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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.

Network14.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
14.0.0.0
Broadcast address
15.255.255.255
First usable
14.0.0.1
Last usable
15.255.255.254
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 0E000000 · Integer 234881024 to 268435455
Reverse DNS zones
14.in-addr.arpa
15.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
Address00001110.00000000.00000000.0000000014.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network00001110.00000000.00000000.0000000014.0.0.0
Broadcast00001111.11111111.11111111.1111111115.255.255.255
Split into smaller subnets/16
/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)

14.0.0.0/7 makes 512 subnets of /16; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
114.0.0.0/1614.0.0.1 to 14.0.255.25414.0.255.25565,534
214.1.0.0/1614.1.0.1 to 14.1.255.25414.1.255.25565,534
314.2.0.0/1614.2.0.1 to 14.2.255.25414.2.255.25565,534
414.3.0.0/1614.3.0.1 to 14.3.255.25414.3.255.25565,534
514.4.0.0/1614.4.0.1 to 14.4.255.25414.4.255.25565,534
614.5.0.0/1614.5.0.1 to 14.5.255.25414.5.255.25565,534
714.6.0.0/1614.6.0.1 to 14.6.255.25414.6.255.25565,534
814.7.0.0/1614.7.0.1 to 14.7.255.25414.7.255.25565,534
914.8.0.0/1614.8.0.1 to 14.8.255.25414.8.255.25565,534
1014.9.0.0/1614.9.0.1 to 14.9.255.25414.9.255.25565,534
1114.10.0.0/1614.10.0.1 to 14.10.255.25414.10.255.25565,534
1214.11.0.0/1614.11.0.1 to 14.11.255.25414.11.255.25565,534
1314.12.0.0/1614.12.0.1 to 14.12.255.25414.12.255.25565,534
1414.13.0.0/1614.13.0.1 to 14.13.255.25414.13.255.25565,534
1514.14.0.0/1614.14.0.1 to 14.14.255.25414.14.255.25565,534
1614.15.0.0/1614.15.0.1 to 14.15.255.25414.15.255.25565,534
1714.16.0.0/1614.16.0.1 to 14.16.255.25414.16.255.25565,534
1814.17.0.0/1614.17.0.1 to 14.17.255.25414.17.255.25565,534
1914.18.0.0/1614.18.0.1 to 14.18.255.25414.18.255.25565,534
2014.19.0.0/1614.19.0.1 to 14.19.255.25414.19.255.25565,534
2114.20.0.0/1614.20.0.1 to 14.20.255.25414.20.255.25565,534
2214.21.0.0/1614.21.0.1 to 14.21.255.25414.21.255.25565,534
2314.22.0.0/1614.22.0.1 to 14.22.255.25414.22.255.25565,534
2414.23.0.0/1614.23.0.1 to 14.23.255.25414.23.255.25565,534
2514.24.0.0/1614.24.0.1 to 14.24.255.25414.24.255.25565,534
2614.25.0.0/1614.25.0.1 to 14.25.255.25414.25.255.25565,534
2714.26.0.0/1614.26.0.1 to 14.26.255.25414.26.255.25565,534
2814.27.0.0/1614.27.0.1 to 14.27.255.25414.27.255.25565,534
2914.28.0.0/1614.28.0.1 to 14.28.255.25414.28.255.25565,534
3014.29.0.0/1614.29.0.1 to 14.29.255.25414.29.255.25565,534
3114.30.0.0/1614.30.0.1 to 14.30.255.25414.30.255.25565,534
3214.31.0.0/1614.31.0.1 to 14.31.255.25414.31.255.25565,534
3314.32.0.0/1614.32.0.1 to 14.32.255.25414.32.255.25565,534
3414.33.0.0/1614.33.0.1 to 14.33.255.25414.33.255.25565,534
3514.34.0.0/1614.34.0.1 to 14.34.255.25414.34.255.25565,534
3614.35.0.0/1614.35.0.1 to 14.35.255.25414.35.255.25565,534
3714.36.0.0/1614.36.0.1 to 14.36.255.25414.36.255.25565,534
3814.37.0.0/1614.37.0.1 to 14.37.255.25414.37.255.25565,534
3914.38.0.0/1614.38.0.1 to 14.38.255.25414.38.255.25565,534
4014.39.0.0/1614.39.0.1 to 14.39.255.25414.39.255.25565,534
4114.40.0.0/1614.40.0.1 to 14.40.255.25414.40.255.25565,534
4214.41.0.0/1614.41.0.1 to 14.41.255.25414.41.255.25565,534
4314.42.0.0/1614.42.0.1 to 14.42.255.25414.42.255.25565,534
4414.43.0.0/1614.43.0.1 to 14.43.255.25414.43.255.25565,534
4514.44.0.0/1614.44.0.1 to 14.44.255.25414.44.255.25565,534
4614.45.0.0/1614.45.0.1 to 14.45.255.25414.45.255.25565,534
4714.46.0.0/1614.46.0.1 to 14.46.255.25414.46.255.25565,534
4814.47.0.0/1614.47.0.1 to 14.47.255.25414.47.255.25565,534
4914.48.0.0/1614.48.0.1 to 14.48.255.25414.48.255.25565,534
5014.49.0.0/1614.49.0.1 to 14.49.255.25414.49.255.25565,534
5114.50.0.0/1614.50.0.1 to 14.50.255.25414.50.255.25565,534
5214.51.0.0/1614.51.0.1 to 14.51.255.25414.51.255.25565,534
5314.52.0.0/1614.52.0.1 to 14.52.255.25414.52.255.25565,534
5414.53.0.0/1614.53.0.1 to 14.53.255.25414.53.255.25565,534
5514.54.0.0/1614.54.0.1 to 14.54.255.25414.54.255.25565,534
5614.55.0.0/1614.55.0.1 to 14.55.255.25414.55.255.25565,534
5714.56.0.0/1614.56.0.1 to 14.56.255.25414.56.255.25565,534
5814.57.0.0/1614.57.0.1 to 14.57.255.25414.57.255.25565,534
5914.58.0.0/1614.58.0.1 to 14.58.255.25414.58.255.25565,534
6014.59.0.0/1614.59.0.1 to 14.59.255.25414.59.255.25565,534
6114.60.0.0/1614.60.0.1 to 14.60.255.25414.60.255.25565,534
6214.61.0.0/1614.61.0.1 to 14.61.255.25414.61.255.25565,534
6314.62.0.0/1614.62.0.1 to 14.62.255.25414.62.255.25565,534
6414.63.0.0/1614.63.0.1 to 14.63.255.25414.63.255.25565,534
6514.64.0.0/1614.64.0.1 to 14.64.255.25414.64.255.25565,534
6614.65.0.0/1614.65.0.1 to 14.65.255.25414.65.255.25565,534
6714.66.0.0/1614.66.0.1 to 14.66.255.25414.66.255.25565,534
6814.67.0.0/1614.67.0.1 to 14.67.255.25414.67.255.25565,534
6914.68.0.0/1614.68.0.1 to 14.68.255.25414.68.255.25565,534
7014.69.0.0/1614.69.0.1 to 14.69.255.25414.69.255.25565,534
7114.70.0.0/1614.70.0.1 to 14.70.255.25414.70.255.25565,534
7214.71.0.0/1614.71.0.1 to 14.71.255.25414.71.255.25565,534
7314.72.0.0/1614.72.0.1 to 14.72.255.25414.72.255.25565,534
7414.73.0.0/1614.73.0.1 to 14.73.255.25414.73.255.25565,534
7514.74.0.0/1614.74.0.1 to 14.74.255.25414.74.255.25565,534
7614.75.0.0/1614.75.0.1 to 14.75.255.25414.75.255.25565,534
7714.76.0.0/1614.76.0.1 to 14.76.255.25414.76.255.25565,534
7814.77.0.0/1614.77.0.1 to 14.77.255.25414.77.255.25565,534
7914.78.0.0/1614.78.0.1 to 14.78.255.25414.78.255.25565,534
8014.79.0.0/1614.79.0.1 to 14.79.255.25414.79.255.25565,534
8114.80.0.0/1614.80.0.1 to 14.80.255.25414.80.255.25565,534
8214.81.0.0/1614.81.0.1 to 14.81.255.25414.81.255.25565,534
8314.82.0.0/1614.82.0.1 to 14.82.255.25414.82.255.25565,534
8414.83.0.0/1614.83.0.1 to 14.83.255.25414.83.255.25565,534
8514.84.0.0/1614.84.0.1 to 14.84.255.25414.84.255.25565,534
8614.85.0.0/1614.85.0.1 to 14.85.255.25414.85.255.25565,534
8714.86.0.0/1614.86.0.1 to 14.86.255.25414.86.255.25565,534
8814.87.0.0/1614.87.0.1 to 14.87.255.25414.87.255.25565,534
8914.88.0.0/1614.88.0.1 to 14.88.255.25414.88.255.25565,534
9014.89.0.0/1614.89.0.1 to 14.89.255.25414.89.255.25565,534
9114.90.0.0/1614.90.0.1 to 14.90.255.25414.90.255.25565,534
9214.91.0.0/1614.91.0.1 to 14.91.255.25414.91.255.25565,534
9314.92.0.0/1614.92.0.1 to 14.92.255.25414.92.255.25565,534
9414.93.0.0/1614.93.0.1 to 14.93.255.25414.93.255.25565,534
9514.94.0.0/1614.94.0.1 to 14.94.255.25414.94.255.25565,534
9614.95.0.0/1614.95.0.1 to 14.95.255.25414.95.255.25565,534
9714.96.0.0/1614.96.0.1 to 14.96.255.25414.96.255.25565,534
9814.97.0.0/1614.97.0.1 to 14.97.255.25414.97.255.25565,534
9914.98.0.0/1614.98.0.1 to 14.98.255.25414.98.255.25565,534
10014.99.0.0/1614.99.0.1 to 14.99.255.25414.99.255.25565,534
10114.100.0.0/1614.100.0.1 to 14.100.255.25414.100.255.25565,534
10214.101.0.0/1614.101.0.1 to 14.101.255.25414.101.255.25565,534
10314.102.0.0/1614.102.0.1 to 14.102.255.25414.102.255.25565,534
10414.103.0.0/1614.103.0.1 to 14.103.255.25414.103.255.25565,534
10514.104.0.0/1614.104.0.1 to 14.104.255.25414.104.255.25565,534
10614.105.0.0/1614.105.0.1 to 14.105.255.25414.105.255.25565,534
10714.106.0.0/1614.106.0.1 to 14.106.255.25414.106.255.25565,534
10814.107.0.0/1614.107.0.1 to 14.107.255.25414.107.255.25565,534
10914.108.0.0/1614.108.0.1 to 14.108.255.25414.108.255.25565,534
11014.109.0.0/1614.109.0.1 to 14.109.255.25414.109.255.25565,534
11114.110.0.0/1614.110.0.1 to 14.110.255.25414.110.255.25565,534
11214.111.0.0/1614.111.0.1 to 14.111.255.25414.111.255.25565,534
11314.112.0.0/1614.112.0.1 to 14.112.255.25414.112.255.25565,534
11414.113.0.0/1614.113.0.1 to 14.113.255.25414.113.255.25565,534
11514.114.0.0/1614.114.0.1 to 14.114.255.25414.114.255.25565,534
11614.115.0.0/1614.115.0.1 to 14.115.255.25414.115.255.25565,534
11714.116.0.0/1614.116.0.1 to 14.116.255.25414.116.255.25565,534
11814.117.0.0/1614.117.0.1 to 14.117.255.25414.117.255.25565,534
11914.118.0.0/1614.118.0.1 to 14.118.255.25414.118.255.25565,534
12014.119.0.0/1614.119.0.1 to 14.119.255.25414.119.255.25565,534
12114.120.0.0/1614.120.0.1 to 14.120.255.25414.120.255.25565,534
12214.121.0.0/1614.121.0.1 to 14.121.255.25414.121.255.25565,534
12314.122.0.0/1614.122.0.1 to 14.122.255.25414.122.255.25565,534
12414.123.0.0/1614.123.0.1 to 14.123.255.25414.123.255.25565,534
12514.124.0.0/1614.124.0.1 to 14.124.255.25414.124.255.25565,534
12614.125.0.0/1614.125.0.1 to 14.125.255.25414.125.255.25565,534
12714.126.0.0/1614.126.0.1 to 14.126.255.25414.126.255.25565,534
12814.127.0.0/1614.127.0.1 to 14.127.255.25414.127.255.25565,534
12914.128.0.0/1614.128.0.1 to 14.128.255.25414.128.255.25565,534
13014.129.0.0/1614.129.0.1 to 14.129.255.25414.129.255.25565,534
13114.130.0.0/1614.130.0.1 to 14.130.255.25414.130.255.25565,534
13214.131.0.0/1614.131.0.1 to 14.131.255.25414.131.255.25565,534
13314.132.0.0/1614.132.0.1 to 14.132.255.25414.132.255.25565,534
13414.133.0.0/1614.133.0.1 to 14.133.255.25414.133.255.25565,534
13514.134.0.0/1614.134.0.1 to 14.134.255.25414.134.255.25565,534
13614.135.0.0/1614.135.0.1 to 14.135.255.25414.135.255.25565,534
13714.136.0.0/1614.136.0.1 to 14.136.255.25414.136.255.25565,534
13814.137.0.0/1614.137.0.1 to 14.137.255.25414.137.255.25565,534
13914.138.0.0/1614.138.0.1 to 14.138.255.25414.138.255.25565,534
14014.139.0.0/1614.139.0.1 to 14.139.255.25414.139.255.25565,534
14114.140.0.0/1614.140.0.1 to 14.140.255.25414.140.255.25565,534
14214.141.0.0/1614.141.0.1 to 14.141.255.25414.141.255.25565,534
14314.142.0.0/1614.142.0.1 to 14.142.255.25414.142.255.25565,534
14414.143.0.0/1614.143.0.1 to 14.143.255.25414.143.255.25565,534
14514.144.0.0/1614.144.0.1 to 14.144.255.25414.144.255.25565,534
14614.145.0.0/1614.145.0.1 to 14.145.255.25414.145.255.25565,534
14714.146.0.0/1614.146.0.1 to 14.146.255.25414.146.255.25565,534
14814.147.0.0/1614.147.0.1 to 14.147.255.25414.147.255.25565,534
14914.148.0.0/1614.148.0.1 to 14.148.255.25414.148.255.25565,534
15014.149.0.0/1614.149.0.1 to 14.149.255.25414.149.255.25565,534
15114.150.0.0/1614.150.0.1 to 14.150.255.25414.150.255.25565,534
15214.151.0.0/1614.151.0.1 to 14.151.255.25414.151.255.25565,534
15314.152.0.0/1614.152.0.1 to 14.152.255.25414.152.255.25565,534
15414.153.0.0/1614.153.0.1 to 14.153.255.25414.153.255.25565,534
15514.154.0.0/1614.154.0.1 to 14.154.255.25414.154.255.25565,534
15614.155.0.0/1614.155.0.1 to 14.155.255.25414.155.255.25565,534
15714.156.0.0/1614.156.0.1 to 14.156.255.25414.156.255.25565,534
15814.157.0.0/1614.157.0.1 to 14.157.255.25414.157.255.25565,534
15914.158.0.0/1614.158.0.1 to 14.158.255.25414.158.255.25565,534
16014.159.0.0/1614.159.0.1 to 14.159.255.25414.159.255.25565,534
16114.160.0.0/1614.160.0.1 to 14.160.255.25414.160.255.25565,534
16214.161.0.0/1614.161.0.1 to 14.161.255.25414.161.255.25565,534
16314.162.0.0/1614.162.0.1 to 14.162.255.25414.162.255.25565,534
16414.163.0.0/1614.163.0.1 to 14.163.255.25414.163.255.25565,534
16514.164.0.0/1614.164.0.1 to 14.164.255.25414.164.255.25565,534
16614.165.0.0/1614.165.0.1 to 14.165.255.25414.165.255.25565,534
16714.166.0.0/1614.166.0.1 to 14.166.255.25414.166.255.25565,534
16814.167.0.0/1614.167.0.1 to 14.167.255.25414.167.255.25565,534
16914.168.0.0/1614.168.0.1 to 14.168.255.25414.168.255.25565,534
17014.169.0.0/1614.169.0.1 to 14.169.255.25414.169.255.25565,534
17114.170.0.0/1614.170.0.1 to 14.170.255.25414.170.255.25565,534
17214.171.0.0/1614.171.0.1 to 14.171.255.25414.171.255.25565,534
17314.172.0.0/1614.172.0.1 to 14.172.255.25414.172.255.25565,534
17414.173.0.0/1614.173.0.1 to 14.173.255.25414.173.255.25565,534
17514.174.0.0/1614.174.0.1 to 14.174.255.25414.174.255.25565,534
17614.175.0.0/1614.175.0.1 to 14.175.255.25414.175.255.25565,534
17714.176.0.0/1614.176.0.1 to 14.176.255.25414.176.255.25565,534
17814.177.0.0/1614.177.0.1 to 14.177.255.25414.177.255.25565,534
17914.178.0.0/1614.178.0.1 to 14.178.255.25414.178.255.25565,534
18014.179.0.0/1614.179.0.1 to 14.179.255.25414.179.255.25565,534
18114.180.0.0/1614.180.0.1 to 14.180.255.25414.180.255.25565,534
18214.181.0.0/1614.181.0.1 to 14.181.255.25414.181.255.25565,534
18314.182.0.0/1614.182.0.1 to 14.182.255.25414.182.255.25565,534
18414.183.0.0/1614.183.0.1 to 14.183.255.25414.183.255.25565,534
18514.184.0.0/1614.184.0.1 to 14.184.255.25414.184.255.25565,534
18614.185.0.0/1614.185.0.1 to 14.185.255.25414.185.255.25565,534
18714.186.0.0/1614.186.0.1 to 14.186.255.25414.186.255.25565,534
18814.187.0.0/1614.187.0.1 to 14.187.255.25414.187.255.25565,534
18914.188.0.0/1614.188.0.1 to 14.188.255.25414.188.255.25565,534
19014.189.0.0/1614.189.0.1 to 14.189.255.25414.189.255.25565,534
19114.190.0.0/1614.190.0.1 to 14.190.255.25414.190.255.25565,534
19214.191.0.0/1614.191.0.1 to 14.191.255.25414.191.255.25565,534
19314.192.0.0/1614.192.0.1 to 14.192.255.25414.192.255.25565,534
19414.193.0.0/1614.193.0.1 to 14.193.255.25414.193.255.25565,534
19514.194.0.0/1614.194.0.1 to 14.194.255.25414.194.255.25565,534
19614.195.0.0/1614.195.0.1 to 14.195.255.25414.195.255.25565,534
19714.196.0.0/1614.196.0.1 to 14.196.255.25414.196.255.25565,534
19814.197.0.0/1614.197.0.1 to 14.197.255.25414.197.255.25565,534
19914.198.0.0/1614.198.0.1 to 14.198.255.25414.198.255.25565,534
20014.199.0.0/1614.199.0.1 to 14.199.255.25414.199.255.25565,534
20114.200.0.0/1614.200.0.1 to 14.200.255.25414.200.255.25565,534
20214.201.0.0/1614.201.0.1 to 14.201.255.25414.201.255.25565,534
20314.202.0.0/1614.202.0.1 to 14.202.255.25414.202.255.25565,534
20414.203.0.0/1614.203.0.1 to 14.203.255.25414.203.255.25565,534
20514.204.0.0/1614.204.0.1 to 14.204.255.25414.204.255.25565,534
20614.205.0.0/1614.205.0.1 to 14.205.255.25414.205.255.25565,534
20714.206.0.0/1614.206.0.1 to 14.206.255.25414.206.255.25565,534
20814.207.0.0/1614.207.0.1 to 14.207.255.25414.207.255.25565,534
20914.208.0.0/1614.208.0.1 to 14.208.255.25414.208.255.25565,534
21014.209.0.0/1614.209.0.1 to 14.209.255.25414.209.255.25565,534
21114.210.0.0/1614.210.0.1 to 14.210.255.25414.210.255.25565,534
21214.211.0.0/1614.211.0.1 to 14.211.255.25414.211.255.25565,534
21314.212.0.0/1614.212.0.1 to 14.212.255.25414.212.255.25565,534
21414.213.0.0/1614.213.0.1 to 14.213.255.25414.213.255.25565,534
21514.214.0.0/1614.214.0.1 to 14.214.255.25414.214.255.25565,534
21614.215.0.0/1614.215.0.1 to 14.215.255.25414.215.255.25565,534
21714.216.0.0/1614.216.0.1 to 14.216.255.25414.216.255.25565,534
21814.217.0.0/1614.217.0.1 to 14.217.255.25414.217.255.25565,534
21914.218.0.0/1614.218.0.1 to 14.218.255.25414.218.255.25565,534
22014.219.0.0/1614.219.0.1 to 14.219.255.25414.219.255.25565,534
22114.220.0.0/1614.220.0.1 to 14.220.255.25414.220.255.25565,534
22214.221.0.0/1614.221.0.1 to 14.221.255.25414.221.255.25565,534
22314.222.0.0/1614.222.0.1 to 14.222.255.25414.222.255.25565,534
22414.223.0.0/1614.223.0.1 to 14.223.255.25414.223.255.25565,534
22514.224.0.0/1614.224.0.1 to 14.224.255.25414.224.255.25565,534
22614.225.0.0/1614.225.0.1 to 14.225.255.25414.225.255.25565,534
22714.226.0.0/1614.226.0.1 to 14.226.255.25414.226.255.25565,534
22814.227.0.0/1614.227.0.1 to 14.227.255.25414.227.255.25565,534
22914.228.0.0/1614.228.0.1 to 14.228.255.25414.228.255.25565,534
23014.229.0.0/1614.229.0.1 to 14.229.255.25414.229.255.25565,534
23114.230.0.0/1614.230.0.1 to 14.230.255.25414.230.255.25565,534
23214.231.0.0/1614.231.0.1 to 14.231.255.25414.231.255.25565,534
23314.232.0.0/1614.232.0.1 to 14.232.255.25414.232.255.25565,534
23414.233.0.0/1614.233.0.1 to 14.233.255.25414.233.255.25565,534
23514.234.0.0/1614.234.0.1 to 14.234.255.25414.234.255.25565,534
23614.235.0.0/1614.235.0.1 to 14.235.255.25414.235.255.25565,534
23714.236.0.0/1614.236.0.1 to 14.236.255.25414.236.255.25565,534
23814.237.0.0/1614.237.0.1 to 14.237.255.25414.237.255.25565,534
23914.238.0.0/1614.238.0.1 to 14.238.255.25414.238.255.25565,534
24014.239.0.0/1614.239.0.1 to 14.239.255.25414.239.255.25565,534
24114.240.0.0/1614.240.0.1 to 14.240.255.25414.240.255.25565,534
24214.241.0.0/1614.241.0.1 to 14.241.255.25414.241.255.25565,534
24314.242.0.0/1614.242.0.1 to 14.242.255.25414.242.255.25565,534
24414.243.0.0/1614.243.0.1 to 14.243.255.25414.243.255.25565,534
24514.244.0.0/1614.244.0.1 to 14.244.255.25414.244.255.25565,534
24614.245.0.0/1614.245.0.1 to 14.245.255.25414.245.255.25565,534
24714.246.0.0/1614.246.0.1 to 14.246.255.25414.246.255.25565,534
24814.247.0.0/1614.247.0.1 to 14.247.255.25414.247.255.25565,534
24914.248.0.0/1614.248.0.1 to 14.248.255.25414.248.255.25565,534
25014.249.0.0/1614.249.0.1 to 14.249.255.25414.249.255.25565,534
25114.250.0.0/1614.250.0.1 to 14.250.255.25414.250.255.25565,534
25214.251.0.0/1614.251.0.1 to 14.251.255.25414.251.255.25565,534
25314.252.0.0/1614.252.0.1 to 14.252.255.25414.252.255.25565,534
25414.253.0.0/1614.253.0.1 to 14.253.255.25414.253.255.25565,534
25514.254.0.0/1614.254.0.1 to 14.254.255.25414.254.255.25565,534
25614.255.0.0/1614.255.0.1 to 14.255.255.25414.255.255.25565,534

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.