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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/15
/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 256 subnets of /15.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
114.0.0.0/1514.0.0.1 to 14.1.255.25414.1.255.255131,070
214.2.0.0/1514.2.0.1 to 14.3.255.25414.3.255.255131,070
314.4.0.0/1514.4.0.1 to 14.5.255.25414.5.255.255131,070
414.6.0.0/1514.6.0.1 to 14.7.255.25414.7.255.255131,070
514.8.0.0/1514.8.0.1 to 14.9.255.25414.9.255.255131,070
614.10.0.0/1514.10.0.1 to 14.11.255.25414.11.255.255131,070
714.12.0.0/1514.12.0.1 to 14.13.255.25414.13.255.255131,070
814.14.0.0/1514.14.0.1 to 14.15.255.25414.15.255.255131,070
914.16.0.0/1514.16.0.1 to 14.17.255.25414.17.255.255131,070
1014.18.0.0/1514.18.0.1 to 14.19.255.25414.19.255.255131,070
1114.20.0.0/1514.20.0.1 to 14.21.255.25414.21.255.255131,070
1214.22.0.0/1514.22.0.1 to 14.23.255.25414.23.255.255131,070
1314.24.0.0/1514.24.0.1 to 14.25.255.25414.25.255.255131,070
1414.26.0.0/1514.26.0.1 to 14.27.255.25414.27.255.255131,070
1514.28.0.0/1514.28.0.1 to 14.29.255.25414.29.255.255131,070
1614.30.0.0/1514.30.0.1 to 14.31.255.25414.31.255.255131,070
1714.32.0.0/1514.32.0.1 to 14.33.255.25414.33.255.255131,070
1814.34.0.0/1514.34.0.1 to 14.35.255.25414.35.255.255131,070
1914.36.0.0/1514.36.0.1 to 14.37.255.25414.37.255.255131,070
2014.38.0.0/1514.38.0.1 to 14.39.255.25414.39.255.255131,070
2114.40.0.0/1514.40.0.1 to 14.41.255.25414.41.255.255131,070
2214.42.0.0/1514.42.0.1 to 14.43.255.25414.43.255.255131,070
2314.44.0.0/1514.44.0.1 to 14.45.255.25414.45.255.255131,070
2414.46.0.0/1514.46.0.1 to 14.47.255.25414.47.255.255131,070
2514.48.0.0/1514.48.0.1 to 14.49.255.25414.49.255.255131,070
2614.50.0.0/1514.50.0.1 to 14.51.255.25414.51.255.255131,070
2714.52.0.0/1514.52.0.1 to 14.53.255.25414.53.255.255131,070
2814.54.0.0/1514.54.0.1 to 14.55.255.25414.55.255.255131,070
2914.56.0.0/1514.56.0.1 to 14.57.255.25414.57.255.255131,070
3014.58.0.0/1514.58.0.1 to 14.59.255.25414.59.255.255131,070
3114.60.0.0/1514.60.0.1 to 14.61.255.25414.61.255.255131,070
3214.62.0.0/1514.62.0.1 to 14.63.255.25414.63.255.255131,070
3314.64.0.0/1514.64.0.1 to 14.65.255.25414.65.255.255131,070
3414.66.0.0/1514.66.0.1 to 14.67.255.25414.67.255.255131,070
3514.68.0.0/1514.68.0.1 to 14.69.255.25414.69.255.255131,070
3614.70.0.0/1514.70.0.1 to 14.71.255.25414.71.255.255131,070
3714.72.0.0/1514.72.0.1 to 14.73.255.25414.73.255.255131,070
3814.74.0.0/1514.74.0.1 to 14.75.255.25414.75.255.255131,070
3914.76.0.0/1514.76.0.1 to 14.77.255.25414.77.255.255131,070
4014.78.0.0/1514.78.0.1 to 14.79.255.25414.79.255.255131,070
4114.80.0.0/1514.80.0.1 to 14.81.255.25414.81.255.255131,070
4214.82.0.0/1514.82.0.1 to 14.83.255.25414.83.255.255131,070
4314.84.0.0/1514.84.0.1 to 14.85.255.25414.85.255.255131,070
4414.86.0.0/1514.86.0.1 to 14.87.255.25414.87.255.255131,070
4514.88.0.0/1514.88.0.1 to 14.89.255.25414.89.255.255131,070
4614.90.0.0/1514.90.0.1 to 14.91.255.25414.91.255.255131,070
4714.92.0.0/1514.92.0.1 to 14.93.255.25414.93.255.255131,070
4814.94.0.0/1514.94.0.1 to 14.95.255.25414.95.255.255131,070
4914.96.0.0/1514.96.0.1 to 14.97.255.25414.97.255.255131,070
5014.98.0.0/1514.98.0.1 to 14.99.255.25414.99.255.255131,070
5114.100.0.0/1514.100.0.1 to 14.101.255.25414.101.255.255131,070
5214.102.0.0/1514.102.0.1 to 14.103.255.25414.103.255.255131,070
5314.104.0.0/1514.104.0.1 to 14.105.255.25414.105.255.255131,070
5414.106.0.0/1514.106.0.1 to 14.107.255.25414.107.255.255131,070
5514.108.0.0/1514.108.0.1 to 14.109.255.25414.109.255.255131,070
5614.110.0.0/1514.110.0.1 to 14.111.255.25414.111.255.255131,070
5714.112.0.0/1514.112.0.1 to 14.113.255.25414.113.255.255131,070
5814.114.0.0/1514.114.0.1 to 14.115.255.25414.115.255.255131,070
5914.116.0.0/1514.116.0.1 to 14.117.255.25414.117.255.255131,070
6014.118.0.0/1514.118.0.1 to 14.119.255.25414.119.255.255131,070
6114.120.0.0/1514.120.0.1 to 14.121.255.25414.121.255.255131,070
6214.122.0.0/1514.122.0.1 to 14.123.255.25414.123.255.255131,070
6314.124.0.0/1514.124.0.1 to 14.125.255.25414.125.255.255131,070
6414.126.0.0/1514.126.0.1 to 14.127.255.25414.127.255.255131,070
6514.128.0.0/1514.128.0.1 to 14.129.255.25414.129.255.255131,070
6614.130.0.0/1514.130.0.1 to 14.131.255.25414.131.255.255131,070
6714.132.0.0/1514.132.0.1 to 14.133.255.25414.133.255.255131,070
6814.134.0.0/1514.134.0.1 to 14.135.255.25414.135.255.255131,070
6914.136.0.0/1514.136.0.1 to 14.137.255.25414.137.255.255131,070
7014.138.0.0/1514.138.0.1 to 14.139.255.25414.139.255.255131,070
7114.140.0.0/1514.140.0.1 to 14.141.255.25414.141.255.255131,070
7214.142.0.0/1514.142.0.1 to 14.143.255.25414.143.255.255131,070
7314.144.0.0/1514.144.0.1 to 14.145.255.25414.145.255.255131,070
7414.146.0.0/1514.146.0.1 to 14.147.255.25414.147.255.255131,070
7514.148.0.0/1514.148.0.1 to 14.149.255.25414.149.255.255131,070
7614.150.0.0/1514.150.0.1 to 14.151.255.25414.151.255.255131,070
7714.152.0.0/1514.152.0.1 to 14.153.255.25414.153.255.255131,070
7814.154.0.0/1514.154.0.1 to 14.155.255.25414.155.255.255131,070
7914.156.0.0/1514.156.0.1 to 14.157.255.25414.157.255.255131,070
8014.158.0.0/1514.158.0.1 to 14.159.255.25414.159.255.255131,070
8114.160.0.0/1514.160.0.1 to 14.161.255.25414.161.255.255131,070
8214.162.0.0/1514.162.0.1 to 14.163.255.25414.163.255.255131,070
8314.164.0.0/1514.164.0.1 to 14.165.255.25414.165.255.255131,070
8414.166.0.0/1514.166.0.1 to 14.167.255.25414.167.255.255131,070
8514.168.0.0/1514.168.0.1 to 14.169.255.25414.169.255.255131,070
8614.170.0.0/1514.170.0.1 to 14.171.255.25414.171.255.255131,070
8714.172.0.0/1514.172.0.1 to 14.173.255.25414.173.255.255131,070
8814.174.0.0/1514.174.0.1 to 14.175.255.25414.175.255.255131,070
8914.176.0.0/1514.176.0.1 to 14.177.255.25414.177.255.255131,070
9014.178.0.0/1514.178.0.1 to 14.179.255.25414.179.255.255131,070
9114.180.0.0/1514.180.0.1 to 14.181.255.25414.181.255.255131,070
9214.182.0.0/1514.182.0.1 to 14.183.255.25414.183.255.255131,070
9314.184.0.0/1514.184.0.1 to 14.185.255.25414.185.255.255131,070
9414.186.0.0/1514.186.0.1 to 14.187.255.25414.187.255.255131,070
9514.188.0.0/1514.188.0.1 to 14.189.255.25414.189.255.255131,070
9614.190.0.0/1514.190.0.1 to 14.191.255.25414.191.255.255131,070
9714.192.0.0/1514.192.0.1 to 14.193.255.25414.193.255.255131,070
9814.194.0.0/1514.194.0.1 to 14.195.255.25414.195.255.255131,070
9914.196.0.0/1514.196.0.1 to 14.197.255.25414.197.255.255131,070
10014.198.0.0/1514.198.0.1 to 14.199.255.25414.199.255.255131,070
10114.200.0.0/1514.200.0.1 to 14.201.255.25414.201.255.255131,070
10214.202.0.0/1514.202.0.1 to 14.203.255.25414.203.255.255131,070
10314.204.0.0/1514.204.0.1 to 14.205.255.25414.205.255.255131,070
10414.206.0.0/1514.206.0.1 to 14.207.255.25414.207.255.255131,070
10514.208.0.0/1514.208.0.1 to 14.209.255.25414.209.255.255131,070
10614.210.0.0/1514.210.0.1 to 14.211.255.25414.211.255.255131,070
10714.212.0.0/1514.212.0.1 to 14.213.255.25414.213.255.255131,070
10814.214.0.0/1514.214.0.1 to 14.215.255.25414.215.255.255131,070
10914.216.0.0/1514.216.0.1 to 14.217.255.25414.217.255.255131,070
11014.218.0.0/1514.218.0.1 to 14.219.255.25414.219.255.255131,070
11114.220.0.0/1514.220.0.1 to 14.221.255.25414.221.255.255131,070
11214.222.0.0/1514.222.0.1 to 14.223.255.25414.223.255.255131,070
11314.224.0.0/1514.224.0.1 to 14.225.255.25414.225.255.255131,070
11414.226.0.0/1514.226.0.1 to 14.227.255.25414.227.255.255131,070
11514.228.0.0/1514.228.0.1 to 14.229.255.25414.229.255.255131,070
11614.230.0.0/1514.230.0.1 to 14.231.255.25414.231.255.255131,070
11714.232.0.0/1514.232.0.1 to 14.233.255.25414.233.255.255131,070
11814.234.0.0/1514.234.0.1 to 14.235.255.25414.235.255.255131,070
11914.236.0.0/1514.236.0.1 to 14.237.255.25414.237.255.255131,070
12014.238.0.0/1514.238.0.1 to 14.239.255.25414.239.255.255131,070
12114.240.0.0/1514.240.0.1 to 14.241.255.25414.241.255.255131,070
12214.242.0.0/1514.242.0.1 to 14.243.255.25414.243.255.255131,070
12314.244.0.0/1514.244.0.1 to 14.245.255.25414.245.255.255131,070
12414.246.0.0/1514.246.0.1 to 14.247.255.25414.247.255.255131,070
12514.248.0.0/1514.248.0.1 to 14.249.255.25414.249.255.255131,070
12614.250.0.0/1514.250.0.1 to 14.251.255.25414.251.255.255131,070
12714.252.0.0/1514.252.0.1 to 14.253.255.25414.253.255.255131,070
12814.254.0.0/1514.254.0.1 to 14.255.255.25414.255.255.255131,070
12915.0.0.0/1515.0.0.1 to 15.1.255.25415.1.255.255131,070
13015.2.0.0/1515.2.0.1 to 15.3.255.25415.3.255.255131,070
13115.4.0.0/1515.4.0.1 to 15.5.255.25415.5.255.255131,070
13215.6.0.0/1515.6.0.1 to 15.7.255.25415.7.255.255131,070
13315.8.0.0/1515.8.0.1 to 15.9.255.25415.9.255.255131,070
13415.10.0.0/1515.10.0.1 to 15.11.255.25415.11.255.255131,070
13515.12.0.0/1515.12.0.1 to 15.13.255.25415.13.255.255131,070
13615.14.0.0/1515.14.0.1 to 15.15.255.25415.15.255.255131,070
13715.16.0.0/1515.16.0.1 to 15.17.255.25415.17.255.255131,070
13815.18.0.0/1515.18.0.1 to 15.19.255.25415.19.255.255131,070
13915.20.0.0/1515.20.0.1 to 15.21.255.25415.21.255.255131,070
14015.22.0.0/1515.22.0.1 to 15.23.255.25415.23.255.255131,070
14115.24.0.0/1515.24.0.1 to 15.25.255.25415.25.255.255131,070
14215.26.0.0/1515.26.0.1 to 15.27.255.25415.27.255.255131,070
14315.28.0.0/1515.28.0.1 to 15.29.255.25415.29.255.255131,070
14415.30.0.0/1515.30.0.1 to 15.31.255.25415.31.255.255131,070
14515.32.0.0/1515.32.0.1 to 15.33.255.25415.33.255.255131,070
14615.34.0.0/1515.34.0.1 to 15.35.255.25415.35.255.255131,070
14715.36.0.0/1515.36.0.1 to 15.37.255.25415.37.255.255131,070
14815.38.0.0/1515.38.0.1 to 15.39.255.25415.39.255.255131,070
14915.40.0.0/1515.40.0.1 to 15.41.255.25415.41.255.255131,070
15015.42.0.0/1515.42.0.1 to 15.43.255.25415.43.255.255131,070
15115.44.0.0/1515.44.0.1 to 15.45.255.25415.45.255.255131,070
15215.46.0.0/1515.46.0.1 to 15.47.255.25415.47.255.255131,070
15315.48.0.0/1515.48.0.1 to 15.49.255.25415.49.255.255131,070
15415.50.0.0/1515.50.0.1 to 15.51.255.25415.51.255.255131,070
15515.52.0.0/1515.52.0.1 to 15.53.255.25415.53.255.255131,070
15615.54.0.0/1515.54.0.1 to 15.55.255.25415.55.255.255131,070
15715.56.0.0/1515.56.0.1 to 15.57.255.25415.57.255.255131,070
15815.58.0.0/1515.58.0.1 to 15.59.255.25415.59.255.255131,070
15915.60.0.0/1515.60.0.1 to 15.61.255.25415.61.255.255131,070
16015.62.0.0/1515.62.0.1 to 15.63.255.25415.63.255.255131,070
16115.64.0.0/1515.64.0.1 to 15.65.255.25415.65.255.255131,070
16215.66.0.0/1515.66.0.1 to 15.67.255.25415.67.255.255131,070
16315.68.0.0/1515.68.0.1 to 15.69.255.25415.69.255.255131,070
16415.70.0.0/1515.70.0.1 to 15.71.255.25415.71.255.255131,070
16515.72.0.0/1515.72.0.1 to 15.73.255.25415.73.255.255131,070
16615.74.0.0/1515.74.0.1 to 15.75.255.25415.75.255.255131,070
16715.76.0.0/1515.76.0.1 to 15.77.255.25415.77.255.255131,070
16815.78.0.0/1515.78.0.1 to 15.79.255.25415.79.255.255131,070
16915.80.0.0/1515.80.0.1 to 15.81.255.25415.81.255.255131,070
17015.82.0.0/1515.82.0.1 to 15.83.255.25415.83.255.255131,070
17115.84.0.0/1515.84.0.1 to 15.85.255.25415.85.255.255131,070
17215.86.0.0/1515.86.0.1 to 15.87.255.25415.87.255.255131,070
17315.88.0.0/1515.88.0.1 to 15.89.255.25415.89.255.255131,070
17415.90.0.0/1515.90.0.1 to 15.91.255.25415.91.255.255131,070
17515.92.0.0/1515.92.0.1 to 15.93.255.25415.93.255.255131,070
17615.94.0.0/1515.94.0.1 to 15.95.255.25415.95.255.255131,070
17715.96.0.0/1515.96.0.1 to 15.97.255.25415.97.255.255131,070
17815.98.0.0/1515.98.0.1 to 15.99.255.25415.99.255.255131,070
17915.100.0.0/1515.100.0.1 to 15.101.255.25415.101.255.255131,070
18015.102.0.0/1515.102.0.1 to 15.103.255.25415.103.255.255131,070
18115.104.0.0/1515.104.0.1 to 15.105.255.25415.105.255.255131,070
18215.106.0.0/1515.106.0.1 to 15.107.255.25415.107.255.255131,070
18315.108.0.0/1515.108.0.1 to 15.109.255.25415.109.255.255131,070
18415.110.0.0/1515.110.0.1 to 15.111.255.25415.111.255.255131,070
18515.112.0.0/1515.112.0.1 to 15.113.255.25415.113.255.255131,070
18615.114.0.0/1515.114.0.1 to 15.115.255.25415.115.255.255131,070
18715.116.0.0/1515.116.0.1 to 15.117.255.25415.117.255.255131,070
18815.118.0.0/1515.118.0.1 to 15.119.255.25415.119.255.255131,070
18915.120.0.0/1515.120.0.1 to 15.121.255.25415.121.255.255131,070
19015.122.0.0/1515.122.0.1 to 15.123.255.25415.123.255.255131,070
19115.124.0.0/1515.124.0.1 to 15.125.255.25415.125.255.255131,070
19215.126.0.0/1515.126.0.1 to 15.127.255.25415.127.255.255131,070
19315.128.0.0/1515.128.0.1 to 15.129.255.25415.129.255.255131,070
19415.130.0.0/1515.130.0.1 to 15.131.255.25415.131.255.255131,070
19515.132.0.0/1515.132.0.1 to 15.133.255.25415.133.255.255131,070
19615.134.0.0/1515.134.0.1 to 15.135.255.25415.135.255.255131,070
19715.136.0.0/1515.136.0.1 to 15.137.255.25415.137.255.255131,070
19815.138.0.0/1515.138.0.1 to 15.139.255.25415.139.255.255131,070
19915.140.0.0/1515.140.0.1 to 15.141.255.25415.141.255.255131,070
20015.142.0.0/1515.142.0.1 to 15.143.255.25415.143.255.255131,070
20115.144.0.0/1515.144.0.1 to 15.145.255.25415.145.255.255131,070
20215.146.0.0/1515.146.0.1 to 15.147.255.25415.147.255.255131,070
20315.148.0.0/1515.148.0.1 to 15.149.255.25415.149.255.255131,070
20415.150.0.0/1515.150.0.1 to 15.151.255.25415.151.255.255131,070
20515.152.0.0/1515.152.0.1 to 15.153.255.25415.153.255.255131,070
20615.154.0.0/1515.154.0.1 to 15.155.255.25415.155.255.255131,070
20715.156.0.0/1515.156.0.1 to 15.157.255.25415.157.255.255131,070
20815.158.0.0/1515.158.0.1 to 15.159.255.25415.159.255.255131,070
20915.160.0.0/1515.160.0.1 to 15.161.255.25415.161.255.255131,070
21015.162.0.0/1515.162.0.1 to 15.163.255.25415.163.255.255131,070
21115.164.0.0/1515.164.0.1 to 15.165.255.25415.165.255.255131,070
21215.166.0.0/1515.166.0.1 to 15.167.255.25415.167.255.255131,070
21315.168.0.0/1515.168.0.1 to 15.169.255.25415.169.255.255131,070
21415.170.0.0/1515.170.0.1 to 15.171.255.25415.171.255.255131,070
21515.172.0.0/1515.172.0.1 to 15.173.255.25415.173.255.255131,070
21615.174.0.0/1515.174.0.1 to 15.175.255.25415.175.255.255131,070
21715.176.0.0/1515.176.0.1 to 15.177.255.25415.177.255.255131,070
21815.178.0.0/1515.178.0.1 to 15.179.255.25415.179.255.255131,070
21915.180.0.0/1515.180.0.1 to 15.181.255.25415.181.255.255131,070
22015.182.0.0/1515.182.0.1 to 15.183.255.25415.183.255.255131,070
22115.184.0.0/1515.184.0.1 to 15.185.255.25415.185.255.255131,070
22215.186.0.0/1515.186.0.1 to 15.187.255.25415.187.255.255131,070
22315.188.0.0/1515.188.0.1 to 15.189.255.25415.189.255.255131,070
22415.190.0.0/1515.190.0.1 to 15.191.255.25415.191.255.255131,070
22515.192.0.0/1515.192.0.1 to 15.193.255.25415.193.255.255131,070
22615.194.0.0/1515.194.0.1 to 15.195.255.25415.195.255.255131,070
22715.196.0.0/1515.196.0.1 to 15.197.255.25415.197.255.255131,070
22815.198.0.0/1515.198.0.1 to 15.199.255.25415.199.255.255131,070
22915.200.0.0/1515.200.0.1 to 15.201.255.25415.201.255.255131,070
23015.202.0.0/1515.202.0.1 to 15.203.255.25415.203.255.255131,070
23115.204.0.0/1515.204.0.1 to 15.205.255.25415.205.255.255131,070
23215.206.0.0/1515.206.0.1 to 15.207.255.25415.207.255.255131,070
23315.208.0.0/1515.208.0.1 to 15.209.255.25415.209.255.255131,070
23415.210.0.0/1515.210.0.1 to 15.211.255.25415.211.255.255131,070
23515.212.0.0/1515.212.0.1 to 15.213.255.25415.213.255.255131,070
23615.214.0.0/1515.214.0.1 to 15.215.255.25415.215.255.255131,070
23715.216.0.0/1515.216.0.1 to 15.217.255.25415.217.255.255131,070
23815.218.0.0/1515.218.0.1 to 15.219.255.25415.219.255.255131,070
23915.220.0.0/1515.220.0.1 to 15.221.255.25415.221.255.255131,070
24015.222.0.0/1515.222.0.1 to 15.223.255.25415.223.255.255131,070
24115.224.0.0/1515.224.0.1 to 15.225.255.25415.225.255.255131,070
24215.226.0.0/1515.226.0.1 to 15.227.255.25415.227.255.255131,070
24315.228.0.0/1515.228.0.1 to 15.229.255.25415.229.255.255131,070
24415.230.0.0/1515.230.0.1 to 15.231.255.25415.231.255.255131,070
24515.232.0.0/1515.232.0.1 to 15.233.255.25415.233.255.255131,070
24615.234.0.0/1515.234.0.1 to 15.235.255.25415.235.255.255131,070
24715.236.0.0/1515.236.0.1 to 15.237.255.25415.237.255.255131,070
24815.238.0.0/1515.238.0.1 to 15.239.255.25415.239.255.255131,070
24915.240.0.0/1515.240.0.1 to 15.241.255.25415.241.255.255131,070
25015.242.0.0/1515.242.0.1 to 15.243.255.25415.243.255.255131,070
25115.244.0.0/1515.244.0.1 to 15.245.255.25415.245.255.255131,070
25215.246.0.0/1515.246.0.1 to 15.247.255.25415.247.255.255131,070
25315.248.0.0/1515.248.0.1 to 15.249.255.25415.249.255.255131,070
25415.250.0.0/1515.250.0.1 to 15.251.255.25415.251.255.255131,070
25515.252.0.0/1515.252.0.1 to 15.253.255.25415.253.255.255131,070
25615.254.0.0/1515.254.0.1 to 15.255.255.25415.255.255.255131,070

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.