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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.

Network17.232.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
17.232.0.0
Broadcast address
17.235.255.255
First usable
17.232.0.1
Last usable
17.235.255.254
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 11E80000 · Integer 300417024 to 300679167
Reverse DNS zones
232.17.in-addr.arpa
233.17.in-addr.arpa
234.17.in-addr.arpa
235.17.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
Address00010001.11101000.00000000.0000000017.232.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00010001.11101000.00000000.0000000017.232.0.0
Broadcast00010001.11101011.11111111.1111111117.235.255.255
Split into smaller subnets/25
/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)

17.232.0.0/14 makes 2,048 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
117.232.0.0/2517.232.0.1 to 17.232.0.12617.232.0.127126
217.232.0.128/2517.232.0.129 to 17.232.0.25417.232.0.255126
317.232.1.0/2517.232.1.1 to 17.232.1.12617.232.1.127126
417.232.1.128/2517.232.1.129 to 17.232.1.25417.232.1.255126
517.232.2.0/2517.232.2.1 to 17.232.2.12617.232.2.127126
617.232.2.128/2517.232.2.129 to 17.232.2.25417.232.2.255126
717.232.3.0/2517.232.3.1 to 17.232.3.12617.232.3.127126
817.232.3.128/2517.232.3.129 to 17.232.3.25417.232.3.255126
917.232.4.0/2517.232.4.1 to 17.232.4.12617.232.4.127126
1017.232.4.128/2517.232.4.129 to 17.232.4.25417.232.4.255126
1117.232.5.0/2517.232.5.1 to 17.232.5.12617.232.5.127126
1217.232.5.128/2517.232.5.129 to 17.232.5.25417.232.5.255126
1317.232.6.0/2517.232.6.1 to 17.232.6.12617.232.6.127126
1417.232.6.128/2517.232.6.129 to 17.232.6.25417.232.6.255126
1517.232.7.0/2517.232.7.1 to 17.232.7.12617.232.7.127126
1617.232.7.128/2517.232.7.129 to 17.232.7.25417.232.7.255126
1717.232.8.0/2517.232.8.1 to 17.232.8.12617.232.8.127126
1817.232.8.128/2517.232.8.129 to 17.232.8.25417.232.8.255126
1917.232.9.0/2517.232.9.1 to 17.232.9.12617.232.9.127126
2017.232.9.128/2517.232.9.129 to 17.232.9.25417.232.9.255126
2117.232.10.0/2517.232.10.1 to 17.232.10.12617.232.10.127126
2217.232.10.128/2517.232.10.129 to 17.232.10.25417.232.10.255126
2317.232.11.0/2517.232.11.1 to 17.232.11.12617.232.11.127126
2417.232.11.128/2517.232.11.129 to 17.232.11.25417.232.11.255126
2517.232.12.0/2517.232.12.1 to 17.232.12.12617.232.12.127126
2617.232.12.128/2517.232.12.129 to 17.232.12.25417.232.12.255126
2717.232.13.0/2517.232.13.1 to 17.232.13.12617.232.13.127126
2817.232.13.128/2517.232.13.129 to 17.232.13.25417.232.13.255126
2917.232.14.0/2517.232.14.1 to 17.232.14.12617.232.14.127126
3017.232.14.128/2517.232.14.129 to 17.232.14.25417.232.14.255126
3117.232.15.0/2517.232.15.1 to 17.232.15.12617.232.15.127126
3217.232.15.128/2517.232.15.129 to 17.232.15.25417.232.15.255126
3317.232.16.0/2517.232.16.1 to 17.232.16.12617.232.16.127126
3417.232.16.128/2517.232.16.129 to 17.232.16.25417.232.16.255126
3517.232.17.0/2517.232.17.1 to 17.232.17.12617.232.17.127126
3617.232.17.128/2517.232.17.129 to 17.232.17.25417.232.17.255126
3717.232.18.0/2517.232.18.1 to 17.232.18.12617.232.18.127126
3817.232.18.128/2517.232.18.129 to 17.232.18.25417.232.18.255126
3917.232.19.0/2517.232.19.1 to 17.232.19.12617.232.19.127126
4017.232.19.128/2517.232.19.129 to 17.232.19.25417.232.19.255126
4117.232.20.0/2517.232.20.1 to 17.232.20.12617.232.20.127126
4217.232.20.128/2517.232.20.129 to 17.232.20.25417.232.20.255126
4317.232.21.0/2517.232.21.1 to 17.232.21.12617.232.21.127126
4417.232.21.128/2517.232.21.129 to 17.232.21.25417.232.21.255126
4517.232.22.0/2517.232.22.1 to 17.232.22.12617.232.22.127126
4617.232.22.128/2517.232.22.129 to 17.232.22.25417.232.22.255126
4717.232.23.0/2517.232.23.1 to 17.232.23.12617.232.23.127126
4817.232.23.128/2517.232.23.129 to 17.232.23.25417.232.23.255126
4917.232.24.0/2517.232.24.1 to 17.232.24.12617.232.24.127126
5017.232.24.128/2517.232.24.129 to 17.232.24.25417.232.24.255126
5117.232.25.0/2517.232.25.1 to 17.232.25.12617.232.25.127126
5217.232.25.128/2517.232.25.129 to 17.232.25.25417.232.25.255126
5317.232.26.0/2517.232.26.1 to 17.232.26.12617.232.26.127126
5417.232.26.128/2517.232.26.129 to 17.232.26.25417.232.26.255126
5517.232.27.0/2517.232.27.1 to 17.232.27.12617.232.27.127126
5617.232.27.128/2517.232.27.129 to 17.232.27.25417.232.27.255126
5717.232.28.0/2517.232.28.1 to 17.232.28.12617.232.28.127126
5817.232.28.128/2517.232.28.129 to 17.232.28.25417.232.28.255126
5917.232.29.0/2517.232.29.1 to 17.232.29.12617.232.29.127126
6017.232.29.128/2517.232.29.129 to 17.232.29.25417.232.29.255126
6117.232.30.0/2517.232.30.1 to 17.232.30.12617.232.30.127126
6217.232.30.128/2517.232.30.129 to 17.232.30.25417.232.30.255126
6317.232.31.0/2517.232.31.1 to 17.232.31.12617.232.31.127126
6417.232.31.128/2517.232.31.129 to 17.232.31.25417.232.31.255126
6517.232.32.0/2517.232.32.1 to 17.232.32.12617.232.32.127126
6617.232.32.128/2517.232.32.129 to 17.232.32.25417.232.32.255126
6717.232.33.0/2517.232.33.1 to 17.232.33.12617.232.33.127126
6817.232.33.128/2517.232.33.129 to 17.232.33.25417.232.33.255126
6917.232.34.0/2517.232.34.1 to 17.232.34.12617.232.34.127126
7017.232.34.128/2517.232.34.129 to 17.232.34.25417.232.34.255126
7117.232.35.0/2517.232.35.1 to 17.232.35.12617.232.35.127126
7217.232.35.128/2517.232.35.129 to 17.232.35.25417.232.35.255126
7317.232.36.0/2517.232.36.1 to 17.232.36.12617.232.36.127126
7417.232.36.128/2517.232.36.129 to 17.232.36.25417.232.36.255126
7517.232.37.0/2517.232.37.1 to 17.232.37.12617.232.37.127126
7617.232.37.128/2517.232.37.129 to 17.232.37.25417.232.37.255126
7717.232.38.0/2517.232.38.1 to 17.232.38.12617.232.38.127126
7817.232.38.128/2517.232.38.129 to 17.232.38.25417.232.38.255126
7917.232.39.0/2517.232.39.1 to 17.232.39.12617.232.39.127126
8017.232.39.128/2517.232.39.129 to 17.232.39.25417.232.39.255126
8117.232.40.0/2517.232.40.1 to 17.232.40.12617.232.40.127126
8217.232.40.128/2517.232.40.129 to 17.232.40.25417.232.40.255126
8317.232.41.0/2517.232.41.1 to 17.232.41.12617.232.41.127126
8417.232.41.128/2517.232.41.129 to 17.232.41.25417.232.41.255126
8517.232.42.0/2517.232.42.1 to 17.232.42.12617.232.42.127126
8617.232.42.128/2517.232.42.129 to 17.232.42.25417.232.42.255126
8717.232.43.0/2517.232.43.1 to 17.232.43.12617.232.43.127126
8817.232.43.128/2517.232.43.129 to 17.232.43.25417.232.43.255126
8917.232.44.0/2517.232.44.1 to 17.232.44.12617.232.44.127126
9017.232.44.128/2517.232.44.129 to 17.232.44.25417.232.44.255126
9117.232.45.0/2517.232.45.1 to 17.232.45.12617.232.45.127126
9217.232.45.128/2517.232.45.129 to 17.232.45.25417.232.45.255126
9317.232.46.0/2517.232.46.1 to 17.232.46.12617.232.46.127126
9417.232.46.128/2517.232.46.129 to 17.232.46.25417.232.46.255126
9517.232.47.0/2517.232.47.1 to 17.232.47.12617.232.47.127126
9617.232.47.128/2517.232.47.129 to 17.232.47.25417.232.47.255126
9717.232.48.0/2517.232.48.1 to 17.232.48.12617.232.48.127126
9817.232.48.128/2517.232.48.129 to 17.232.48.25417.232.48.255126
9917.232.49.0/2517.232.49.1 to 17.232.49.12617.232.49.127126
10017.232.49.128/2517.232.49.129 to 17.232.49.25417.232.49.255126
10117.232.50.0/2517.232.50.1 to 17.232.50.12617.232.50.127126
10217.232.50.128/2517.232.50.129 to 17.232.50.25417.232.50.255126
10317.232.51.0/2517.232.51.1 to 17.232.51.12617.232.51.127126
10417.232.51.128/2517.232.51.129 to 17.232.51.25417.232.51.255126
10517.232.52.0/2517.232.52.1 to 17.232.52.12617.232.52.127126
10617.232.52.128/2517.232.52.129 to 17.232.52.25417.232.52.255126
10717.232.53.0/2517.232.53.1 to 17.232.53.12617.232.53.127126
10817.232.53.128/2517.232.53.129 to 17.232.53.25417.232.53.255126
10917.232.54.0/2517.232.54.1 to 17.232.54.12617.232.54.127126
11017.232.54.128/2517.232.54.129 to 17.232.54.25417.232.54.255126
11117.232.55.0/2517.232.55.1 to 17.232.55.12617.232.55.127126
11217.232.55.128/2517.232.55.129 to 17.232.55.25417.232.55.255126
11317.232.56.0/2517.232.56.1 to 17.232.56.12617.232.56.127126
11417.232.56.128/2517.232.56.129 to 17.232.56.25417.232.56.255126
11517.232.57.0/2517.232.57.1 to 17.232.57.12617.232.57.127126
11617.232.57.128/2517.232.57.129 to 17.232.57.25417.232.57.255126
11717.232.58.0/2517.232.58.1 to 17.232.58.12617.232.58.127126
11817.232.58.128/2517.232.58.129 to 17.232.58.25417.232.58.255126
11917.232.59.0/2517.232.59.1 to 17.232.59.12617.232.59.127126
12017.232.59.128/2517.232.59.129 to 17.232.59.25417.232.59.255126
12117.232.60.0/2517.232.60.1 to 17.232.60.12617.232.60.127126
12217.232.60.128/2517.232.60.129 to 17.232.60.25417.232.60.255126
12317.232.61.0/2517.232.61.1 to 17.232.61.12617.232.61.127126
12417.232.61.128/2517.232.61.129 to 17.232.61.25417.232.61.255126
12517.232.62.0/2517.232.62.1 to 17.232.62.12617.232.62.127126
12617.232.62.128/2517.232.62.129 to 17.232.62.25417.232.62.255126
12717.232.63.0/2517.232.63.1 to 17.232.63.12617.232.63.127126
12817.232.63.128/2517.232.63.129 to 17.232.63.25417.232.63.255126
12917.232.64.0/2517.232.64.1 to 17.232.64.12617.232.64.127126
13017.232.64.128/2517.232.64.129 to 17.232.64.25417.232.64.255126
13117.232.65.0/2517.232.65.1 to 17.232.65.12617.232.65.127126
13217.232.65.128/2517.232.65.129 to 17.232.65.25417.232.65.255126
13317.232.66.0/2517.232.66.1 to 17.232.66.12617.232.66.127126
13417.232.66.128/2517.232.66.129 to 17.232.66.25417.232.66.255126
13517.232.67.0/2517.232.67.1 to 17.232.67.12617.232.67.127126
13617.232.67.128/2517.232.67.129 to 17.232.67.25417.232.67.255126
13717.232.68.0/2517.232.68.1 to 17.232.68.12617.232.68.127126
13817.232.68.128/2517.232.68.129 to 17.232.68.25417.232.68.255126
13917.232.69.0/2517.232.69.1 to 17.232.69.12617.232.69.127126
14017.232.69.128/2517.232.69.129 to 17.232.69.25417.232.69.255126
14117.232.70.0/2517.232.70.1 to 17.232.70.12617.232.70.127126
14217.232.70.128/2517.232.70.129 to 17.232.70.25417.232.70.255126
14317.232.71.0/2517.232.71.1 to 17.232.71.12617.232.71.127126
14417.232.71.128/2517.232.71.129 to 17.232.71.25417.232.71.255126
14517.232.72.0/2517.232.72.1 to 17.232.72.12617.232.72.127126
14617.232.72.128/2517.232.72.129 to 17.232.72.25417.232.72.255126
14717.232.73.0/2517.232.73.1 to 17.232.73.12617.232.73.127126
14817.232.73.128/2517.232.73.129 to 17.232.73.25417.232.73.255126
14917.232.74.0/2517.232.74.1 to 17.232.74.12617.232.74.127126
15017.232.74.128/2517.232.74.129 to 17.232.74.25417.232.74.255126
15117.232.75.0/2517.232.75.1 to 17.232.75.12617.232.75.127126
15217.232.75.128/2517.232.75.129 to 17.232.75.25417.232.75.255126
15317.232.76.0/2517.232.76.1 to 17.232.76.12617.232.76.127126
15417.232.76.128/2517.232.76.129 to 17.232.76.25417.232.76.255126
15517.232.77.0/2517.232.77.1 to 17.232.77.12617.232.77.127126
15617.232.77.128/2517.232.77.129 to 17.232.77.25417.232.77.255126
15717.232.78.0/2517.232.78.1 to 17.232.78.12617.232.78.127126
15817.232.78.128/2517.232.78.129 to 17.232.78.25417.232.78.255126
15917.232.79.0/2517.232.79.1 to 17.232.79.12617.232.79.127126
16017.232.79.128/2517.232.79.129 to 17.232.79.25417.232.79.255126
16117.232.80.0/2517.232.80.1 to 17.232.80.12617.232.80.127126
16217.232.80.128/2517.232.80.129 to 17.232.80.25417.232.80.255126
16317.232.81.0/2517.232.81.1 to 17.232.81.12617.232.81.127126
16417.232.81.128/2517.232.81.129 to 17.232.81.25417.232.81.255126
16517.232.82.0/2517.232.82.1 to 17.232.82.12617.232.82.127126
16617.232.82.128/2517.232.82.129 to 17.232.82.25417.232.82.255126
16717.232.83.0/2517.232.83.1 to 17.232.83.12617.232.83.127126
16817.232.83.128/2517.232.83.129 to 17.232.83.25417.232.83.255126
16917.232.84.0/2517.232.84.1 to 17.232.84.12617.232.84.127126
17017.232.84.128/2517.232.84.129 to 17.232.84.25417.232.84.255126
17117.232.85.0/2517.232.85.1 to 17.232.85.12617.232.85.127126
17217.232.85.128/2517.232.85.129 to 17.232.85.25417.232.85.255126
17317.232.86.0/2517.232.86.1 to 17.232.86.12617.232.86.127126
17417.232.86.128/2517.232.86.129 to 17.232.86.25417.232.86.255126
17517.232.87.0/2517.232.87.1 to 17.232.87.12617.232.87.127126
17617.232.87.128/2517.232.87.129 to 17.232.87.25417.232.87.255126
17717.232.88.0/2517.232.88.1 to 17.232.88.12617.232.88.127126
17817.232.88.128/2517.232.88.129 to 17.232.88.25417.232.88.255126
17917.232.89.0/2517.232.89.1 to 17.232.89.12617.232.89.127126
18017.232.89.128/2517.232.89.129 to 17.232.89.25417.232.89.255126
18117.232.90.0/2517.232.90.1 to 17.232.90.12617.232.90.127126
18217.232.90.128/2517.232.90.129 to 17.232.90.25417.232.90.255126
18317.232.91.0/2517.232.91.1 to 17.232.91.12617.232.91.127126
18417.232.91.128/2517.232.91.129 to 17.232.91.25417.232.91.255126
18517.232.92.0/2517.232.92.1 to 17.232.92.12617.232.92.127126
18617.232.92.128/2517.232.92.129 to 17.232.92.25417.232.92.255126
18717.232.93.0/2517.232.93.1 to 17.232.93.12617.232.93.127126
18817.232.93.128/2517.232.93.129 to 17.232.93.25417.232.93.255126
18917.232.94.0/2517.232.94.1 to 17.232.94.12617.232.94.127126
19017.232.94.128/2517.232.94.129 to 17.232.94.25417.232.94.255126
19117.232.95.0/2517.232.95.1 to 17.232.95.12617.232.95.127126
19217.232.95.128/2517.232.95.129 to 17.232.95.25417.232.95.255126
19317.232.96.0/2517.232.96.1 to 17.232.96.12617.232.96.127126
19417.232.96.128/2517.232.96.129 to 17.232.96.25417.232.96.255126
19517.232.97.0/2517.232.97.1 to 17.232.97.12617.232.97.127126
19617.232.97.128/2517.232.97.129 to 17.232.97.25417.232.97.255126
19717.232.98.0/2517.232.98.1 to 17.232.98.12617.232.98.127126
19817.232.98.128/2517.232.98.129 to 17.232.98.25417.232.98.255126
19917.232.99.0/2517.232.99.1 to 17.232.99.12617.232.99.127126
20017.232.99.128/2517.232.99.129 to 17.232.99.25417.232.99.255126
20117.232.100.0/2517.232.100.1 to 17.232.100.12617.232.100.127126
20217.232.100.128/2517.232.100.129 to 17.232.100.25417.232.100.255126
20317.232.101.0/2517.232.101.1 to 17.232.101.12617.232.101.127126
20417.232.101.128/2517.232.101.129 to 17.232.101.25417.232.101.255126
20517.232.102.0/2517.232.102.1 to 17.232.102.12617.232.102.127126
20617.232.102.128/2517.232.102.129 to 17.232.102.25417.232.102.255126
20717.232.103.0/2517.232.103.1 to 17.232.103.12617.232.103.127126
20817.232.103.128/2517.232.103.129 to 17.232.103.25417.232.103.255126
20917.232.104.0/2517.232.104.1 to 17.232.104.12617.232.104.127126
21017.232.104.128/2517.232.104.129 to 17.232.104.25417.232.104.255126
21117.232.105.0/2517.232.105.1 to 17.232.105.12617.232.105.127126
21217.232.105.128/2517.232.105.129 to 17.232.105.25417.232.105.255126
21317.232.106.0/2517.232.106.1 to 17.232.106.12617.232.106.127126
21417.232.106.128/2517.232.106.129 to 17.232.106.25417.232.106.255126
21517.232.107.0/2517.232.107.1 to 17.232.107.12617.232.107.127126
21617.232.107.128/2517.232.107.129 to 17.232.107.25417.232.107.255126
21717.232.108.0/2517.232.108.1 to 17.232.108.12617.232.108.127126
21817.232.108.128/2517.232.108.129 to 17.232.108.25417.232.108.255126
21917.232.109.0/2517.232.109.1 to 17.232.109.12617.232.109.127126
22017.232.109.128/2517.232.109.129 to 17.232.109.25417.232.109.255126
22117.232.110.0/2517.232.110.1 to 17.232.110.12617.232.110.127126
22217.232.110.128/2517.232.110.129 to 17.232.110.25417.232.110.255126
22317.232.111.0/2517.232.111.1 to 17.232.111.12617.232.111.127126
22417.232.111.128/2517.232.111.129 to 17.232.111.25417.232.111.255126
22517.232.112.0/2517.232.112.1 to 17.232.112.12617.232.112.127126
22617.232.112.128/2517.232.112.129 to 17.232.112.25417.232.112.255126
22717.232.113.0/2517.232.113.1 to 17.232.113.12617.232.113.127126
22817.232.113.128/2517.232.113.129 to 17.232.113.25417.232.113.255126
22917.232.114.0/2517.232.114.1 to 17.232.114.12617.232.114.127126
23017.232.114.128/2517.232.114.129 to 17.232.114.25417.232.114.255126
23117.232.115.0/2517.232.115.1 to 17.232.115.12617.232.115.127126
23217.232.115.128/2517.232.115.129 to 17.232.115.25417.232.115.255126
23317.232.116.0/2517.232.116.1 to 17.232.116.12617.232.116.127126
23417.232.116.128/2517.232.116.129 to 17.232.116.25417.232.116.255126
23517.232.117.0/2517.232.117.1 to 17.232.117.12617.232.117.127126
23617.232.117.128/2517.232.117.129 to 17.232.117.25417.232.117.255126
23717.232.118.0/2517.232.118.1 to 17.232.118.12617.232.118.127126
23817.232.118.128/2517.232.118.129 to 17.232.118.25417.232.118.255126
23917.232.119.0/2517.232.119.1 to 17.232.119.12617.232.119.127126
24017.232.119.128/2517.232.119.129 to 17.232.119.25417.232.119.255126
24117.232.120.0/2517.232.120.1 to 17.232.120.12617.232.120.127126
24217.232.120.128/2517.232.120.129 to 17.232.120.25417.232.120.255126
24317.232.121.0/2517.232.121.1 to 17.232.121.12617.232.121.127126
24417.232.121.128/2517.232.121.129 to 17.232.121.25417.232.121.255126
24517.232.122.0/2517.232.122.1 to 17.232.122.12617.232.122.127126
24617.232.122.128/2517.232.122.129 to 17.232.122.25417.232.122.255126
24717.232.123.0/2517.232.123.1 to 17.232.123.12617.232.123.127126
24817.232.123.128/2517.232.123.129 to 17.232.123.25417.232.123.255126
24917.232.124.0/2517.232.124.1 to 17.232.124.12617.232.124.127126
25017.232.124.128/2517.232.124.129 to 17.232.124.25417.232.124.255126
25117.232.125.0/2517.232.125.1 to 17.232.125.12617.232.125.127126
25217.232.125.128/2517.232.125.129 to 17.232.125.25417.232.125.255126
25317.232.126.0/2517.232.126.1 to 17.232.126.12617.232.126.127126
25417.232.126.128/2517.232.126.129 to 17.232.126.25417.232.126.255126
25517.232.127.0/2517.232.127.1 to 17.232.127.12617.232.127.127126
25617.232.127.128/2517.232.127.129 to 17.232.127.25417.232.127.255126

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.