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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.

Network98.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
98.0.0.0
Broadcast address
99.255.255.255
First usable
98.0.0.1
Last usable
99.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
A (default /8)
As numbers
Hex 62000000 · Integer 1644167168 to 1677721599
Reverse DNS zones
98.in-addr.arpa
99.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01100010.00000000.00000000.0000000098.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network01100010.00000000.00000000.0000000098.0.0.0
Broadcast01100011.11111111.11111111.1111111199.255.255.255
Split into smaller subnets/17
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

98.0.0.0/7 makes 1,024 subnets of /17; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
198.0.0.0/1798.0.0.1 to 98.0.127.25498.0.127.25532,766
298.0.128.0/1798.0.128.1 to 98.0.255.25498.0.255.25532,766
398.1.0.0/1798.1.0.1 to 98.1.127.25498.1.127.25532,766
498.1.128.0/1798.1.128.1 to 98.1.255.25498.1.255.25532,766
598.2.0.0/1798.2.0.1 to 98.2.127.25498.2.127.25532,766
698.2.128.0/1798.2.128.1 to 98.2.255.25498.2.255.25532,766
798.3.0.0/1798.3.0.1 to 98.3.127.25498.3.127.25532,766
898.3.128.0/1798.3.128.1 to 98.3.255.25498.3.255.25532,766
998.4.0.0/1798.4.0.1 to 98.4.127.25498.4.127.25532,766
1098.4.128.0/1798.4.128.1 to 98.4.255.25498.4.255.25532,766
1198.5.0.0/1798.5.0.1 to 98.5.127.25498.5.127.25532,766
1298.5.128.0/1798.5.128.1 to 98.5.255.25498.5.255.25532,766
1398.6.0.0/1798.6.0.1 to 98.6.127.25498.6.127.25532,766
1498.6.128.0/1798.6.128.1 to 98.6.255.25498.6.255.25532,766
1598.7.0.0/1798.7.0.1 to 98.7.127.25498.7.127.25532,766
1698.7.128.0/1798.7.128.1 to 98.7.255.25498.7.255.25532,766
1798.8.0.0/1798.8.0.1 to 98.8.127.25498.8.127.25532,766
1898.8.128.0/1798.8.128.1 to 98.8.255.25498.8.255.25532,766
1998.9.0.0/1798.9.0.1 to 98.9.127.25498.9.127.25532,766
2098.9.128.0/1798.9.128.1 to 98.9.255.25498.9.255.25532,766
2198.10.0.0/1798.10.0.1 to 98.10.127.25498.10.127.25532,766
2298.10.128.0/1798.10.128.1 to 98.10.255.25498.10.255.25532,766
2398.11.0.0/1798.11.0.1 to 98.11.127.25498.11.127.25532,766
2498.11.128.0/1798.11.128.1 to 98.11.255.25498.11.255.25532,766
2598.12.0.0/1798.12.0.1 to 98.12.127.25498.12.127.25532,766
2698.12.128.0/1798.12.128.1 to 98.12.255.25498.12.255.25532,766
2798.13.0.0/1798.13.0.1 to 98.13.127.25498.13.127.25532,766
2898.13.128.0/1798.13.128.1 to 98.13.255.25498.13.255.25532,766
2998.14.0.0/1798.14.0.1 to 98.14.127.25498.14.127.25532,766
3098.14.128.0/1798.14.128.1 to 98.14.255.25498.14.255.25532,766
3198.15.0.0/1798.15.0.1 to 98.15.127.25498.15.127.25532,766
3298.15.128.0/1798.15.128.1 to 98.15.255.25498.15.255.25532,766
3398.16.0.0/1798.16.0.1 to 98.16.127.25498.16.127.25532,766
3498.16.128.0/1798.16.128.1 to 98.16.255.25498.16.255.25532,766
3598.17.0.0/1798.17.0.1 to 98.17.127.25498.17.127.25532,766
3698.17.128.0/1798.17.128.1 to 98.17.255.25498.17.255.25532,766
3798.18.0.0/1798.18.0.1 to 98.18.127.25498.18.127.25532,766
3898.18.128.0/1798.18.128.1 to 98.18.255.25498.18.255.25532,766
3998.19.0.0/1798.19.0.1 to 98.19.127.25498.19.127.25532,766
4098.19.128.0/1798.19.128.1 to 98.19.255.25498.19.255.25532,766
4198.20.0.0/1798.20.0.1 to 98.20.127.25498.20.127.25532,766
4298.20.128.0/1798.20.128.1 to 98.20.255.25498.20.255.25532,766
4398.21.0.0/1798.21.0.1 to 98.21.127.25498.21.127.25532,766
4498.21.128.0/1798.21.128.1 to 98.21.255.25498.21.255.25532,766
4598.22.0.0/1798.22.0.1 to 98.22.127.25498.22.127.25532,766
4698.22.128.0/1798.22.128.1 to 98.22.255.25498.22.255.25532,766
4798.23.0.0/1798.23.0.1 to 98.23.127.25498.23.127.25532,766
4898.23.128.0/1798.23.128.1 to 98.23.255.25498.23.255.25532,766
4998.24.0.0/1798.24.0.1 to 98.24.127.25498.24.127.25532,766
5098.24.128.0/1798.24.128.1 to 98.24.255.25498.24.255.25532,766
5198.25.0.0/1798.25.0.1 to 98.25.127.25498.25.127.25532,766
5298.25.128.0/1798.25.128.1 to 98.25.255.25498.25.255.25532,766
5398.26.0.0/1798.26.0.1 to 98.26.127.25498.26.127.25532,766
5498.26.128.0/1798.26.128.1 to 98.26.255.25498.26.255.25532,766
5598.27.0.0/1798.27.0.1 to 98.27.127.25498.27.127.25532,766
5698.27.128.0/1798.27.128.1 to 98.27.255.25498.27.255.25532,766
5798.28.0.0/1798.28.0.1 to 98.28.127.25498.28.127.25532,766
5898.28.128.0/1798.28.128.1 to 98.28.255.25498.28.255.25532,766
5998.29.0.0/1798.29.0.1 to 98.29.127.25498.29.127.25532,766
6098.29.128.0/1798.29.128.1 to 98.29.255.25498.29.255.25532,766
6198.30.0.0/1798.30.0.1 to 98.30.127.25498.30.127.25532,766
6298.30.128.0/1798.30.128.1 to 98.30.255.25498.30.255.25532,766
6398.31.0.0/1798.31.0.1 to 98.31.127.25498.31.127.25532,766
6498.31.128.0/1798.31.128.1 to 98.31.255.25498.31.255.25532,766
6598.32.0.0/1798.32.0.1 to 98.32.127.25498.32.127.25532,766
6698.32.128.0/1798.32.128.1 to 98.32.255.25498.32.255.25532,766
6798.33.0.0/1798.33.0.1 to 98.33.127.25498.33.127.25532,766
6898.33.128.0/1798.33.128.1 to 98.33.255.25498.33.255.25532,766
6998.34.0.0/1798.34.0.1 to 98.34.127.25498.34.127.25532,766
7098.34.128.0/1798.34.128.1 to 98.34.255.25498.34.255.25532,766
7198.35.0.0/1798.35.0.1 to 98.35.127.25498.35.127.25532,766
7298.35.128.0/1798.35.128.1 to 98.35.255.25498.35.255.25532,766
7398.36.0.0/1798.36.0.1 to 98.36.127.25498.36.127.25532,766
7498.36.128.0/1798.36.128.1 to 98.36.255.25498.36.255.25532,766
7598.37.0.0/1798.37.0.1 to 98.37.127.25498.37.127.25532,766
7698.37.128.0/1798.37.128.1 to 98.37.255.25498.37.255.25532,766
7798.38.0.0/1798.38.0.1 to 98.38.127.25498.38.127.25532,766
7898.38.128.0/1798.38.128.1 to 98.38.255.25498.38.255.25532,766
7998.39.0.0/1798.39.0.1 to 98.39.127.25498.39.127.25532,766
8098.39.128.0/1798.39.128.1 to 98.39.255.25498.39.255.25532,766
8198.40.0.0/1798.40.0.1 to 98.40.127.25498.40.127.25532,766
8298.40.128.0/1798.40.128.1 to 98.40.255.25498.40.255.25532,766
8398.41.0.0/1798.41.0.1 to 98.41.127.25498.41.127.25532,766
8498.41.128.0/1798.41.128.1 to 98.41.255.25498.41.255.25532,766
8598.42.0.0/1798.42.0.1 to 98.42.127.25498.42.127.25532,766
8698.42.128.0/1798.42.128.1 to 98.42.255.25498.42.255.25532,766
8798.43.0.0/1798.43.0.1 to 98.43.127.25498.43.127.25532,766
8898.43.128.0/1798.43.128.1 to 98.43.255.25498.43.255.25532,766
8998.44.0.0/1798.44.0.1 to 98.44.127.25498.44.127.25532,766
9098.44.128.0/1798.44.128.1 to 98.44.255.25498.44.255.25532,766
9198.45.0.0/1798.45.0.1 to 98.45.127.25498.45.127.25532,766
9298.45.128.0/1798.45.128.1 to 98.45.255.25498.45.255.25532,766
9398.46.0.0/1798.46.0.1 to 98.46.127.25498.46.127.25532,766
9498.46.128.0/1798.46.128.1 to 98.46.255.25498.46.255.25532,766
9598.47.0.0/1798.47.0.1 to 98.47.127.25498.47.127.25532,766
9698.47.128.0/1798.47.128.1 to 98.47.255.25498.47.255.25532,766
9798.48.0.0/1798.48.0.1 to 98.48.127.25498.48.127.25532,766
9898.48.128.0/1798.48.128.1 to 98.48.255.25498.48.255.25532,766
9998.49.0.0/1798.49.0.1 to 98.49.127.25498.49.127.25532,766
10098.49.128.0/1798.49.128.1 to 98.49.255.25498.49.255.25532,766
10198.50.0.0/1798.50.0.1 to 98.50.127.25498.50.127.25532,766
10298.50.128.0/1798.50.128.1 to 98.50.255.25498.50.255.25532,766
10398.51.0.0/1798.51.0.1 to 98.51.127.25498.51.127.25532,766
10498.51.128.0/1798.51.128.1 to 98.51.255.25498.51.255.25532,766
10598.52.0.0/1798.52.0.1 to 98.52.127.25498.52.127.25532,766
10698.52.128.0/1798.52.128.1 to 98.52.255.25498.52.255.25532,766
10798.53.0.0/1798.53.0.1 to 98.53.127.25498.53.127.25532,766
10898.53.128.0/1798.53.128.1 to 98.53.255.25498.53.255.25532,766
10998.54.0.0/1798.54.0.1 to 98.54.127.25498.54.127.25532,766
11098.54.128.0/1798.54.128.1 to 98.54.255.25498.54.255.25532,766
11198.55.0.0/1798.55.0.1 to 98.55.127.25498.55.127.25532,766
11298.55.128.0/1798.55.128.1 to 98.55.255.25498.55.255.25532,766
11398.56.0.0/1798.56.0.1 to 98.56.127.25498.56.127.25532,766
11498.56.128.0/1798.56.128.1 to 98.56.255.25498.56.255.25532,766
11598.57.0.0/1798.57.0.1 to 98.57.127.25498.57.127.25532,766
11698.57.128.0/1798.57.128.1 to 98.57.255.25498.57.255.25532,766
11798.58.0.0/1798.58.0.1 to 98.58.127.25498.58.127.25532,766
11898.58.128.0/1798.58.128.1 to 98.58.255.25498.58.255.25532,766
11998.59.0.0/1798.59.0.1 to 98.59.127.25498.59.127.25532,766
12098.59.128.0/1798.59.128.1 to 98.59.255.25498.59.255.25532,766
12198.60.0.0/1798.60.0.1 to 98.60.127.25498.60.127.25532,766
12298.60.128.0/1798.60.128.1 to 98.60.255.25498.60.255.25532,766
12398.61.0.0/1798.61.0.1 to 98.61.127.25498.61.127.25532,766
12498.61.128.0/1798.61.128.1 to 98.61.255.25498.61.255.25532,766
12598.62.0.0/1798.62.0.1 to 98.62.127.25498.62.127.25532,766
12698.62.128.0/1798.62.128.1 to 98.62.255.25498.62.255.25532,766
12798.63.0.0/1798.63.0.1 to 98.63.127.25498.63.127.25532,766
12898.63.128.0/1798.63.128.1 to 98.63.255.25498.63.255.25532,766
12998.64.0.0/1798.64.0.1 to 98.64.127.25498.64.127.25532,766
13098.64.128.0/1798.64.128.1 to 98.64.255.25498.64.255.25532,766
13198.65.0.0/1798.65.0.1 to 98.65.127.25498.65.127.25532,766
13298.65.128.0/1798.65.128.1 to 98.65.255.25498.65.255.25532,766
13398.66.0.0/1798.66.0.1 to 98.66.127.25498.66.127.25532,766
13498.66.128.0/1798.66.128.1 to 98.66.255.25498.66.255.25532,766
13598.67.0.0/1798.67.0.1 to 98.67.127.25498.67.127.25532,766
13698.67.128.0/1798.67.128.1 to 98.67.255.25498.67.255.25532,766
13798.68.0.0/1798.68.0.1 to 98.68.127.25498.68.127.25532,766
13898.68.128.0/1798.68.128.1 to 98.68.255.25498.68.255.25532,766
13998.69.0.0/1798.69.0.1 to 98.69.127.25498.69.127.25532,766
14098.69.128.0/1798.69.128.1 to 98.69.255.25498.69.255.25532,766
14198.70.0.0/1798.70.0.1 to 98.70.127.25498.70.127.25532,766
14298.70.128.0/1798.70.128.1 to 98.70.255.25498.70.255.25532,766
14398.71.0.0/1798.71.0.1 to 98.71.127.25498.71.127.25532,766
14498.71.128.0/1798.71.128.1 to 98.71.255.25498.71.255.25532,766
14598.72.0.0/1798.72.0.1 to 98.72.127.25498.72.127.25532,766
14698.72.128.0/1798.72.128.1 to 98.72.255.25498.72.255.25532,766
14798.73.0.0/1798.73.0.1 to 98.73.127.25498.73.127.25532,766
14898.73.128.0/1798.73.128.1 to 98.73.255.25498.73.255.25532,766
14998.74.0.0/1798.74.0.1 to 98.74.127.25498.74.127.25532,766
15098.74.128.0/1798.74.128.1 to 98.74.255.25498.74.255.25532,766
15198.75.0.0/1798.75.0.1 to 98.75.127.25498.75.127.25532,766
15298.75.128.0/1798.75.128.1 to 98.75.255.25498.75.255.25532,766
15398.76.0.0/1798.76.0.1 to 98.76.127.25498.76.127.25532,766
15498.76.128.0/1798.76.128.1 to 98.76.255.25498.76.255.25532,766
15598.77.0.0/1798.77.0.1 to 98.77.127.25498.77.127.25532,766
15698.77.128.0/1798.77.128.1 to 98.77.255.25498.77.255.25532,766
15798.78.0.0/1798.78.0.1 to 98.78.127.25498.78.127.25532,766
15898.78.128.0/1798.78.128.1 to 98.78.255.25498.78.255.25532,766
15998.79.0.0/1798.79.0.1 to 98.79.127.25498.79.127.25532,766
16098.79.128.0/1798.79.128.1 to 98.79.255.25498.79.255.25532,766
16198.80.0.0/1798.80.0.1 to 98.80.127.25498.80.127.25532,766
16298.80.128.0/1798.80.128.1 to 98.80.255.25498.80.255.25532,766
16398.81.0.0/1798.81.0.1 to 98.81.127.25498.81.127.25532,766
16498.81.128.0/1798.81.128.1 to 98.81.255.25498.81.255.25532,766
16598.82.0.0/1798.82.0.1 to 98.82.127.25498.82.127.25532,766
16698.82.128.0/1798.82.128.1 to 98.82.255.25498.82.255.25532,766
16798.83.0.0/1798.83.0.1 to 98.83.127.25498.83.127.25532,766
16898.83.128.0/1798.83.128.1 to 98.83.255.25498.83.255.25532,766
16998.84.0.0/1798.84.0.1 to 98.84.127.25498.84.127.25532,766
17098.84.128.0/1798.84.128.1 to 98.84.255.25498.84.255.25532,766
17198.85.0.0/1798.85.0.1 to 98.85.127.25498.85.127.25532,766
17298.85.128.0/1798.85.128.1 to 98.85.255.25498.85.255.25532,766
17398.86.0.0/1798.86.0.1 to 98.86.127.25498.86.127.25532,766
17498.86.128.0/1798.86.128.1 to 98.86.255.25498.86.255.25532,766
17598.87.0.0/1798.87.0.1 to 98.87.127.25498.87.127.25532,766
17698.87.128.0/1798.87.128.1 to 98.87.255.25498.87.255.25532,766
17798.88.0.0/1798.88.0.1 to 98.88.127.25498.88.127.25532,766
17898.88.128.0/1798.88.128.1 to 98.88.255.25498.88.255.25532,766
17998.89.0.0/1798.89.0.1 to 98.89.127.25498.89.127.25532,766
18098.89.128.0/1798.89.128.1 to 98.89.255.25498.89.255.25532,766
18198.90.0.0/1798.90.0.1 to 98.90.127.25498.90.127.25532,766
18298.90.128.0/1798.90.128.1 to 98.90.255.25498.90.255.25532,766
18398.91.0.0/1798.91.0.1 to 98.91.127.25498.91.127.25532,766
18498.91.128.0/1798.91.128.1 to 98.91.255.25498.91.255.25532,766
18598.92.0.0/1798.92.0.1 to 98.92.127.25498.92.127.25532,766
18698.92.128.0/1798.92.128.1 to 98.92.255.25498.92.255.25532,766
18798.93.0.0/1798.93.0.1 to 98.93.127.25498.93.127.25532,766
18898.93.128.0/1798.93.128.1 to 98.93.255.25498.93.255.25532,766
18998.94.0.0/1798.94.0.1 to 98.94.127.25498.94.127.25532,766
19098.94.128.0/1798.94.128.1 to 98.94.255.25498.94.255.25532,766
19198.95.0.0/1798.95.0.1 to 98.95.127.25498.95.127.25532,766
19298.95.128.0/1798.95.128.1 to 98.95.255.25498.95.255.25532,766
19398.96.0.0/1798.96.0.1 to 98.96.127.25498.96.127.25532,766
19498.96.128.0/1798.96.128.1 to 98.96.255.25498.96.255.25532,766
19598.97.0.0/1798.97.0.1 to 98.97.127.25498.97.127.25532,766
19698.97.128.0/1798.97.128.1 to 98.97.255.25498.97.255.25532,766
19798.98.0.0/1798.98.0.1 to 98.98.127.25498.98.127.25532,766
19898.98.128.0/1798.98.128.1 to 98.98.255.25498.98.255.25532,766
19998.99.0.0/1798.99.0.1 to 98.99.127.25498.99.127.25532,766
20098.99.128.0/1798.99.128.1 to 98.99.255.25498.99.255.25532,766
20198.100.0.0/1798.100.0.1 to 98.100.127.25498.100.127.25532,766
20298.100.128.0/1798.100.128.1 to 98.100.255.25498.100.255.25532,766
20398.101.0.0/1798.101.0.1 to 98.101.127.25498.101.127.25532,766
20498.101.128.0/1798.101.128.1 to 98.101.255.25498.101.255.25532,766
20598.102.0.0/1798.102.0.1 to 98.102.127.25498.102.127.25532,766
20698.102.128.0/1798.102.128.1 to 98.102.255.25498.102.255.25532,766
20798.103.0.0/1798.103.0.1 to 98.103.127.25498.103.127.25532,766
20898.103.128.0/1798.103.128.1 to 98.103.255.25498.103.255.25532,766
20998.104.0.0/1798.104.0.1 to 98.104.127.25498.104.127.25532,766
21098.104.128.0/1798.104.128.1 to 98.104.255.25498.104.255.25532,766
21198.105.0.0/1798.105.0.1 to 98.105.127.25498.105.127.25532,766
21298.105.128.0/1798.105.128.1 to 98.105.255.25498.105.255.25532,766
21398.106.0.0/1798.106.0.1 to 98.106.127.25498.106.127.25532,766
21498.106.128.0/1798.106.128.1 to 98.106.255.25498.106.255.25532,766
21598.107.0.0/1798.107.0.1 to 98.107.127.25498.107.127.25532,766
21698.107.128.0/1798.107.128.1 to 98.107.255.25498.107.255.25532,766
21798.108.0.0/1798.108.0.1 to 98.108.127.25498.108.127.25532,766
21898.108.128.0/1798.108.128.1 to 98.108.255.25498.108.255.25532,766
21998.109.0.0/1798.109.0.1 to 98.109.127.25498.109.127.25532,766
22098.109.128.0/1798.109.128.1 to 98.109.255.25498.109.255.25532,766
22198.110.0.0/1798.110.0.1 to 98.110.127.25498.110.127.25532,766
22298.110.128.0/1798.110.128.1 to 98.110.255.25498.110.255.25532,766
22398.111.0.0/1798.111.0.1 to 98.111.127.25498.111.127.25532,766
22498.111.128.0/1798.111.128.1 to 98.111.255.25498.111.255.25532,766
22598.112.0.0/1798.112.0.1 to 98.112.127.25498.112.127.25532,766
22698.112.128.0/1798.112.128.1 to 98.112.255.25498.112.255.25532,766
22798.113.0.0/1798.113.0.1 to 98.113.127.25498.113.127.25532,766
22898.113.128.0/1798.113.128.1 to 98.113.255.25498.113.255.25532,766
22998.114.0.0/1798.114.0.1 to 98.114.127.25498.114.127.25532,766
23098.114.128.0/1798.114.128.1 to 98.114.255.25498.114.255.25532,766
23198.115.0.0/1798.115.0.1 to 98.115.127.25498.115.127.25532,766
23298.115.128.0/1798.115.128.1 to 98.115.255.25498.115.255.25532,766
23398.116.0.0/1798.116.0.1 to 98.116.127.25498.116.127.25532,766
23498.116.128.0/1798.116.128.1 to 98.116.255.25498.116.255.25532,766
23598.117.0.0/1798.117.0.1 to 98.117.127.25498.117.127.25532,766
23698.117.128.0/1798.117.128.1 to 98.117.255.25498.117.255.25532,766
23798.118.0.0/1798.118.0.1 to 98.118.127.25498.118.127.25532,766
23898.118.128.0/1798.118.128.1 to 98.118.255.25498.118.255.25532,766
23998.119.0.0/1798.119.0.1 to 98.119.127.25498.119.127.25532,766
24098.119.128.0/1798.119.128.1 to 98.119.255.25498.119.255.25532,766
24198.120.0.0/1798.120.0.1 to 98.120.127.25498.120.127.25532,766
24298.120.128.0/1798.120.128.1 to 98.120.255.25498.120.255.25532,766
24398.121.0.0/1798.121.0.1 to 98.121.127.25498.121.127.25532,766
24498.121.128.0/1798.121.128.1 to 98.121.255.25498.121.255.25532,766
24598.122.0.0/1798.122.0.1 to 98.122.127.25498.122.127.25532,766
24698.122.128.0/1798.122.128.1 to 98.122.255.25498.122.255.25532,766
24798.123.0.0/1798.123.0.1 to 98.123.127.25498.123.127.25532,766
24898.123.128.0/1798.123.128.1 to 98.123.255.25498.123.255.25532,766
24998.124.0.0/1798.124.0.1 to 98.124.127.25498.124.127.25532,766
25098.124.128.0/1798.124.128.1 to 98.124.255.25498.124.255.25532,766
25198.125.0.0/1798.125.0.1 to 98.125.127.25498.125.127.25532,766
25298.125.128.0/1798.125.128.1 to 98.125.255.25498.125.255.25532,766
25398.126.0.0/1798.126.0.1 to 98.126.127.25498.126.127.25532,766
25498.126.128.0/1798.126.128.1 to 98.126.255.25498.126.255.25532,766
25598.127.0.0/1798.127.0.1 to 98.127.127.25498.127.127.25532,766
25698.127.128.0/1798.127.128.1 to 98.127.255.25498.127.255.25532,766

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.