39.1 to 17.76.39.6217.76.39.6362
15817.76.39.64/2617.76.39.65 to 17.76.39.12617.76.39.12762
15917.76.39.128/2617.76.39.129 to 17.76.39.19017.76.39.19162
16017.76.39.192/2617.76.39.193 to 17.76.39.25417.76.39.25562
16117.76.40.0/2617.76.40.1 to 17.76.40.6217.76.40.6362
16217.76.40.64/2617.76.40.65 to 17.76.40.12617.76.40.12762
16317.76.40.128/2617.76.40.129 to 17.76.40.19017.76.40.19162
16417.76.40.192/2617.76.40.193 to 17.76.40.25417.76.40.25562
16517.76.41.0/2617.76.41.1 to 17.76.41.6217.76.41.6362
16617.76.41.64/2617.76.41.65 to 17.76.41.12617.76.41.12762
16717.76.41.128/2617.76.41.129 to 17.76.41.19017.76.41.19162
16817.76.41.192/2617.76.41.193 to 17.76.41.25417.76.41.25562
16917.76.42.0/2617.76.42.1 to 17.76.42.6217.76.42.6362
17017.76.42.64/2617.76.42.65 to 17.76.42.12617.76.42.12762
17117.76.42.128/2617.76.42.129 to 17.76.42.19017.76.42.19162
17217.76.42.192/2617.76.42.193 to 17.76.42.25417.76.42.25562
17317.76.43.0/2617.76.43.1 to 17.76.43.6217.76.43.6362
17417.76.43.64/2617.76.43.65 to 17.76.43.12617.76.43.12762
17517.76.43.128/2617.76.43.129 to 17.76.43.19017.76.43.19162
17617.76.43.192/2617.76.43.193 to 17.76.43.25417.76.43.25562
17717.76.44.0/2617.76.44.1 to 17.76.44.6217.76.44.6362
17817.76.44.64/2617.76.44.65 to 17.76.44.12617.76.44.12762
17917.76.44.128/2617.76.44.129 to 17.76.44.19017.76.44.19162
18017.76.44.192/2617.76.44.193 to 17.76.44.25417.76.44.25562
18117.76.45.0/2617.76.45.1 to 17.76.45.6217.76.45.6362
18217.76.45.64/2617.76.45.65 to 17.76.45.12617.76.45.12762
18317.76.45.128/2617.76.45.129 to 17.76.45.19017.76.45.19162
18417.76.45.192/2617.76.45.193 to 17.76.45.25417.76.45.25562
18517.76.46.0/2617.76.46.1 to 17.76.46.6217.76.46.6362
18617.76.46.64/2617.76.46.65 to 17.76.46.12617.76.46.12762
18717.76.46.128/2617.76.46.129 to 17.76.46.19017.76.46.19162
18817.76.46.192/2617.76.46.193 to 17.76.46.25417.76.46.25562
18917.76.47.0/2617.76.47.1 to 17.76.47.6217.76.47.6362
19017.76.47.64/2617.76.47.65 to 17.76.47.12617.76.47.12762
19117.76.47.128/2617.76.47.129 to 17.76.47.19017.76.47.19162
19217.76.47.192/2617.76.47.193 to 17.76.47.25417.76.47.25562
19317.76.48.0/2617.76.48.1 to 17.76.48.6217.76.48.6362
19417.76.48.64/2617.76.48.65 to 17.76.48.12617.76.48.12762
19517.76.48.128/2617.76.48.129 to 17.76.48.19017.76.48.19162
19617.76.48.192/2617.76.48.193 to 17.76.48.25417.76.48.25562
19717.76.49.0/2617.76.49.1 to 17.76.49.6217.76.49.6362
19817.76.49.64/2617.76.49.65 to 17.76.49.12617.76.49.12762
19917.76.49.128/2617.76.49.129 to 17.76.49.19017.76.49.19162
20017.76.49.192/2617.76.49.193 to 17.76.49.25417.76.49.25562
20117.76.50.0/2617.76.50.1 to 17.76.50.6217.76.50.6362
20217.76.50.64/2617.76.50.65 to 17.76.50.12617.76.50.12762
20317.76.50.128/2617.76.50.129 to 17.76.50.19017.76.50.19162
20417.76.50.192/2617.76.50.193 to 17.76.50.25417.76.50.25562
20517.76.51.0/2617.76.51.1 to 17.76.51.6217.76.51.6362
20617.76.51.64/2617.76.51.65 to 17.76.51.12617.76.51.12762
20717.76.51.128/2617.76.51.129 to 17.76.51.19017.76.51.19162
20817.76.51.192/2617.76.51.193 to 17.76.51.25417.76.51.25562
20917.76.52.0/2617.76.52.1 to 17.76.52.6217.76.52.6362
21017.76.52.64/2617.76.52.65 to 17.76.52.12617.76.52.12762
21117.76.52.128/2617.76.52.129 to 17.76.52.19017.76.52.19162
21217.76.52.192/2617.76.52.193 to 17.76.52.25417.76.52.25562
21317.76.53.0/2617.76.53.1 to 17.76.53.6217.76.53.6362
21417.76.53.64/2617.76.53.65 to 17.76.53.12617.76.53.12762
21517.76.53.128/2617.76.53.129 to 17.76.53.19017.76.53.19162
21617.76.53.192/2617.76.53.193 to 17.76.53.25417.76.53.25562
21717.76.54.0/2617.76.54.1 to 17.76.54.6217.76.54.6362
21817.76.54.64/2617.76.54.65 to 17.76.54.12617.76.54.12762
21917.76.54.128/2617.76.54.129 to 17.76.54.19017.76.54.19162
22017.76.54.192/2617.76.54.193 to 17.76.54.25417.76.54.25562
22117.76.55.0/2617.76.55.1 to 17.76.55.6217.76.55.6362
22217.76.55.64/2617.76.55.65 to 17.76.55.12617.76.55.12762
22317.76.55.128/2617.76.55.129 to 17.76.55.19017.76.55.19162
22417.76.55.192/2617.76.55.193 to 17.76.55.25417.76.55.25562
22517.76.56.0/2617.76.56.1 to 17.76.56.6217.76.56.6362
22617.76.56.64/2617.76.56.65 to 17.76.56.12617.76.56.12762
22717.76.56.128/2617.76.56.129 to 17.76.56.19017.76.56.19162
22817.76.56.192/2617.76.56.193 to 17.76.56.25417.76.56.25562
22917.76.57.0/2617.76.57.1 to 17.76.57.6217.76.57.6362
23017.76.57.64/2617.76.57.65 to 17.76.57.12617.76.57.12762
23117.76.57.128/2617.76.57.129 to 17.76.57.19017.76.57.19162
23217.76.57.192/2617.76.57.193 to 17.76.57.25417.76.57.25562
23317.76.58.0/2617.76.58.1 to 17.76.58.6217.76.58.6362
23417.76.58.64/2617.76.58.65 to 17.76.58.12617.76.58.12762
23517.76.58.128/2617.76.58.129 to 17.76.58.19017.76.58.19162
23617.76.58.192/2617.76.58.193 to 17.76.58.25417.76.58.25562
23717.76.59.0/2617.76.59.1 to 17.76.59.6217.76.59.6362
23817.76.59.64/2617.76.59.65 to 17.76.59.12617.76.59.12762
23917.76.59.128/2617.76.59.129 to 17.76.59.19017.76.59.19162
24017.76.59.192/2617.76.59.193 to 17.76.59.25417.76.59.25562
24117.76.60.0/2617.76.60.1 to 17.76.60.6217.76.60.6362
24217.76.60.64/2617.76.60.65 to 17.76.60.12617.76.60.12762
24317.76.60.128/2617.76.60.129 to 17.76.60.19017.76.60.19162
24417.76.60.192/2617.76.60.193 to 17.76.60.25417.76.60.25562
24517.76.61.0/2617.76.61.1 to 17.76.61.6217.76.61.6362
24617.76.61.64/2617.76.61.65 to 17.76.61.12617.76.61.12762
24717.76.61.128/2617.76.61.129 to 17.76.61.19017.76.61.19162
24817.76.61.192/2617.76.61.193 to 17.76.61.25417.76.61.25562
24917.76.62.0/2617.76.62.1 to 17.76.62.6217.76.62.6362
25017.76.62.64/2617.76.62.65 to 17.76.62.12617.76.62.12762
25117.76.62.128/2617.76.62.129 to 17.76.62.19017.76.62.19162
25217.76.62.192/2617.76.62.193 to 17.76.62.25417.76.62.25562
25317.76.63.0/2617.76.63.1 to 17.76.63.6217.76.63.6362
25417.76.63.64/2617.76.63.65 to 17.76.63.12617.76.63.12762
25517.76.63.128/2617.76.63.129 to 17.76.63.19017.76.63.19162
25617.76.63.192/2617.76.63.193 to 17.76.63.25417.76.63.25562

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.