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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.

Network10.94.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
10.94.0.0
Broadcast address
10.94.255.255
First usable
10.94.0.1
Last usable
10.94.255.254
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
Private (RFC 1918) 10.0.0.0/8
Office and home networks; not routed on the internet
Old class
A (default /8)
As numbers
Hex 0A5E0000 · Integer 173932544 to 173998079
Reverse DNS zone
94.10.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00001010.01011110..00000000.0000000010.94.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network00001010.01011110..00000000.0000000010.94.0.0
Broadcast00001010.01011110..11111111.1111111110.94.255.255
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)

10.94.0.0/16 makes 512 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
110.94.0.0/2510.94.0.1 to 10.94.0.12610.94.0.127126
210.94.0.128/2510.94.0.129 to 10.94.0.25410.94.0.255126
310.94.1.0/2510.94.1.1 to 10.94.1.12610.94.1.127126
410.94.1.128/2510.94.1.129 to 10.94.1.25410.94.1.255126
510.94.2.0/2510.94.2.1 to 10.94.2.12610.94.2.127126
610.94.2.128/2510.94.2.129 to 10.94.2.25410.94.2.255126
710.94.3.0/2510.94.3.1 to 10.94.3.12610.94.3.127126
810.94.3.128/2510.94.3.129 to 10.94.3.25410.94.3.255126
910.94.4.0/2510.94.4.1 to 10.94.4.12610.94.4.127126
1010.94.4.128/2510.94.4.129 to 10.94.4.25410.94.4.255126
1110.94.5.0/2510.94.5.1 to 10.94.5.12610.94.5.127126
1210.94.5.128/2510.94.5.129 to 10.94.5.25410.94.5.255126
1310.94.6.0/2510.94.6.1 to 10.94.6.12610.94.6.127126
1410.94.6.128/2510.94.6.129 to 10.94.6.25410.94.6.255126
1510.94.7.0/2510.94.7.1 to 10.94.7.12610.94.7.127126
1610.94.7.128/2510.94.7.129 to 10.94.7.25410.94.7.255126
1710.94.8.0/2510.94.8.1 to 10.94.8.12610.94.8.127126
1810.94.8.128/2510.94.8.129 to 10.94.8.25410.94.8.255126
1910.94.9.0/2510.94.9.1 to 10.94.9.12610.94.9.127126
2010.94.9.128/2510.94.9.129 to 10.94.9.25410.94.9.255126
2110.94.10.0/2510.94.10.1 to 10.94.10.12610.94.10.127126
2210.94.10.128/2510.94.10.129 to 10.94.10.25410.94.10.255126
2310.94.11.0/2510.94.11.1 to 10.94.11.12610.94.11.127126
2410.94.11.128/2510.94.11.129 to 10.94.11.25410.94.11.255126
2510.94.12.0/2510.94.12.1 to 10.94.12.12610.94.12.127126
2610.94.12.128/2510.94.12.129 to 10.94.12.25410.94.12.255126
2710.94.13.0/2510.94.13.1 to 10.94.13.12610.94.13.127126
2810.94.13.128/2510.94.13.129 to 10.94.13.25410.94.13.255126
2910.94.14.0/2510.94.14.1 to 10.94.14.12610.94.14.127126
3010.94.14.128/2510.94.14.129 to 10.94.14.25410.94.14.255126
3110.94.15.0/2510.94.15.1 to 10.94.15.12610.94.15.127126
3210.94.15.128/2510.94.15.129 to 10.94.15.25410.94.15.255126
3310.94.16.0/2510.94.16.1 to 10.94.16.12610.94.16.127126
3410.94.16.128/2510.94.16.129 to 10.94.16.25410.94.16.255126
3510.94.17.0/2510.94.17.1 to 10.94.17.12610.94.17.127126
3610.94.17.128/2510.94.17.129 to 10.94.17.25410.94.17.255126
3710.94.18.0/2510.94.18.1 to 10.94.18.12610.94.18.127126
3810.94.18.128/2510.94.18.129 to 10.94.18.25410.94.18.255126
3910.94.19.0/2510.94.19.1 to 10.94.19.12610.94.19.127126
4010.94.19.128/2510.94.19.129 to 10.94.19.25410.94.19.255126
4110.94.20.0/2510.94.20.1 to 10.94.20.12610.94.20.127126
4210.94.20.128/2510.94.20.129 to 10.94.20.25410.94.20.255126
4310.94.21.0/2510.94.21.1 to 10.94.21.12610.94.21.127126
4410.94.21.128/2510.94.21.129 to 10.94.21.25410.94.21.255126
4510.94.22.0/2510.94.22.1 to 10.94.22.12610.94.22.127126
4610.94.22.128/2510.94.22.129 to 10.94.22.25410.94.22.255126
4710.94.23.0/2510.94.23.1 to 10.94.23.12610.94.23.127126
4810.94.23.128/2510.94.23.129 to 10.94.23.25410.94.23.255126
4910.94.24.0/2510.94.24.1 to 10.94.24.12610.94.24.127126
5010.94.24.128/2510.94.24.129 to 10.94.24.25410.94.24.255126
5110.94.25.0/2510.94.25.1 to 10.94.25.12610.94.25.127126
5210.94.25.128/2510.94.25.129 to 10.94.25.25410.94.25.255126
5310.94.26.0/2510.94.26.1 to 10.94.26.12610.94.26.127126
5410.94.26.128/2510.94.26.129 to 10.94.26.25410.94.26.255126
5510.94.27.0/2510.94.27.1 to 10.94.27.12610.94.27.127126
5610.94.27.128/2510.94.27.129 to 10.94.27.25410.94.27.255126
5710.94.28.0/2510.94.28.1 to 10.94.28.12610.94.28.127126
5810.94.28.128/2510.94.28.129 to 10.94.28.25410.94.28.255126
5910.94.29.0/2510.94.29.1 to 10.94.29.12610.94.29.127126
6010.94.29.128/2510.94.29.129 to 10.94.29.25410.94.29.255126
6110.94.30.0/2510.94.30.1 to 10.94.30.12610.94.30.127126
6210.94.30.128/2510.94.30.129 to 10.94.30.25410.94.30.255126
6310.94.31.0/2510.94.31.1 to 10.94.31.12610.94.31.127126
6410.94.31.128/2510.94.31.129 to 10.94.31.25410.94.31.255126
6510.94.32.0/2510.94.32.1 to 10.94.32.12610.94.32.127126
6610.94.32.128/2510.94.32.129 to 10.94.32.25410.94.32.255126
6710.94.33.0/2510.94.33.1 to 10.94.33.12610.94.33.127126
6810.94.33.128/2510.94.33.129 to 10.94.33.25410.94.33.255126
6910.94.34.0/2510.94.34.1 to 10.94.34.12610.94.34.127126
7010.94.34.128/2510.94.34.129 to 10.94.34.25410.94.34.255126
7110.94.35.0/2510.94.35.1 to 10.94.35.12610.94.35.127126
7210.94.35.128/2510.94.35.129 to 10.94.35.25410.94.35.255126
7310.94.36.0/2510.94.36.1 to 10.94.36.12610.94.36.127126
7410.94.36.128/2510.94.36.129 to 10.94.36.25410.94.36.255126
7510.94.37.0/2510.94.37.1 to 10.94.37.12610.94.37.127126
7610.94.37.128/2510.94.37.129 to 10.94.37.25410.94.37.255126
7710.94.38.0/2510.94.38.1 to 10.94.38.12610.94.38.127126
7810.94.38.128/2510.94.38.129 to 10.94.38.25410.94.38.255126
7910.94.39.0/2510.94.39.1 to 10.94.39.12610.94.39.127126
8010.94.39.128/2510.94.39.129 to 10.94.39.25410.94.39.255126
8110.94.40.0/2510.94.40.1 to 10.94.40.12610.94.40.127126
8210.94.40.128/2510.94.40.129 to 10.94.40.25410.94.40.255126
8310.94.41.0/2510.94.41.1 to 10.94.41.12610.94.41.127126
8410.94.41.128/2510.94.41.129 to 10.94.41.25410.94.41.255126
8510.94.42.0/2510.94.42.1 to 10.94.42.12610.94.42.127126
8610.94.42.128/2510.94.42.129 to 10.94.42.25410.94.42.255126
8710.94.43.0/2510.94.43.1 to 10.94.43.12610.94.43.127126
8810.94.43.128/2510.94.43.129 to 10.94.43.25410.94.43.255126
8910.94.44.0/2510.94.44.1 to 10.94.44.12610.94.44.127126
9010.94.44.128/2510.94.44.129 to 10.94.44.25410.94.44.255126
9110.94.45.0/2510.94.45.1 to 10.94.45.12610.94.45.127126
9210.94.45.128/2510.94.45.129 to 10.94.45.25410.94.45.255126
9310.94.46.0/2510.94.46.1 to 10.94.46.12610.94.46.127126
9410.94.46.128/2510.94.46.129 to 10.94.46.25410.94.46.255126
9510.94.47.0/2510.94.47.1 to 10.94.47.12610.94.47.127126
9610.94.47.128/2510.94.47.129 to 10.94.47.25410.94.47.255126
9710.94.48.0/2510.94.48.1 to 10.94.48.12610.94.48.127126
9810.94.48.128/2510.94.48.129 to 10.94.48.25410.94.48.255126
9910.94.49.0/2510.94.49.1 to 10.94.49.12610.94.49.127126
10010.94.49.128/2510.94.49.129 to 10.94.49.25410.94.49.255126
10110.94.50.0/2510.94.50.1 to 10.94.50.12610.94.50.127126
10210.94.50.128/2510.94.50.129 to 10.94.50.25410.94.50.255126
10310.94.51.0/2510.94.51.1 to 10.94.51.12610.94.51.127126
10410.94.51.128/2510.94.51.129 to 10.94.51.25410.94.51.255126
10510.94.52.0/2510.94.52.1 to 10.94.52.12610.94.52.127126
10610.94.52.128/2510.94.52.129 to 10.94.52.25410.94.52.255126
10710.94.53.0/2510.94.53.1 to 10.94.53.12610.94.53.127126
10810.94.53.128/2510.94.53.129 to 10.94.53.25410.94.53.255126
10910.94.54.0/2510.94.54.1 to 10.94.54.12610.94.54.127126
11010.94.54.128/2510.94.54.129 to 10.94.54.25410.94.54.255126
11110.94.55.0/2510.94.55.1 to 10.94.55.12610.94.55.127126
11210.94.55.128/2510.94.55.129 to 10.94.55.25410.94.55.255126
11310.94.56.0/2510.94.56.1 to 10.94.56.12610.94.56.127126
11410.94.56.128/2510.94.56.129 to 10.94.56.25410.94.56.255126
11510.94.57.0/2510.94.57.1 to 10.94.57.12610.94.57.127126
11610.94.57.128/2510.94.57.129 to 10.94.57.25410.94.57.255126
11710.94.58.0/2510.94.58.1 to 10.94.58.12610.94.58.127126
11810.94.58.128/2510.94.58.129 to 10.94.58.25410.94.58.255126
11910.94.59.0/2510.94.59.1 to 10.94.59.12610.94.59.127126
12010.94.59.128/2510.94.59.129 to 10.94.59.25410.94.59.255126
12110.94.60.0/2510.94.60.1 to 10.94.60.12610.94.60.127126
12210.94.60.128/2510.94.60.129 to 10.94.60.25410.94.60.255126
12310.94.61.0/2510.94.61.1 to 10.94.61.12610.94.61.127126
12410.94.61.128/2510.94.61.129 to 10.94.61.25410.94.61.255126
12510.94.62.0/2510.94.62.1 to 10.94.62.12610.94.62.127126
12610.94.62.128/2510.94.62.129 to 10.94.62.25410.94.62.255126
12710.94.63.0/2510.94.63.1 to 10.94.63.12610.94.63.127126
12810.94.63.128/2510.94.63.129 to 10.94.63.25410.94.63.255126
12910.94.64.0/2510.94.64.1 to 10.94.64.12610.94.64.127126
13010.94.64.128/2510.94.64.129 to 10.94.64.25410.94.64.255126
13110.94.65.0/2510.94.65.1 to 10.94.65.12610.94.65.127126
13210.94.65.128/2510.94.65.129 to 10.94.65.25410.94.65.255126
13310.94.66.0/2510.94.66.1 to 10.94.66.12610.94.66.127126
13410.94.66.128/2510.94.66.129 to 10.94.66.25410.94.66.255126
13510.94.67.0/2510.94.67.1 to 10.94.67.12610.94.67.127126
13610.94.67.128/2510.94.67.129 to 10.94.67.25410.94.67.255126
13710.94.68.0/2510.94.68.1 to 10.94.68.12610.94.68.127126
13810.94.68.128/2510.94.68.129 to 10.94.68.25410.94.68.255126
13910.94.69.0/2510.94.69.1 to 10.94.69.12610.94.69.127126
14010.94.69.128/2510.94.69.129 to 10.94.69.25410.94.69.255126
14110.94.70.0/2510.94.70.1 to 10.94.70.12610.94.70.127126
14210.94.70.128/2510.94.70.129 to 10.94.70.25410.94.70.255126
14310.94.71.0/2510.94.71.1 to 10.94.71.12610.94.71.127126
14410.94.71.128/2510.94.71.129 to 10.94.71.25410.94.71.255126
14510.94.72.0/2510.94.72.1 to 10.94.72.12610.94.72.127126
14610.94.72.128/2510.94.72.129 to 10.94.72.25410.94.72.255126
14710.94.73.0/2510.94.73.1 to 10.94.73.12610.94.73.127126
14810.94.73.128/2510.94.73.129 to 10.94.73.25410.94.73.255126
14910.94.74.0/2510.94.74.1 to 10.94.74.12610.94.74.127126
15010.94.74.128/2510.94.74.129 to 10.94.74.25410.94.74.255126
15110.94.75.0/2510.94.75.1 to 10.94.75.12610.94.75.127126
15210.94.75.128/2510.94.75.129 to 10.94.75.25410.94.75.255126
15310.94.76.0/2510.94.76.1 to 10.94.76.12610.94.76.127126
15410.94.76.128/2510.94.76.129 to 10.94.76.25410.94.76.255126
15510.94.77.0/2510.94.77.1 to 10.94.77.12610.94.77.127126
15610.94.77.128/2510.94.77.129 to 10.94.77.25410.94.77.255126
15710.94.78.0/2510.94.78.1 to 10.94.78.12610.94.78.127126
15810.94.78.128/2510.94.78.129 to 10.94.78.25410.94.78.255126
15910.94.79.0/2510.94.79.1 to 10.94.79.12610.94.79.127126
16010.94.79.128/2510.94.79.129 to 10.94.79.25410.94.79.255126
16110.94.80.0/2510.94.80.1 to 10.94.80.12610.94.80.127126
16210.94.80.128/2510.94.80.129 to 10.94.80.25410.94.80.255126
16310.94.81.0/2510.94.81.1 to 10.94.81.12610.94.81.127126
16410.94.81.128/2510.94.81.129 to 10.94.81.25410.94.81.255126
16510.94.82.0/2510.94.82.1 to 10.94.82.12610.94.82.127126
16610.94.82.128/2510.94.82.129 to 10.94.82.25410.94.82.255126
16710.94.83.0/2510.94.83.1 to 10.94.83.12610.94.83.127126
16810.94.83.128/2510.94.83.129 to 10.94.83.25410.94.83.255126
16910.94.84.0/2510.94.84.1 to 10.94.84.12610.94.84.127126
17010.94.84.128/2510.94.84.129 to 10.94.84.25410.94.84.255126
17110.94.85.0/2510.94.85.1 to 10.94.85.12610.94.85.127126
17210.94.85.128/2510.94.85.129 to 10.94.85.25410.94.85.255126
17310.94.86.0/2510.94.86.1 to 10.94.86.12610.94.86.127126
17410.94.86.128/2510.94.86.129 to 10.94.86.25410.94.86.255126
17510.94.87.0/2510.94.87.1 to 10.94.87.12610.94.87.127126
17610.94.87.128/2510.94.87.129 to 10.94.87.25410.94.87.255126
17710.94.88.0/2510.94.88.1 to 10.94.88.12610.94.88.127126
17810.94.88.128/2510.94.88.129 to 10.94.88.25410.94.88.255126
17910.94.89.0/2510.94.89.1 to 10.94.89.12610.94.89.127126
18010.94.89.128/2510.94.89.129 to 10.94.89.25410.94.89.255126
18110.94.90.0/2510.94.90.1 to 10.94.90.12610.94.90.127126
18210.94.90.128/2510.94.90.129 to 10.94.90.25410.94.90.255126
18310.94.91.0/2510.94.91.1 to 10.94.91.12610.94.91.127126
18410.94.91.128/2510.94.91.129 to 10.94.91.25410.94.91.255126
18510.94.92.0/2510.94.92.1 to 10.94.92.12610.94.92.127126
18610.94.92.128/2510.94.92.129 to 10.94.92.25410.94.92.255126
18710.94.93.0/2510.94.93.1 to 10.94.93.12610.94.93.127126
18810.94.93.128/2510.94.93.129 to 10.94.93.25410.94.93.255126
18910.94.94.0/2510.94.94.1 to 10.94.94.12610.94.94.127126
19010.94.94.128/2510.94.94.129 to 10.94.94.25410.94.94.255126
19110.94.95.0/2510.94.95.1 to 10.94.95.12610.94.95.127126
19210.94.95.128/2510.94.95.129 to 10.94.95.25410.94.95.255126
19310.94.96.0/2510.94.96.1 to 10.94.96.12610.94.96.127126
19410.94.96.128/2510.94.96.129 to 10.94.96.25410.94.96.255126
19510.94.97.0/2510.94.97.1 to 10.94.97.12610.94.97.127126
19610.94.97.128/2510.94.97.129 to 10.94.97.25410.94.97.255126
19710.94.98.0/2510.94.98.1 to 10.94.98.12610.94.98.127126
19810.94.98.128/2510.94.98.129 to 10.94.98.25410.94.98.255126
19910.94.99.0/2510.94.99.1 to 10.94.99.12610.94.99.127126
20010.94.99.128/2510.94.99.129 to 10.94.99.25410.94.99.255126
20110.94.100.0/2510.94.100.1 to 10.94.100.12610.94.100.127126
20210.94.100.128/2510.94.100.129 to 10.94.100.25410.94.100.255126
20310.94.101.0/2510.94.101.1 to 10.94.101.12610.94.101.127126
20410.94.101.128/2510.94.101.129 to 10.94.101.25410.94.101.255126
20510.94.102.0/2510.94.102.1 to 10.94.102.12610.94.102.127126
20610.94.102.128/2510.94.102.129 to 10.94.102.25410.94.102.255126
20710.94.103.0/2510.94.103.1 to 10.94.103.12610.94.103.127126
20810.94.103.128/2510.94.103.129 to 10.94.103.25410.94.103.255126
20910.94.104.0/2510.94.104.1 to 10.94.104.12610.94.104.127126
21010.94.104.128/2510.94.104.129 to 10.94.104.25410.94.104.255126
21110.94.105.0/2510.94.105.1 to 10.94.105.12610.94.105.127126
21210.94.105.128/2510.94.105.129 to 10.94.105.25410.94.105.255126
21310.94.106.0/2510.94.106.1 to 10.94.106.12610.94.106.127126
21410.94.106.128/2510.94.106.129 to 10.94.106.25410.94.106.255126
21510.94.107.0/2510.94.107.1 to 10.94.107.12610.94.107.127126
21610.94.107.128/2510.94.107.129 to 10.94.107.25410.94.107.255126
21710.94.108.0/2510.94.108.1 to 10.94.108.12610.94.108.127126
21810.94.108.128/2510.94.108.129 to 10.94.108.25410.94.108.255126
21910.94.109.0/2510.94.109.1 to 10.94.109.12610.94.109.127126
22010.94.109.128/2510.94.109.129 to 10.94.109.25410.94.109.255126
22110.94.110.0/2510.94.110.1 to 10.94.110.12610.94.110.127126
22210.94.110.128/2510.94.110.129 to 10.94.110.25410.94.110.255126
22310.94.111.0/2510.94.111.1 to 10.94.111.12610.94.111.127126
22410.94.111.128/2510.94.111.129 to 10.94.111.25410.94.111.255126
22510.94.112.0/2510.94.112.1 to 10.94.112.12610.94.112.127126
22610.94.112.128/2510.94.112.129 to 10.94.112.25410.94.112.255126
22710.94.113.0/2510.94.113.1 to 10.94.113.12610.94.113.127126
22810.94.113.128/2510.94.113.129 to 10.94.113.25410.94.113.255126
22910.94.114.0/2510.94.114.1 to 10.94.114.12610.94.114.127126
23010.94.114.128/2510.94.114.129 to 10.94.114.25410.94.114.255126
23110.94.115.0/2510.94.115.1 to 10.94.115.12610.94.115.127126
23210.94.115.128/2510.94.115.129 to 10.94.115.25410.94.115.255126
23310.94.116.0/2510.94.116.1 to 10.94.116.12610.94.116.127126
23410.94.116.128/2510.94.116.129 to 10.94.116.25410.94.116.255126
23510.94.117.0/2510.94.117.1 to 10.94.117.12610.94.117.127126
23610.94.117.128/2510.94.117.129 to 10.94.117.25410.94.117.255126
23710.94.118.0/2510.94.118.1 to 10.94.118.12610.94.118.127126
23810.94.118.128/2510.94.118.129 to 10.94.118.25410.94.118.255126
23910.94.119.0/2510.94.119.1 to 10.94.119.12610.94.119.127126
24010.94.119.128/2510.94.119.129 to 10.94.119.25410.94.119.255126
24110.94.120.0/2510.94.120.1 to 10.94.120.12610.94.120.127126
24210.94.120.128/2510.94.120.129 to 10.94.120.25410.94.120.255126
24310.94.121.0/2510.94.121.1 to 10.94.121.12610.94.121.127126
24410.94.121.128/2510.94.121.129 to 10.94.121.25410.94.121.255126
24510.94.122.0/2510.94.122.1 to 10.94.122.12610.94.122.127126
24610.94.122.128/2510.94.122.129 to 10.94.122.25410.94.122.255126
24710.94.123.0/2510.94.123.1 to 10.94.123.12610.94.123.127126
24810.94.123.128/2510.94.123.129 to 10.94.123.25410.94.123.255126
24910.94.124.0/2510.94.124.1 to 10.94.124.12610.94.124.127126
25010.94.124.128/2510.94.124.129 to 10.94.124.25410.94.124.255126
25110.94.125.0/2510.94.125.1 to 10.94.125.12610.94.125.127126
25210.94.125.128/2510.94.125.129 to 10.94.125.25410.94.125.255126
25310.94.126.0/2510.94.126.1 to 10.94.126.12610.94.126.127126
25410.94.126.128/2510.94.126.129 to 10.94.126.25410.94.126.255126
25510.94.127.0/2510.94.127.1 to 10.94.127.12610.94.127.127126
25610.94.127.128/2510.94.127.129 to 10.94.127.25410.94.127.255126

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.