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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.

Network98.63.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
98.63.0.0
Broadcast address
98.63.255.255
First usable
98.63.0.1
Last usable
98.63.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 623F0000 · Integer 1648295936 to 1648361471
Reverse DNS zone
63.98.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01100010.00111111..00000000.0000000098.63.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01100010.00111111..00000000.0000000098.63.0.0
Broadcast01100010.00111111..11111111.1111111198.63.255.255
Split into smaller subnets/25
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

98.63.0.0/16 makes 512 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
198.63.0.0/2598.63.0.1 to 98.63.0.12698.63.0.127126
298.63.0.128/2598.63.0.129 to 98.63.0.25498.63.0.255126
398.63.1.0/2598.63.1.1 to 98.63.1.12698.63.1.127126
498.63.1.128/2598.63.1.129 to 98.63.1.25498.63.1.255126
598.63.2.0/2598.63.2.1 to 98.63.2.12698.63.2.127126
698.63.2.128/2598.63.2.129 to 98.63.2.25498.63.2.255126
798.63.3.0/2598.63.3.1 to 98.63.3.12698.63.3.127126
898.63.3.128/2598.63.3.129 to 98.63.3.25498.63.3.255126
998.63.4.0/2598.63.4.1 to 98.63.4.12698.63.4.127126
1098.63.4.128/2598.63.4.129 to 98.63.4.25498.63.4.255126
1198.63.5.0/2598.63.5.1 to 98.63.5.12698.63.5.127126
1298.63.5.128/2598.63.5.129 to 98.63.5.25498.63.5.255126
1398.63.6.0/2598.63.6.1 to 98.63.6.12698.63.6.127126
1498.63.6.128/2598.63.6.129 to 98.63.6.25498.63.6.255126
1598.63.7.0/2598.63.7.1 to 98.63.7.12698.63.7.127126
1698.63.7.128/2598.63.7.129 to 98.63.7.25498.63.7.255126
1798.63.8.0/2598.63.8.1 to 98.63.8.12698.63.8.127126
1898.63.8.128/2598.63.8.129 to 98.63.8.25498.63.8.255126
1998.63.9.0/2598.63.9.1 to 98.63.9.12698.63.9.127126
2098.63.9.128/2598.63.9.129 to 98.63.9.25498.63.9.255126
2198.63.10.0/2598.63.10.1 to 98.63.10.12698.63.10.127126
2298.63.10.128/2598.63.10.129 to 98.63.10.25498.63.10.255126
2398.63.11.0/2598.63.11.1 to 98.63.11.12698.63.11.127126
2498.63.11.128/2598.63.11.129 to 98.63.11.25498.63.11.255126
2598.63.12.0/2598.63.12.1 to 98.63.12.12698.63.12.127126
2698.63.12.128/2598.63.12.129 to 98.63.12.25498.63.12.255126
2798.63.13.0/2598.63.13.1 to 98.63.13.12698.63.13.127126
2898.63.13.128/2598.63.13.129 to 98.63.13.25498.63.13.255126
2998.63.14.0/2598.63.14.1 to 98.63.14.12698.63.14.127126
3098.63.14.128/2598.63.14.129 to 98.63.14.25498.63.14.255126
3198.63.15.0/2598.63.15.1 to 98.63.15.12698.63.15.127126
3298.63.15.128/2598.63.15.129 to 98.63.15.25498.63.15.255126
3398.63.16.0/2598.63.16.1 to 98.63.16.12698.63.16.127126
3498.63.16.128/2598.63.16.129 to 98.63.16.25498.63.16.255126
3598.63.17.0/2598.63.17.1 to 98.63.17.12698.63.17.127126
3698.63.17.128/2598.63.17.129 to 98.63.17.25498.63.17.255126
3798.63.18.0/2598.63.18.1 to 98.63.18.12698.63.18.127126
3898.63.18.128/2598.63.18.129 to 98.63.18.25498.63.18.255126
3998.63.19.0/2598.63.19.1 to 98.63.19.12698.63.19.127126
4098.63.19.128/2598.63.19.129 to 98.63.19.25498.63.19.255126
4198.63.20.0/2598.63.20.1 to 98.63.20.12698.63.20.127126
4298.63.20.128/2598.63.20.129 to 98.63.20.25498.63.20.255126
4398.63.21.0/2598.63.21.1 to 98.63.21.12698.63.21.127126
4498.63.21.128/2598.63.21.129 to 98.63.21.25498.63.21.255126
4598.63.22.0/2598.63.22.1 to 98.63.22.12698.63.22.127126
4698.63.22.128/2598.63.22.129 to 98.63.22.25498.63.22.255126
4798.63.23.0/2598.63.23.1 to 98.63.23.12698.63.23.127126
4898.63.23.128/2598.63.23.129 to 98.63.23.25498.63.23.255126
4998.63.24.0/2598.63.24.1 to 98.63.24.12698.63.24.127126
5098.63.24.128/2598.63.24.129 to 98.63.24.25498.63.24.255126
5198.63.25.0/2598.63.25.1 to 98.63.25.12698.63.25.127126
5298.63.25.128/2598.63.25.129 to 98.63.25.25498.63.25.255126
5398.63.26.0/2598.63.26.1 to 98.63.26.12698.63.26.127126
5498.63.26.128/2598.63.26.129 to 98.63.26.25498.63.26.255126
5598.63.27.0/2598.63.27.1 to 98.63.27.12698.63.27.127126
5698.63.27.128/2598.63.27.129 to 98.63.27.25498.63.27.255126
5798.63.28.0/2598.63.28.1 to 98.63.28.12698.63.28.127126
5898.63.28.128/2598.63.28.129 to 98.63.28.25498.63.28.255126
5998.63.29.0/2598.63.29.1 to 98.63.29.12698.63.29.127126
6098.63.29.128/2598.63.29.129 to 98.63.29.25498.63.29.255126
6198.63.30.0/2598.63.30.1 to 98.63.30.12698.63.30.127126
6298.63.30.128/2598.63.30.129 to 98.63.30.25498.63.30.255126
6398.63.31.0/2598.63.31.1 to 98.63.31.12698.63.31.127126
6498.63.31.128/2598.63.31.129 to 98.63.31.25498.63.31.255126
6598.63.32.0/2598.63.32.1 to 98.63.32.12698.63.32.127126
6698.63.32.128/2598.63.32.129 to 98.63.32.25498.63.32.255126
6798.63.33.0/2598.63.33.1 to 98.63.33.12698.63.33.127126
6898.63.33.128/2598.63.33.129 to 98.63.33.25498.63.33.255126
6998.63.34.0/2598.63.34.1 to 98.63.34.12698.63.34.127126
7098.63.34.128/2598.63.34.129 to 98.63.34.25498.63.34.255126
7198.63.35.0/2598.63.35.1 to 98.63.35.12698.63.35.127126
7298.63.35.128/2598.63.35.129 to 98.63.35.25498.63.35.255126
7398.63.36.0/2598.63.36.1 to 98.63.36.12698.63.36.127126
7498.63.36.128/2598.63.36.129 to 98.63.36.25498.63.36.255126
7598.63.37.0/2598.63.37.1 to 98.63.37.12698.63.37.127126
7698.63.37.128/2598.63.37.129 to 98.63.37.25498.63.37.255126
7798.63.38.0/2598.63.38.1 to 98.63.38.12698.63.38.127126
7898.63.38.128/2598.63.38.129 to 98.63.38.25498.63.38.255126
7998.63.39.0/2598.63.39.1 to 98.63.39.12698.63.39.127126
8098.63.39.128/2598.63.39.129 to 98.63.39.25498.63.39.255126
8198.63.40.0/2598.63.40.1 to 98.63.40.12698.63.40.127126
8298.63.40.128/2598.63.40.129 to 98.63.40.25498.63.40.255126
8398.63.41.0/2598.63.41.1 to 98.63.41.12698.63.41.127126
8498.63.41.128/2598.63.41.129 to 98.63.41.25498.63.41.255126
8598.63.42.0/2598.63.42.1 to 98.63.42.12698.63.42.127126
8698.63.42.128/2598.63.42.129 to 98.63.42.25498.63.42.255126
8798.63.43.0/2598.63.43.1 to 98.63.43.12698.63.43.127126
8898.63.43.128/2598.63.43.129 to 98.63.43.25498.63.43.255126
8998.63.44.0/2598.63.44.1 to 98.63.44.12698.63.44.127126
9098.63.44.128/2598.63.44.129 to 98.63.44.25498.63.44.255126
9198.63.45.0/2598.63.45.1 to 98.63.45.12698.63.45.127126
9298.63.45.128/2598.63.45.129 to 98.63.45.25498.63.45.255126
9398.63.46.0/2598.63.46.1 to 98.63.46.12698.63.46.127126
9498.63.46.128/2598.63.46.129 to 98.63.46.25498.63.46.255126
9598.63.47.0/2598.63.47.1 to 98.63.47.12698.63.47.127126
9698.63.47.128/2598.63.47.129 to 98.63.47.25498.63.47.255126
9798.63.48.0/2598.63.48.1 to 98.63.48.12698.63.48.127126
9898.63.48.128/2598.63.48.129 to 98.63.48.25498.63.48.255126
9998.63.49.0/2598.63.49.1 to 98.63.49.12698.63.49.127126
10098.63.49.128/2598.63.49.129 to 98.63.49.25498.63.49.255126
10198.63.50.0/2598.63.50.1 to 98.63.50.12698.63.50.127126
10298.63.50.128/2598.63.50.129 to 98.63.50.25498.63.50.255126
10398.63.51.0/2598.63.51.1 to 98.63.51.12698.63.51.127126
10498.63.51.128/2598.63.51.129 to 98.63.51.25498.63.51.255126
10598.63.52.0/2598.63.52.1 to 98.63.52.12698.63.52.127126
10698.63.52.128/2598.63.52.129 to 98.63.52.25498.63.52.255126
10798.63.53.0/2598.63.53.1 to 98.63.53.12698.63.53.127126
10898.63.53.128/2598.63.53.129 to 98.63.53.25498.63.53.255126
10998.63.54.0/2598.63.54.1 to 98.63.54.12698.63.54.127126
11098.63.54.128/2598.63.54.129 to 98.63.54.25498.63.54.255126
11198.63.55.0/2598.63.55.1 to 98.63.55.12698.63.55.127126
11298.63.55.128/2598.63.55.129 to 98.63.55.25498.63.55.255126
11398.63.56.0/2598.63.56.1 to 98.63.56.12698.63.56.127126
11498.63.56.128/2598.63.56.129 to 98.63.56.25498.63.56.255126
11598.63.57.0/2598.63.57.1 to 98.63.57.12698.63.57.127126
11698.63.57.128/2598.63.57.129 to 98.63.57.25498.63.57.255126
11798.63.58.0/2598.63.58.1 to 98.63.58.12698.63.58.127126
11898.63.58.128/2598.63.58.129 to 98.63.58.25498.63.58.255126
11998.63.59.0/2598.63.59.1 to 98.63.59.12698.63.59.127126
12098.63.59.128/2598.63.59.129 to 98.63.59.25498.63.59.255126
12198.63.60.0/2598.63.60.1 to 98.63.60.12698.63.60.127126
12298.63.60.128/2598.63.60.129 to 98.63.60.25498.63.60.255126
12398.63.61.0/2598.63.61.1 to 98.63.61.12698.63.61.127126
12498.63.61.128/2598.63.61.129 to 98.63.61.25498.63.61.255126
12598.63.62.0/2598.63.62.1 to 98.63.62.12698.63.62.127126
12698.63.62.128/2598.63.62.129 to 98.63.62.25498.63.62.255126
12798.63.63.0/2598.63.63.1 to 98.63.63.12698.63.63.127126
12898.63.63.128/2598.63.63.129 to 98.63.63.25498.63.63.255126
12998.63.64.0/2598.63.64.1 to 98.63.64.12698.63.64.127126
13098.63.64.128/2598.63.64.129 to 98.63.64.25498.63.64.255126
13198.63.65.0/2598.63.65.1 to 98.63.65.12698.63.65.127126
13298.63.65.128/2598.63.65.129 to 98.63.65.25498.63.65.255126
13398.63.66.0/2598.63.66.1 to 98.63.66.12698.63.66.127126
13498.63.66.128/2598.63.66.129 to 98.63.66.25498.63.66.255126
13598.63.67.0/2598.63.67.1 to 98.63.67.12698.63.67.127126
13698.63.67.128/2598.63.67.129 to 98.63.67.25498.63.67.255126
13798.63.68.0/2598.63.68.1 to 98.63.68.12698.63.68.127126
13898.63.68.128/2598.63.68.129 to 98.63.68.25498.63.68.255126
13998.63.69.0/2598.63.69.1 to 98.63.69.12698.63.69.127126
14098.63.69.128/2598.63.69.129 to 98.63.69.25498.63.69.255126
14198.63.70.0/2598.63.70.1 to 98.63.70.12698.63.70.127126
14298.63.70.128/2598.63.70.129 to 98.63.70.25498.63.70.255126
14398.63.71.0/2598.63.71.1 to 98.63.71.12698.63.71.127126
14498.63.71.128/2598.63.71.129 to 98.63.71.25498.63.71.255126
14598.63.72.0/2598.63.72.1 to 98.63.72.12698.63.72.127126
14698.63.72.128/2598.63.72.129 to 98.63.72.25498.63.72.255126
14798.63.73.0/2598.63.73.1 to 98.63.73.12698.63.73.127126
14898.63.73.128/2598.63.73.129 to 98.63.73.25498.63.73.255126
14998.63.74.0/2598.63.74.1 to 98.63.74.12698.63.74.127126
15098.63.74.128/2598.63.74.129 to 98.63.74.25498.63.74.255126
15198.63.75.0/2598.63.75.1 to 98.63.75.12698.63.75.127126
15298.63.75.128/2598.63.75.129 to 98.63.75.25498.63.75.255126
15398.63.76.0/2598.63.76.1 to 98.63.76.12698.63.76.127126
15498.63.76.128/2598.63.76.129 to 98.63.76.25498.63.76.255126
15598.63.77.0/2598.63.77.1 to 98.63.77.12698.63.77.127126
15698.63.77.128/2598.63.77.129 to 98.63.77.25498.63.77.255126
15798.63.78.0/2598.63.78.1 to 98.63.78.12698.63.78.127126
15898.63.78.128/2598.63.78.129 to 98.63.78.25498.63.78.255126
15998.63.79.0/2598.63.79.1 to 98.63.79.12698.63.79.127126
16098.63.79.128/2598.63.79.129 to 98.63.79.25498.63.79.255126
16198.63.80.0/2598.63.80.1 to 98.63.80.12698.63.80.127126
16298.63.80.128/2598.63.80.129 to 98.63.80.25498.63.80.255126
16398.63.81.0/2598.63.81.1 to 98.63.81.12698.63.81.127126
16498.63.81.128/2598.63.81.129 to 98.63.81.25498.63.81.255126
16598.63.82.0/2598.63.82.1 to 98.63.82.12698.63.82.127126
16698.63.82.128/2598.63.82.129 to 98.63.82.25498.63.82.255126
16798.63.83.0/2598.63.83.1 to 98.63.83.12698.63.83.127126
16898.63.83.128/2598.63.83.129 to 98.63.83.25498.63.83.255126
16998.63.84.0/2598.63.84.1 to 98.63.84.12698.63.84.127126
17098.63.84.128/2598.63.84.129 to 98.63.84.25498.63.84.255126
17198.63.85.0/2598.63.85.1 to 98.63.85.12698.63.85.127126
17298.63.85.128/2598.63.85.129 to 98.63.85.25498.63.85.255126
17398.63.86.0/2598.63.86.1 to 98.63.86.12698.63.86.127126
17498.63.86.128/2598.63.86.129 to 98.63.86.25498.63.86.255126
17598.63.87.0/2598.63.87.1 to 98.63.87.12698.63.87.127126
17698.63.87.128/2598.63.87.129 to 98.63.87.25498.63.87.255126
17798.63.88.0/2598.63.88.1 to 98.63.88.12698.63.88.127126
17898.63.88.128/2598.63.88.129 to 98.63.88.25498.63.88.255126
17998.63.89.0/2598.63.89.1 to 98.63.89.12698.63.89.127126
18098.63.89.128/2598.63.89.129 to 98.63.89.25498.63.89.255126
18198.63.90.0/2598.63.90.1 to 98.63.90.12698.63.90.127126
18298.63.90.128/2598.63.90.129 to 98.63.90.25498.63.90.255126
18398.63.91.0/2598.63.91.1 to 98.63.91.12698.63.91.127126
18498.63.91.128/2598.63.91.129 to 98.63.91.25498.63.91.255126
18598.63.92.0/2598.63.92.1 to 98.63.92.12698.63.92.127126
18698.63.92.128/2598.63.92.129 to 98.63.92.25498.63.92.255126
18798.63.93.0/2598.63.93.1 to 98.63.93.12698.63.93.127126
18898.63.93.128/2598.63.93.129 to 98.63.93.25498.63.93.255126
18998.63.94.0/2598.63.94.1 to 98.63.94.12698.63.94.127126
19098.63.94.128/2598.63.94.129 to 98.63.94.25498.63.94.255126
19198.63.95.0/2598.63.95.1 to 98.63.95.12698.63.95.127126
19298.63.95.128/2598.63.95.129 to 98.63.95.25498.63.95.255126
19398.63.96.0/2598.63.96.1 to 98.63.96.12698.63.96.127126
19498.63.96.128/2598.63.96.129 to 98.63.96.25498.63.96.255126
19598.63.97.0/2598.63.97.1 to 98.63.97.12698.63.97.127126
19698.63.97.128/2598.63.97.129 to 98.63.97.25498.63.97.255126
19798.63.98.0/2598.63.98.1 to 98.63.98.12698.63.98.127126
19898.63.98.128/2598.63.98.129 to 98.63.98.25498.63.98.255126
19998.63.99.0/2598.63.99.1 to 98.63.99.12698.63.99.127126
20098.63.99.128/2598.63.99.129 to 98.63.99.25498.63.99.255126
20198.63.100.0/2598.63.100.1 to 98.63.100.12698.63.100.127126
20298.63.100.128/2598.63.100.129 to 98.63.100.25498.63.100.255126
20398.63.101.0/2598.63.101.1 to 98.63.101.12698.63.101.127126
20498.63.101.128/2598.63.101.129 to 98.63.101.25498.63.101.255126
20598.63.102.0/2598.63.102.1 to 98.63.102.12698.63.102.127126
20698.63.102.128/2598.63.102.129 to 98.63.102.25498.63.102.255126
20798.63.103.0/2598.63.103.1 to 98.63.103.12698.63.103.127126
20898.63.103.128/2598.63.103.129 to 98.63.103.25498.63.103.255126
20998.63.104.0/2598.63.104.1 to 98.63.104.12698.63.104.127126
21098.63.104.128/2598.63.104.129 to 98.63.104.25498.63.104.255126
21198.63.105.0/2598.63.105.1 to 98.63.105.12698.63.105.127126
21298.63.105.128/2598.63.105.129 to 98.63.105.25498.63.105.255126
21398.63.106.0/2598.63.106.1 to 98.63.106.12698.63.106.127126
21498.63.106.128/2598.63.106.129 to 98.63.106.25498.63.106.255126
21598.63.107.0/2598.63.107.1 to 98.63.107.12698.63.107.127126
21698.63.107.128/2598.63.107.129 to 98.63.107.25498.63.107.255126
21798.63.108.0/2598.63.108.1 to 98.63.108.12698.63.108.127126
21898.63.108.128/2598.63.108.129 to 98.63.108.25498.63.108.255126
21998.63.109.0/2598.63.109.1 to 98.63.109.12698.63.109.127126
22098.63.109.128/2598.63.109.129 to 98.63.109.25498.63.109.255126
22198.63.110.0/2598.63.110.1 to 98.63.110.12698.63.110.127126
22298.63.110.128/2598.63.110.129 to 98.63.110.25498.63.110.255126
22398.63.111.0/2598.63.111.1 to 98.63.111.12698.63.111.127126
22498.63.111.128/2598.63.111.129 to 98.63.111.25498.63.111.255126
22598.63.112.0/2598.63.112.1 to 98.63.112.12698.63.112.127126
22698.63.112.128/2598.63.112.129 to 98.63.112.25498.63.112.255126
22798.63.113.0/2598.63.113.1 to 98.63.113.12698.63.113.127126
22898.63.113.128/2598.63.113.129 to 98.63.113.25498.63.113.255126
22998.63.114.0/2598.63.114.1 to 98.63.114.12698.63.114.127126
23098.63.114.128/2598.63.114.129 to 98.63.114.25498.63.114.255126
23198.63.115.0/2598.63.115.1 to 98.63.115.12698.63.115.127126
23298.63.115.128/2598.63.115.129 to 98.63.115.25498.63.115.255126
23398.63.116.0/2598.63.116.1 to 98.63.116.12698.63.116.127126
23498.63.116.128/2598.63.116.129 to 98.63.116.25498.63.116.255126
23598.63.117.0/2598.63.117.1 to 98.63.117.12698.63.117.127126
23698.63.117.128/2598.63.117.129 to 98.63.117.25498.63.117.255126
23798.63.118.0/2598.63.118.1 to 98.63.118.12698.63.118.127126
23898.63.118.128/2598.63.118.129 to 98.63.118.25498.63.118.255126
23998.63.119.0/2598.63.119.1 to 98.63.119.12698.63.119.127126
24098.63.119.128/2598.63.119.129 to 98.63.119.25498.63.119.255126
24198.63.120.0/2598.63.120.1 to 98.63.120.12698.63.120.127126
24298.63.120.128/2598.63.120.129 to 98.63.120.25498.63.120.255126
24398.63.121.0/2598.63.121.1 to 98.63.121.12698.63.121.127126
24498.63.121.128/2598.63.121.129 to 98.63.121.25498.63.121.255126
24598.63.122.0/2598.63.122.1 to 98.63.122.12698.63.122.127126
24698.63.122.128/2598.63.122.129 to 98.63.122.25498.63.122.255126
24798.63.123.0/2598.63.123.1 to 98.63.123.12698.63.123.127126
24898.63.123.128/2598.63.123.129 to 98.63.123.25498.63.123.255126
24998.63.124.0/2598.63.124.1 to 98.63.124.12698.63.124.127126
25098.63.124.128/2598.63.124.129 to 98.63.124.25498.63.124.255126
25198.63.125.0/2598.63.125.1 to 98.63.125.12698.63.125.127126
25298.63.125.128/2598.63.125.129 to 98.63.125.25498.63.125.255126
25398.63.126.0/2598.63.126.1 to 98.63.126.12698.63.126.127126
25498.63.126.128/2598.63.126.129 to 98.63.126.25498.63.126.255126
25598.63.127.0/2598.63.127.1 to 98.63.127.12698.63.127.127126
25698.63.127.128/2598.63.127.129 to 98.63.127.25498.63.127.255126

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.