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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.

Network14.0.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
14.0.0.0
Broadcast address
14.7.255.255
First usable
14.0.0.1
Last usable
14.7.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 0E000000 · Integer 234881024 to 235405311
Reverse DNS zones
0.14.in-addr.arpa
1.14.in-addr.arpa
2.14.in-addr.arpa
3.14.in-addr.arpa
4.14.in-addr.arpa
5.14.in-addr.arpa
6.14.in-addr.arpa
7.14.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00001110.00000000.00000000.0000000014.0.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network00001110.00000000.00000000.0000000014.0.0.0
Broadcast00001110.00000111.11111111.1111111114.7.255.255
Split into smaller subnets/23
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

14.0.0.0/13 makes 1,024 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
114.0.0.0/2314.0.0.1 to 14.0.1.25414.0.1.255510
214.0.2.0/2314.0.2.1 to 14.0.3.25414.0.3.255510
314.0.4.0/2314.0.4.1 to 14.0.5.25414.0.5.255510
414.0.6.0/2314.0.6.1 to 14.0.7.25414.0.7.255510
514.0.8.0/2314.0.8.1 to 14.0.9.25414.0.9.255510
614.0.10.0/2314.0.10.1 to 14.0.11.25414.0.11.255510
714.0.12.0/2314.0.12.1 to 14.0.13.25414.0.13.255510
814.0.14.0/2314.0.14.1 to 14.0.15.25414.0.15.255510
914.0.16.0/2314.0.16.1 to 14.0.17.25414.0.17.255510
1014.0.18.0/2314.0.18.1 to 14.0.19.25414.0.19.255510
1114.0.20.0/2314.0.20.1 to 14.0.21.25414.0.21.255510
1214.0.22.0/2314.0.22.1 to 14.0.23.25414.0.23.255510
1314.0.24.0/2314.0.24.1 to 14.0.25.25414.0.25.255510
1414.0.26.0/2314.0.26.1 to 14.0.27.25414.0.27.255510
1514.0.28.0/2314.0.28.1 to 14.0.29.25414.0.29.255510
1614.0.30.0/2314.0.30.1 to 14.0.31.25414.0.31.255510
1714.0.32.0/2314.0.32.1 to 14.0.33.25414.0.33.255510
1814.0.34.0/2314.0.34.1 to 14.0.35.25414.0.35.255510
1914.0.36.0/2314.0.36.1 to 14.0.37.25414.0.37.255510
2014.0.38.0/2314.0.38.1 to 14.0.39.25414.0.39.255510
2114.0.40.0/2314.0.40.1 to 14.0.41.25414.0.41.255510
2214.0.42.0/2314.0.42.1 to 14.0.43.25414.0.43.255510
2314.0.44.0/2314.0.44.1 to 14.0.45.25414.0.45.255510
2414.0.46.0/2314.0.46.1 to 14.0.47.25414.0.47.255510
2514.0.48.0/2314.0.48.1 to 14.0.49.25414.0.49.255510
2614.0.50.0/2314.0.50.1 to 14.0.51.25414.0.51.255510
2714.0.52.0/2314.0.52.1 to 14.0.53.25414.0.53.255510
2814.0.54.0/2314.0.54.1 to 14.0.55.25414.0.55.255510
2914.0.56.0/2314.0.56.1 to 14.0.57.25414.0.57.255510
3014.0.58.0/2314.0.58.1 to 14.0.59.25414.0.59.255510
3114.0.60.0/2314.0.60.1 to 14.0.61.25414.0.61.255510
3214.0.62.0/2314.0.62.1 to 14.0.63.25414.0.63.255510
3314.0.64.0/2314.0.64.1 to 14.0.65.25414.0.65.255510
3414.0.66.0/2314.0.66.1 to 14.0.67.25414.0.67.255510
3514.0.68.0/2314.0.68.1 to 14.0.69.25414.0.69.255510
3614.0.70.0/2314.0.70.1 to 14.0.71.25414.0.71.255510
3714.0.72.0/2314.0.72.1 to 14.0.73.25414.0.73.255510
3814.0.74.0/2314.0.74.1 to 14.0.75.25414.0.75.255510
3914.0.76.0/2314.0.76.1 to 14.0.77.25414.0.77.255510
4014.0.78.0/2314.0.78.1 to 14.0.79.25414.0.79.255510
4114.0.80.0/2314.0.80.1 to 14.0.81.25414.0.81.255510
4214.0.82.0/2314.0.82.1 to 14.0.83.25414.0.83.255510
4314.0.84.0/2314.0.84.1 to 14.0.85.25414.0.85.255510
4414.0.86.0/2314.0.86.1 to 14.0.87.25414.0.87.255510
4514.0.88.0/2314.0.88.1 to 14.0.89.25414.0.89.255510
4614.0.90.0/2314.0.90.1 to 14.0.91.25414.0.91.255510
4714.0.92.0/2314.0.92.1 to 14.0.93.25414.0.93.255510
4814.0.94.0/2314.0.94.1 to 14.0.95.25414.0.95.255510
4914.0.96.0/2314.0.96.1 to 14.0.97.25414.0.97.255510
5014.0.98.0/2314.0.98.1 to 14.0.99.25414.0.99.255510
5114.0.100.0/2314.0.100.1 to 14.0.101.25414.0.101.255510
5214.0.102.0/2314.0.102.1 to 14.0.103.25414.0.103.255510
5314.0.104.0/2314.0.104.1 to 14.0.105.25414.0.105.255510
5414.0.106.0/2314.0.106.1 to 14.0.107.25414.0.107.255510
5514.0.108.0/2314.0.108.1 to 14.0.109.25414.0.109.255510
5614.0.110.0/2314.0.110.1 to 14.0.111.25414.0.111.255510
5714.0.112.0/2314.0.112.1 to 14.0.113.25414.0.113.255510
5814.0.114.0/2314.0.114.1 to 14.0.115.25414.0.115.255510
5914.0.116.0/2314.0.116.1 to 14.0.117.25414.0.117.255510
6014.0.118.0/2314.0.118.1 to 14.0.119.25414.0.119.255510
6114.0.120.0/2314.0.120.1 to 14.0.121.25414.0.121.255510
6214.0.122.0/2314.0.122.1 to 14.0.123.25414.0.123.255510
6314.0.124.0/2314.0.124.1 to 14.0.125.25414.0.125.255510
6414.0.126.0/2314.0.126.1 to 14.0.127.25414.0.127.255510
6514.0.128.0/2314.0.128.1 to 14.0.129.25414.0.129.255510
6614.0.130.0/2314.0.130.1 to 14.0.131.25414.0.131.255510
6714.0.132.0/2314.0.132.1 to 14.0.133.25414.0.133.255510
6814.0.134.0/2314.0.134.1 to 14.0.135.25414.0.135.255510
6914.0.136.0/2314.0.136.1 to 14.0.137.25414.0.137.255510
7014.0.138.0/2314.0.138.1 to 14.0.139.25414.0.139.255510
7114.0.140.0/2314.0.140.1 to 14.0.141.25414.0.141.255510
7214.0.142.0/2314.0.142.1 to 14.0.143.25414.0.143.255510
7314.0.144.0/2314.0.144.1 to 14.0.145.25414.0.145.255510
7414.0.146.0/2314.0.146.1 to 14.0.147.25414.0.147.255510
7514.0.148.0/2314.0.148.1 to 14.0.149.25414.0.149.255510
7614.0.150.0/2314.0.150.1 to 14.0.151.25414.0.151.255510
7714.0.152.0/2314.0.152.1 to 14.0.153.25414.0.153.255510
7814.0.154.0/2314.0.154.1 to 14.0.155.25414.0.155.255510
7914.0.156.0/2314.0.156.1 to 14.0.157.25414.0.157.255510
8014.0.158.0/2314.0.158.1 to 14.0.159.25414.0.159.255510
8114.0.160.0/2314.0.160.1 to 14.0.161.25414.0.161.255510
8214.0.162.0/2314.0.162.1 to 14.0.163.25414.0.163.255510
8314.0.164.0/2314.0.164.1 to 14.0.165.25414.0.165.255510
8414.0.166.0/2314.0.166.1 to 14.0.167.25414.0.167.255510
8514.0.168.0/2314.0.168.1 to 14.0.169.25414.0.169.255510
8614.0.170.0/2314.0.170.1 to 14.0.171.25414.0.171.255510
8714.0.172.0/2314.0.172.1 to 14.0.173.25414.0.173.255510
8814.0.174.0/2314.0.174.1 to 14.0.175.25414.0.175.255510
8914.0.176.0/2314.0.176.1 to 14.0.177.25414.0.177.255510
9014.0.178.0/2314.0.178.1 to 14.0.179.25414.0.179.255510
9114.0.180.0/2314.0.180.1 to 14.0.181.25414.0.181.255510
9214.0.182.0/2314.0.182.1 to 14.0.183.25414.0.183.255510
9314.0.184.0/2314.0.184.1 to 14.0.185.25414.0.185.255510
9414.0.186.0/2314.0.186.1 to 14.0.187.25414.0.187.255510
9514.0.188.0/2314.0.188.1 to 14.0.189.25414.0.189.255510
9614.0.190.0/2314.0.190.1 to 14.0.191.25414.0.191.255510
9714.0.192.0/2314.0.192.1 to 14.0.193.25414.0.193.255510
9814.0.194.0/2314.0.194.1 to 14.0.195.25414.0.195.255510
9914.0.196.0/2314.0.196.1 to 14.0.197.25414.0.197.255510
10014.0.198.0/2314.0.198.1 to 14.0.199.25414.0.199.255510
10114.0.200.0/2314.0.200.1 to 14.0.201.25414.0.201.255510
10214.0.202.0/2314.0.202.1 to 14.0.203.25414.0.203.255510
10314.0.204.0/2314.0.204.1 to 14.0.205.25414.0.205.255510
10414.0.206.0/2314.0.206.1 to 14.0.207.25414.0.207.255510
10514.0.208.0/2314.0.208.1 to 14.0.209.25414.0.209.255510
10614.0.210.0/2314.0.210.1 to 14.0.211.25414.0.211.255510
10714.0.212.0/2314.0.212.1 to 14.0.213.25414.0.213.255510
10814.0.214.0/2314.0.214.1 to 14.0.215.25414.0.215.255510
10914.0.216.0/2314.0.216.1 to 14.0.217.25414.0.217.255510
11014.0.218.0/2314.0.218.1 to 14.0.219.25414.0.219.255510
11114.0.220.0/2314.0.220.1 to 14.0.221.25414.0.221.255510
11214.0.222.0/2314.0.222.1 to 14.0.223.25414.0.223.255510
11314.0.224.0/2314.0.224.1 to 14.0.225.25414.0.225.255510
11414.0.226.0/2314.0.226.1 to 14.0.227.25414.0.227.255510
11514.0.228.0/2314.0.228.1 to 14.0.229.25414.0.229.255510
11614.0.230.0/2314.0.230.1 to 14.0.231.25414.0.231.255510
11714.0.232.0/2314.0.232.1 to 14.0.233.25414.0.233.255510
11814.0.234.0/2314.0.234.1 to 14.0.235.25414.0.235.255510
11914.0.236.0/2314.0.236.1 to 14.0.237.25414.0.237.255510
12014.0.238.0/2314.0.238.1 to 14.0.239.25414.0.239.255510
12114.0.240.0/2314.0.240.1 to 14.0.241.25414.0.241.255510
12214.0.242.0/2314.0.242.1 to 14.0.243.25414.0.243.255510
12314.0.244.0/2314.0.244.1 to 14.0.245.25414.0.245.255510
12414.0.246.0/2314.0.246.1 to 14.0.247.25414.0.247.255510
12514.0.248.0/2314.0.248.1 to 14.0.249.25414.0.249.255510
12614.0.250.0/2314.0.250.1 to 14.0.251.25414.0.251.255510
12714.0.252.0/2314.0.252.1 to 14.0.253.25414.0.253.255510
12814.0.254.0/2314.0.254.1 to 14.0.255.25414.0.255.255510
12914.1.0.0/2314.1.0.1 to 14.1.1.25414.1.1.255510
13014.1.2.0/2314.1.2.1 to 14.1.3.25414.1.3.255510
13114.1.4.0/2314.1.4.1 to 14.1.5.25414.1.5.255510
13214.1.6.0/2314.1.6.1 to 14.1.7.25414.1.7.255510
13314.1.8.0/2314.1.8.1 to 14.1.9.25414.1.9.255510
13414.1.10.0/2314.1.10.1 to 14.1.11.25414.1.11.255510
13514.1.12.0/2314.1.12.1 to 14.1.13.25414.1.13.255510
13614.1.14.0/2314.1.14.1 to 14.1.15.25414.1.15.255510
13714.1.16.0/2314.1.16.1 to 14.1.17.25414.1.17.255510
13814.1.18.0/2314.1.18.1 to 14.1.19.25414.1.19.255510
13914.1.20.0/2314.1.20.1 to 14.1.21.25414.1.21.255510
14014.1.22.0/2314.1.22.1 to 14.1.23.25414.1.23.255510
14114.1.24.0/2314.1.24.1 to 14.1.25.25414.1.25.255510
14214.1.26.0/2314.1.26.1 to 14.1.27.25414.1.27.255510
14314.1.28.0/2314.1.28.1 to 14.1.29.25414.1.29.255510
14414.1.30.0/2314.1.30.1 to 14.1.31.25414.1.31.255510
14514.1.32.0/2314.1.32.1 to 14.1.33.25414.1.33.255510
14614.1.34.0/2314.1.34.1 to 14.1.35.25414.1.35.255510
14714.1.36.0/2314.1.36.1 to 14.1.37.25414.1.37.255510
14814.1.38.0/2314.1.38.1 to 14.1.39.25414.1.39.255510
14914.1.40.0/2314.1.40.1 to 14.1.41.25414.1.41.255510
15014.1.42.0/2314.1.42.1 to 14.1.43.25414.1.43.255510
15114.1.44.0/2314.1.44.1 to 14.1.45.25414.1.45.255510
15214.1.46.0/2314.1.46.1 to 14.1.47.25414.1.47.255510
15314.1.48.0/2314.1.48.1 to 14.1.49.25414.1.49.255510
15414.1.50.0/2314.1.50.1 to 14.1.51.25414.1.51.255510
15514.1.52.0/2314.1.52.1 to 14.1.53.25414.1.53.255510
15614.1.54.0/2314.1.54.1 to 14.1.55.25414.1.55.255510
15714.1.56.0/2314.1.56.1 to 14.1.57.25414.1.57.255510
15814.1.58.0/2314.1.58.1 to 14.1.59.25414.1.59.255510
15914.1.60.0/2314.1.60.1 to 14.1.61.25414.1.61.255510
16014.1.62.0/2314.1.62.1 to 14.1.63.25414.1.63.255510
16114.1.64.0/2314.1.64.1 to 14.1.65.25414.1.65.255510
16214.1.66.0/2314.1.66.1 to 14.1.67.25414.1.67.255510
16314.1.68.0/2314.1.68.1 to 14.1.69.25414.1.69.255510
16414.1.70.0/2314.1.70.1 to 14.1.71.25414.1.71.255510
16514.1.72.0/2314.1.72.1 to 14.1.73.25414.1.73.255510
16614.1.74.0/2314.1.74.1 to 14.1.75.25414.1.75.255510
16714.1.76.0/2314.1.76.1 to 14.1.77.25414.1.77.255510
16814.1.78.0/2314.1.78.1 to 14.1.79.25414.1.79.255510
16914.1.80.0/2314.1.80.1 to 14.1.81.25414.1.81.255510
17014.1.82.0/2314.1.82.1 to 14.1.83.25414.1.83.255510
17114.1.84.0/2314.1.84.1 to 14.1.85.25414.1.85.255510
17214.1.86.0/2314.1.86.1 to 14.1.87.25414.1.87.255510
17314.1.88.0/2314.1.88.1 to 14.1.89.25414.1.89.255510
17414.1.90.0/2314.1.90.1 to 14.1.91.25414.1.91.255510
17514.1.92.0/2314.1.92.1 to 14.1.93.25414.1.93.255510
17614.1.94.0/2314.1.94.1 to 14.1.95.25414.1.95.255510
17714.1.96.0/2314.1.96.1 to 14.1.97.25414.1.97.255510
17814.1.98.0/2314.1.98.1 to 14.1.99.25414.1.99.255510
17914.1.100.0/2314.1.100.1 to 14.1.101.25414.1.101.255510
18014.1.102.0/2314.1.102.1 to 14.1.103.25414.1.103.255510
18114.1.104.0/2314.1.104.1 to 14.1.105.25414.1.105.255510
18214.1.106.0/2314.1.106.1 to 14.1.107.25414.1.107.255510
18314.1.108.0/2314.1.108.1 to 14.1.109.25414.1.109.255510
18414.1.110.0/2314.1.110.1 to 14.1.111.25414.1.111.255510
18514.1.112.0/2314.1.112.1 to 14.1.113.25414.1.113.255510
18614.1.114.0/2314.1.114.1 to 14.1.115.25414.1.115.255510
18714.1.116.0/2314.1.116.1 to 14.1.117.25414.1.117.255510
18814.1.118.0/2314.1.118.1 to 14.1.119.25414.1.119.255510
18914.1.120.0/2314.1.120.1 to 14.1.121.25414.1.121.255510
19014.1.122.0/2314.1.122.1 to 14.1.123.25414.1.123.255510
19114.1.124.0/2314.1.124.1 to 14.1.125.25414.1.125.255510
19214.1.126.0/2314.1.126.1 to 14.1.127.25414.1.127.255510
19314.1.128.0/2314.1.128.1 to 14.1.129.25414.1.129.255510
19414.1.130.0/2314.1.130.1 to 14.1.131.25414.1.131.255510
19514.1.132.0/2314.1.132.1 to 14.1.133.25414.1.133.255510
19614.1.134.0/2314.1.134.1 to 14.1.135.25414.1.135.255510
19714.1.136.0/2314.1.136.1 to 14.1.137.25414.1.137.255510
19814.1.138.0/2314.1.138.1 to 14.1.139.25414.1.139.255510
19914.1.140.0/2314.1.140.1 to 14.1.141.25414.1.141.255510
20014.1.142.0/2314.1.142.1 to 14.1.143.25414.1.143.255510
20114.1.144.0/2314.1.144.1 to 14.1.145.25414.1.145.255510
20214.1.146.0/2314.1.146.1 to 14.1.147.25414.1.147.255510
20314.1.148.0/2314.1.148.1 to 14.1.149.25414.1.149.255510
20414.1.150.0/2314.1.150.1 to 14.1.151.25414.1.151.255510
20514.1.152.0/2314.1.152.1 to 14.1.153.25414.1.153.255510
20614.1.154.0/2314.1.154.1 to 14.1.155.25414.1.155.255510
20714.1.156.0/2314.1.156.1 to 14.1.157.25414.1.157.255510
20814.1.158.0/2314.1.158.1 to 14.1.159.25414.1.159.255510
20914.1.160.0/2314.1.160.1 to 14.1.161.25414.1.161.255510
21014.1.162.0/2314.1.162.1 to 14.1.163.25414.1.163.255510
21114.1.164.0/2314.1.164.1 to 14.1.165.25414.1.165.255510
21214.1.166.0/2314.1.166.1 to 14.1.167.25414.1.167.255510
21314.1.168.0/2314.1.168.1 to 14.1.169.25414.1.169.255510
21414.1.170.0/2314.1.170.1 to 14.1.171.25414.1.171.255510
21514.1.172.0/2314.1.172.1 to 14.1.173.25414.1.173.255510
21614.1.174.0/2314.1.174.1 to 14.1.175.25414.1.175.255510
21714.1.176.0/2314.1.176.1 to 14.1.177.25414.1.177.255510
21814.1.178.0/2314.1.178.1 to 14.1.179.25414.1.179.255510
21914.1.180.0/2314.1.180.1 to 14.1.181.25414.1.181.255510
22014.1.182.0/2314.1.182.1 to 14.1.183.25414.1.183.255510
22114.1.184.0/2314.1.184.1 to 14.1.185.25414.1.185.255510
22214.1.186.0/2314.1.186.1 to 14.1.187.25414.1.187.255510
22314.1.188.0/2314.1.188.1 to 14.1.189.25414.1.189.255510
22414.1.190.0/2314.1.190.1 to 14.1.191.25414.1.191.255510
22514.1.192.0/2314.1.192.1 to 14.1.193.25414.1.193.255510
22614.1.194.0/2314.1.194.1 to 14.1.195.25414.1.195.255510
22714.1.196.0/2314.1.196.1 to 14.1.197.25414.1.197.255510
22814.1.198.0/2314.1.198.1 to 14.1.199.25414.1.199.255510
22914.1.200.0/2314.1.200.1 to 14.1.201.25414.1.201.255510
23014.1.202.0/2314.1.202.1 to 14.1.203.25414.1.203.255510
23114.1.204.0/2314.1.204.1 to 14.1.205.25414.1.205.255510
23214.1.206.0/2314.1.206.1 to 14.1.207.25414.1.207.255510
23314.1.208.0/2314.1.208.1 to 14.1.209.25414.1.209.255510
23414.1.210.0/2314.1.210.1 to 14.1.211.25414.1.211.255510
23514.1.212.0/2314.1.212.1 to 14.1.213.25414.1.213.255510
23614.1.214.0/2314.1.214.1 to 14.1.215.25414.1.215.255510
23714.1.216.0/2314.1.216.1 to 14.1.217.25414.1.217.255510
23814.1.218.0/2314.1.218.1 to 14.1.219.25414.1.219.255510
23914.1.220.0/2314.1.220.1 to 14.1.221.25414.1.221.255510
24014.1.222.0/2314.1.222.1 to 14.1.223.25414.1.223.255510
24114.1.224.0/2314.1.224.1 to 14.1.225.25414.1.225.255510
24214.1.226.0/2314.1.226.1 to 14.1.227.25414.1.227.255510
24314.1.228.0/2314.1.228.1 to 14.1.229.25414.1.229.255510
24414.1.230.0/2314.1.230.1 to 14.1.231.25414.1.231.255510
24514.1.232.0/2314.1.232.1 to 14.1.233.25414.1.233.255510
24614.1.234.0/2314.1.234.1 to 14.1.235.25414.1.235.255510
24714.1.236.0/2314.1.236.1 to 14.1.237.25414.1.237.255510
24814.1.238.0/2314.1.238.1 to 14.1.239.25414.1.239.255510
24914.1.240.0/2314.1.240.1 to 14.1.241.25414.1.241.255510
25014.1.242.0/2314.1.242.1 to 14.1.243.25414.1.243.255510
25114.1.244.0/2314.1.244.1 to 14.1.245.25414.1.245.255510
25214.1.246.0/2314.1.246.1 to 14.1.247.25414.1.247.255510
25314.1.248.0/2314.1.248.1 to 14.1.249.25414.1.249.255510
25414.1.250.0/2314.1.250.1 to 14.1.251.25414.1.251.255510
25514.1.252.0/2314.1.252.1 to 14.1.253.25414.1.253.255510
25614.1.254.0/2314.1.254.1 to 14.1.255.25414.1.255.255510

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.