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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.

Network14.131.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
14.131.0.0
Broadcast address
14.131.255.255
First usable
14.131.0.1
Last usable
14.131.255.254
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 0E830000 · Integer 243466240 to 243531775
Reverse DNS zone
131.14.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00001110.10000011..00000000.0000000014.131.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network00001110.10000011..00000000.0000000014.131.0.0
Broadcast00001110.10000011..11111111.1111111114.131.255.255
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)

14.131.0.0/16 makes 512 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
114.131.0.0/2514.131.0.1 to 14.131.0.12614.131.0.127126
214.131.0.128/2514.131.0.129 to 14.131.0.25414.131.0.255126
314.131.1.0/2514.131.1.1 to 14.131.1.12614.131.1.127126
414.131.1.128/2514.131.1.129 to 14.131.1.25414.131.1.255126
514.131.2.0/2514.131.2.1 to 14.131.2.12614.131.2.127126
614.131.2.128/2514.131.2.129 to 14.131.2.25414.131.2.255126
714.131.3.0/2514.131.3.1 to 14.131.3.12614.131.3.127126
814.131.3.128/2514.131.3.129 to 14.131.3.25414.131.3.255126
914.131.4.0/2514.131.4.1 to 14.131.4.12614.131.4.127126
1014.131.4.128/2514.131.4.129 to 14.131.4.25414.131.4.255126
1114.131.5.0/2514.131.5.1 to 14.131.5.12614.131.5.127126
1214.131.5.128/2514.131.5.129 to 14.131.5.25414.131.5.255126
1314.131.6.0/2514.131.6.1 to 14.131.6.12614.131.6.127126
1414.131.6.128/2514.131.6.129 to 14.131.6.25414.131.6.255126
1514.131.7.0/2514.131.7.1 to 14.131.7.12614.131.7.127126
1614.131.7.128/2514.131.7.129 to 14.131.7.25414.131.7.255126
1714.131.8.0/2514.131.8.1 to 14.131.8.12614.131.8.127126
1814.131.8.128/2514.131.8.129 to 14.131.8.25414.131.8.255126
1914.131.9.0/2514.131.9.1 to 14.131.9.12614.131.9.127126
2014.131.9.128/2514.131.9.129 to 14.131.9.25414.131.9.255126
2114.131.10.0/2514.131.10.1 to 14.131.10.12614.131.10.127126
2214.131.10.128/2514.131.10.129 to 14.131.10.25414.131.10.255126
2314.131.11.0/2514.131.11.1 to 14.131.11.12614.131.11.127126
2414.131.11.128/2514.131.11.129 to 14.131.11.25414.131.11.255126
2514.131.12.0/2514.131.12.1 to 14.131.12.12614.131.12.127126
2614.131.12.128/2514.131.12.129 to 14.131.12.25414.131.12.255126
2714.131.13.0/2514.131.13.1 to 14.131.13.12614.131.13.127126
2814.131.13.128/2514.131.13.129 to 14.131.13.25414.131.13.255126
2914.131.14.0/2514.131.14.1 to 14.131.14.12614.131.14.127126
3014.131.14.128/2514.131.14.129 to 14.131.14.25414.131.14.255126
3114.131.15.0/2514.131.15.1 to 14.131.15.12614.131.15.127126
3214.131.15.128/2514.131.15.129 to 14.131.15.25414.131.15.255126
3314.131.16.0/2514.131.16.1 to 14.131.16.12614.131.16.127126
3414.131.16.128/2514.131.16.129 to 14.131.16.25414.131.16.255126
3514.131.17.0/2514.131.17.1 to 14.131.17.12614.131.17.127126
3614.131.17.128/2514.131.17.129 to 14.131.17.25414.131.17.255126
3714.131.18.0/2514.131.18.1 to 14.131.18.12614.131.18.127126
3814.131.18.128/2514.131.18.129 to 14.131.18.25414.131.18.255126
3914.131.19.0/2514.131.19.1 to 14.131.19.12614.131.19.127126
4014.131.19.128/2514.131.19.129 to 14.131.19.25414.131.19.255126
4114.131.20.0/2514.131.20.1 to 14.131.20.12614.131.20.127126
4214.131.20.128/2514.131.20.129 to 14.131.20.25414.131.20.255126
4314.131.21.0/2514.131.21.1 to 14.131.21.12614.131.21.127126
4414.131.21.128/2514.131.21.129 to 14.131.21.25414.131.21.255126
4514.131.22.0/2514.131.22.1 to 14.131.22.12614.131.22.127126
4614.131.22.128/2514.131.22.129 to 14.131.22.25414.131.22.255126
4714.131.23.0/2514.131.23.1 to 14.131.23.12614.131.23.127126
4814.131.23.128/2514.131.23.129 to 14.131.23.25414.131.23.255126
4914.131.24.0/2514.131.24.1 to 14.131.24.12614.131.24.127126
5014.131.24.128/2514.131.24.129 to 14.131.24.25414.131.24.255126
5114.131.25.0/2514.131.25.1 to 14.131.25.12614.131.25.127126
5214.131.25.128/2514.131.25.129 to 14.131.25.25414.131.25.255126
5314.131.26.0/2514.131.26.1 to 14.131.26.12614.131.26.127126
5414.131.26.128/2514.131.26.129 to 14.131.26.25414.131.26.255126
5514.131.27.0/2514.131.27.1 to 14.131.27.12614.131.27.127126
5614.131.27.128/2514.131.27.129 to 14.131.27.25414.131.27.255126
5714.131.28.0/2514.131.28.1 to 14.131.28.12614.131.28.127126
5814.131.28.128/2514.131.28.129 to 14.131.28.25414.131.28.255126
5914.131.29.0/2514.131.29.1 to 14.131.29.12614.131.29.127126
6014.131.29.128/2514.131.29.129 to 14.131.29.25414.131.29.255126
6114.131.30.0/2514.131.30.1 to 14.131.30.12614.131.30.127126
6214.131.30.128/2514.131.30.129 to 14.131.30.25414.131.30.255126
6314.131.31.0/2514.131.31.1 to 14.131.31.12614.131.31.127126
6414.131.31.128/2514.131.31.129 to 14.131.31.25414.131.31.255126
6514.131.32.0/2514.131.32.1 to 14.131.32.12614.131.32.127126
6614.131.32.128/2514.131.32.129 to 14.131.32.25414.131.32.255126
6714.131.33.0/2514.131.33.1 to 14.131.33.12614.131.33.127126
6814.131.33.128/2514.131.33.129 to 14.131.33.25414.131.33.255126
6914.131.34.0/2514.131.34.1 to 14.131.34.12614.131.34.127126
7014.131.34.128/2514.131.34.129 to 14.131.34.25414.131.34.255126
7114.131.35.0/2514.131.35.1 to 14.131.35.12614.131.35.127126
7214.131.35.128/2514.131.35.129 to 14.131.35.25414.131.35.255126
7314.131.36.0/2514.131.36.1 to 14.131.36.12614.131.36.127126
7414.131.36.128/2514.131.36.129 to 14.131.36.25414.131.36.255126
7514.131.37.0/2514.131.37.1 to 14.131.37.12614.131.37.127126
7614.131.37.128/2514.131.37.129 to 14.131.37.25414.131.37.255126
7714.131.38.0/2514.131.38.1 to 14.131.38.12614.131.38.127126
7814.131.38.128/2514.131.38.129 to 14.131.38.25414.131.38.255126
7914.131.39.0/2514.131.39.1 to 14.131.39.12614.131.39.127126
8014.131.39.128/2514.131.39.129 to 14.131.39.25414.131.39.255126
8114.131.40.0/2514.131.40.1 to 14.131.40.12614.131.40.127126
8214.131.40.128/2514.131.40.129 to 14.131.40.25414.131.40.255126
8314.131.41.0/2514.131.41.1 to 14.131.41.12614.131.41.127126
8414.131.41.128/2514.131.41.129 to 14.131.41.25414.131.41.255126
8514.131.42.0/2514.131.42.1 to 14.131.42.12614.131.42.127126
8614.131.42.128/2514.131.42.129 to 14.131.42.25414.131.42.255126
8714.131.43.0/2514.131.43.1 to 14.131.43.12614.131.43.127126
8814.131.43.128/2514.131.43.129 to 14.131.43.25414.131.43.255126
8914.131.44.0/2514.131.44.1 to 14.131.44.12614.131.44.127126
9014.131.44.128/2514.131.44.129 to 14.131.44.25414.131.44.255126
9114.131.45.0/2514.131.45.1 to 14.131.45.12614.131.45.127126
9214.131.45.128/2514.131.45.129 to 14.131.45.25414.131.45.255126
9314.131.46.0/2514.131.46.1 to 14.131.46.12614.131.46.127126
9414.131.46.128/2514.131.46.129 to 14.131.46.25414.131.46.255126
9514.131.47.0/2514.131.47.1 to 14.131.47.12614.131.47.127126
9614.131.47.128/2514.131.47.129 to 14.131.47.25414.131.47.255126
9714.131.48.0/2514.131.48.1 to 14.131.48.12614.131.48.127126
9814.131.48.128/2514.131.48.129 to 14.131.48.25414.131.48.255126
9914.131.49.0/2514.131.49.1 to 14.131.49.12614.131.49.127126
10014.131.49.128/2514.131.49.129 to 14.131.49.25414.131.49.255126
10114.131.50.0/2514.131.50.1 to 14.131.50.12614.131.50.127126
10214.131.50.128/2514.131.50.129 to 14.131.50.25414.131.50.255126
10314.131.51.0/2514.131.51.1 to 14.131.51.12614.131.51.127126
10414.131.51.128/2514.131.51.129 to 14.131.51.25414.131.51.255126
10514.131.52.0/2514.131.52.1 to 14.131.52.12614.131.52.127126
10614.131.52.128/2514.131.52.129 to 14.131.52.25414.131.52.255126
10714.131.53.0/2514.131.53.1 to 14.131.53.12614.131.53.127126
10814.131.53.128/2514.131.53.129 to 14.131.53.25414.131.53.255126
10914.131.54.0/2514.131.54.1 to 14.131.54.12614.131.54.127126
11014.131.54.128/2514.131.54.129 to 14.131.54.25414.131.54.255126
11114.131.55.0/2514.131.55.1 to 14.131.55.12614.131.55.127126
11214.131.55.128/2514.131.55.129 to 14.131.55.25414.131.55.255126
11314.131.56.0/2514.131.56.1 to 14.131.56.12614.131.56.127126
11414.131.56.128/2514.131.56.129 to 14.131.56.25414.131.56.255126
11514.131.57.0/2514.131.57.1 to 14.131.57.12614.131.57.127126
11614.131.57.128/2514.131.57.129 to 14.131.57.25414.131.57.255126
11714.131.58.0/2514.131.58.1 to 14.131.58.12614.131.58.127126
11814.131.58.128/2514.131.58.129 to 14.131.58.25414.131.58.255126
11914.131.59.0/2514.131.59.1 to 14.131.59.12614.131.59.127126
12014.131.59.128/2514.131.59.129 to 14.131.59.25414.131.59.255126
12114.131.60.0/2514.131.60.1 to 14.131.60.12614.131.60.127126
12214.131.60.128/2514.131.60.129 to 14.131.60.25414.131.60.255126
12314.131.61.0/2514.131.61.1 to 14.131.61.12614.131.61.127126
12414.131.61.128/2514.131.61.129 to 14.131.61.25414.131.61.255126
12514.131.62.0/2514.131.62.1 to 14.131.62.12614.131.62.127126
12614.131.62.128/2514.131.62.129 to 14.131.62.25414.131.62.255126
12714.131.63.0/2514.131.63.1 to 14.131.63.12614.131.63.127126
12814.131.63.128/2514.131.63.129 to 14.131.63.25414.131.63.255126
12914.131.64.0/2514.131.64.1 to 14.131.64.12614.131.64.127126
13014.131.64.128/2514.131.64.129 to 14.131.64.25414.131.64.255126
13114.131.65.0/2514.131.65.1 to 14.131.65.12614.131.65.127126
13214.131.65.128/2514.131.65.129 to 14.131.65.25414.131.65.255126
13314.131.66.0/2514.131.66.1 to 14.131.66.12614.131.66.127126
13414.131.66.128/2514.131.66.129 to 14.131.66.25414.131.66.255126
13514.131.67.0/2514.131.67.1 to 14.131.67.12614.131.67.127126
13614.131.67.128/2514.131.67.129 to 14.131.67.25414.131.67.255126
13714.131.68.0/2514.131.68.1 to 14.131.68.12614.131.68.127126
13814.131.68.128/2514.131.68.129 to 14.131.68.25414.131.68.255126
13914.131.69.0/2514.131.69.1 to 14.131.69.12614.131.69.127126
14014.131.69.128/2514.131.69.129 to 14.131.69.25414.131.69.255126
14114.131.70.0/2514.131.70.1 to 14.131.70.12614.131.70.127126
14214.131.70.128/2514.131.70.129 to 14.131.70.25414.131.70.255126
14314.131.71.0/2514.131.71.1 to 14.131.71.12614.131.71.127126
14414.131.71.128/2514.131.71.129 to 14.131.71.25414.131.71.255126
14514.131.72.0/2514.131.72.1 to 14.131.72.12614.131.72.127126
14614.131.72.128/2514.131.72.129 to 14.131.72.25414.131.72.255126
14714.131.73.0/2514.131.73.1 to 14.131.73.12614.131.73.127126
14814.131.73.128/2514.131.73.129 to 14.131.73.25414.131.73.255126
14914.131.74.0/2514.131.74.1 to 14.131.74.12614.131.74.127126
15014.131.74.128/2514.131.74.129 to 14.131.74.25414.131.74.255126
15114.131.75.0/2514.131.75.1 to 14.131.75.12614.131.75.127126
15214.131.75.128/2514.131.75.129 to 14.131.75.25414.131.75.255126
15314.131.76.0/2514.131.76.1 to 14.131.76.12614.131.76.127126
15414.131.76.128/2514.131.76.129 to 14.131.76.25414.131.76.255126
15514.131.77.0/2514.131.77.1 to 14.131.77.12614.131.77.127126
15614.131.77.128/2514.131.77.129 to 14.131.77.25414.131.77.255126
15714.131.78.0/2514.131.78.1 to 14.131.78.12614.131.78.127126
15814.131.78.128/2514.131.78.129 to 14.131.78.25414.131.78.255126
15914.131.79.0/2514.131.79.1 to 14.131.79.12614.131.79.127126
16014.131.79.128/2514.131.79.129 to 14.131.79.25414.131.79.255126
16114.131.80.0/2514.131.80.1 to 14.131.80.12614.131.80.127126
16214.131.80.128/2514.131.80.129 to 14.131.80.25414.131.80.255126
16314.131.81.0/2514.131.81.1 to 14.131.81.12614.131.81.127126
16414.131.81.128/2514.131.81.129 to 14.131.81.25414.131.81.255126
16514.131.82.0/2514.131.82.1 to 14.131.82.12614.131.82.127126
16614.131.82.128/2514.131.82.129 to 14.131.82.25414.131.82.255126
16714.131.83.0/2514.131.83.1 to 14.131.83.12614.131.83.127126
16814.131.83.128/2514.131.83.129 to 14.131.83.25414.131.83.255126
16914.131.84.0/2514.131.84.1 to 14.131.84.12614.131.84.127126
17014.131.84.128/2514.131.84.129 to 14.131.84.25414.131.84.255126
17114.131.85.0/2514.131.85.1 to 14.131.85.12614.131.85.127126
17214.131.85.128/2514.131.85.129 to 14.131.85.25414.131.85.255126
17314.131.86.0/2514.131.86.1 to 14.131.86.12614.131.86.127126
17414.131.86.128/2514.131.86.129 to 14.131.86.25414.131.86.255126
17514.131.87.0/2514.131.87.1 to 14.131.87.12614.131.87.127126
17614.131.87.128/2514.131.87.129 to 14.131.87.25414.131.87.255126
17714.131.88.0/2514.131.88.1 to 14.131.88.12614.131.88.127126
17814.131.88.128/2514.131.88.129 to 14.131.88.25414.131.88.255126
17914.131.89.0/2514.131.89.1 to 14.131.89.12614.131.89.127126
18014.131.89.128/2514.131.89.129 to 14.131.89.25414.131.89.255126
18114.131.90.0/2514.131.90.1 to 14.131.90.12614.131.90.127126
18214.131.90.128/2514.131.90.129 to 14.131.90.25414.131.90.255126
18314.131.91.0/2514.131.91.1 to 14.131.91.12614.131.91.127126
18414.131.91.128/2514.131.91.129 to 14.131.91.25414.131.91.255126
18514.131.92.0/2514.131.92.1 to 14.131.92.12614.131.92.127126
18614.131.92.128/2514.131.92.129 to 14.131.92.25414.131.92.255126
18714.131.93.0/2514.131.93.1 to 14.131.93.12614.131.93.127126
18814.131.93.128/2514.131.93.129 to 14.131.93.25414.131.93.255126
18914.131.94.0/2514.131.94.1 to 14.131.94.12614.131.94.127126
19014.131.94.128/2514.131.94.129 to 14.131.94.25414.131.94.255126
19114.131.95.0/2514.131.95.1 to 14.131.95.12614.131.95.127126
19214.131.95.128/2514.131.95.129 to 14.131.95.25414.131.95.255126
19314.131.96.0/2514.131.96.1 to 14.131.96.12614.131.96.127126
19414.131.96.128/2514.131.96.129 to 14.131.96.25414.131.96.255126
19514.131.97.0/2514.131.97.1 to 14.131.97.12614.131.97.127126
19614.131.97.128/2514.131.97.129 to 14.131.97.25414.131.97.255126
19714.131.98.0/2514.131.98.1 to 14.131.98.12614.131.98.127126
19814.131.98.128/2514.131.98.129 to 14.131.98.25414.131.98.255126
19914.131.99.0/2514.131.99.1 to 14.131.99.12614.131.99.127126
20014.131.99.128/2514.131.99.129 to 14.131.99.25414.131.99.255126
20114.131.100.0/2514.131.100.1 to 14.131.100.12614.131.100.127126
20214.131.100.128/2514.131.100.129 to 14.131.100.25414.131.100.255126
20314.131.101.0/2514.131.101.1 to 14.131.101.12614.131.101.127126
20414.131.101.128/2514.131.101.129 to 14.131.101.25414.131.101.255126
20514.131.102.0/2514.131.102.1 to 14.131.102.12614.131.102.127126
20614.131.102.128/2514.131.102.129 to 14.131.102.25414.131.102.255126
20714.131.103.0/2514.131.103.1 to 14.131.103.12614.131.103.127126
20814.131.103.128/2514.131.103.129 to 14.131.103.25414.131.103.255126
20914.131.104.0/2514.131.104.1 to 14.131.104.12614.131.104.127126
21014.131.104.128/2514.131.104.129 to 14.131.104.25414.131.104.255126
21114.131.105.0/2514.131.105.1 to 14.131.105.12614.131.105.127126
21214.131.105.128/2514.131.105.129 to 14.131.105.25414.131.105.255126
21314.131.106.0/2514.131.106.1 to 14.131.106.12614.131.106.127126
21414.131.106.128/2514.131.106.129 to 14.131.106.25414.131.106.255126
21514.131.107.0/2514.131.107.1 to 14.131.107.12614.131.107.127126
21614.131.107.128/2514.131.107.129 to 14.131.107.25414.131.107.255126
21714.131.108.0/2514.131.108.1 to 14.131.108.12614.131.108.127126
21814.131.108.128/2514.131.108.129 to 14.131.108.25414.131.108.255126
21914.131.109.0/2514.131.109.1 to 14.131.109.12614.131.109.127126
22014.131.109.128/2514.131.109.129 to 14.131.109.25414.131.109.255126
22114.131.110.0/2514.131.110.1 to 14.131.110.12614.131.110.127126
22214.131.110.128/2514.131.110.129 to 14.131.110.25414.131.110.255126
22314.131.111.0/2514.131.111.1 to 14.131.111.12614.131.111.127126
22414.131.111.128/2514.131.111.129 to 14.131.111.25414.131.111.255126
22514.131.112.0/2514.131.112.1 to 14.131.112.12614.131.112.127126
22614.131.112.128/2514.131.112.129 to 14.131.112.25414.131.112.255126
22714.131.113.0/2514.131.113.1 to 14.131.113.12614.131.113.127126
22814.131.113.128/2514.131.113.129 to 14.131.113.25414.131.113.255126
22914.131.114.0/2514.131.114.1 to 14.131.114.12614.131.114.127126
23014.131.114.128/2514.131.114.129 to 14.131.114.25414.131.114.255126
23114.131.115.0/2514.131.115.1 to 14.131.115.12614.131.115.127126
23214.131.115.128/2514.131.115.129 to 14.131.115.25414.131.115.255126
23314.131.116.0/2514.131.116.1 to 14.131.116.12614.131.116.127126
23414.131.116.128/2514.131.116.129 to 14.131.116.25414.131.116.255126
23514.131.117.0/2514.131.117.1 to 14.131.117.12614.131.117.127126
23614.131.117.128/2514.131.117.129 to 14.131.117.25414.131.117.255126
23714.131.118.0/2514.131.118.1 to 14.131.118.12614.131.118.127126
23814.131.118.128/2514.131.118.129 to 14.131.118.25414.131.118.255126
23914.131.119.0/2514.131.119.1 to 14.131.119.12614.131.119.127126
24014.131.119.128/2514.131.119.129 to 14.131.119.25414.131.119.255126
24114.131.120.0/2514.131.120.1 to 14.131.120.12614.131.120.127126
24214.131.120.128/2514.131.120.129 to 14.131.120.25414.131.120.255126
24314.131.121.0/2514.131.121.1 to 14.131.121.12614.131.121.127126
24414.131.121.128/2514.131.121.129 to 14.131.121.25414.131.121.255126
24514.131.122.0/2514.131.122.1 to 14.131.122.12614.131.122.127126
24614.131.122.128/2514.131.122.129 to 14.131.122.25414.131.122.255126
24714.131.123.0/2514.131.123.1 to 14.131.123.12614.131.123.127126
24814.131.123.128/2514.131.123.129 to 14.131.123.25414.131.123.255126
24914.131.124.0/2514.131.124.1 to 14.131.124.12614.131.124.127126
25014.131.124.128/2514.131.124.129 to 14.131.124.25414.131.124.255126
25114.131.125.0/2514.131.125.1 to 14.131.125.12614.131.125.127126
25214.131.125.128/2514.131.125.129 to 14.131.125.25414.131.125.255126
25314.131.126.0/2514.131.126.1 to 14.131.126.12614.131.126.127126
25414.131.126.128/2514.131.126.129 to 14.131.126.25414.131.126.255126
25514.131.127.0/2514.131.127.1 to 14.131.127.12614.131.127.127126
25614.131.127.128/2514.131.127.129 to 14.131.127.25414.131.127.255126

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.