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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.

Network14.96.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
14.96.0.0
Broadcast address
14.127.255.255
First usable
14.96.0.1
Last usable
14.127.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Public public
Old class
A (default /8)
As numbers
Hex 0E600000 · Integer 241172480 to 243269631
Reverse DNS zones
96.14.in-addr.arpa
97.14.in-addr.arpa
98.14.in-addr.arpa
99.14.in-addr.arpa
100.14.in-addr.arpa
101.14.in-addr.arpa
102.14.in-addr.arpa
103.14.in-addr.arpa
104.14.in-addr.arpa
105.14.in-addr.arpa
106.14.in-addr.arpa
107.14.in-addr.arpa
108.14.in-addr.arpa
109.14.in-addr.arpa
110.14.in-addr.arpa
111.14.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00001110.01100000.00000000.0000000014.96.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network00001110.01100000.00000000.0000000014.96.0.0
Broadcast00001110.01111111.11111111.1111111114.127.255.255
Split into smaller subnets/21
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

14.96.0.0/11 makes 1,024 subnets of /21; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
114.96.0.0/2114.96.0.1 to 14.96.7.25414.96.7.2552,046
214.96.8.0/2114.96.8.1 to 14.96.15.25414.96.15.2552,046
314.96.16.0/2114.96.16.1 to 14.96.23.25414.96.23.2552,046
414.96.24.0/2114.96.24.1 to 14.96.31.25414.96.31.2552,046
514.96.32.0/2114.96.32.1 to 14.96.39.25414.96.39.2552,046
614.96.40.0/2114.96.40.1 to 14.96.47.25414.96.47.2552,046
714.96.48.0/2114.96.48.1 to 14.96.55.25414.96.55.2552,046
814.96.56.0/2114.96.56.1 to 14.96.63.25414.96.63.2552,046
914.96.64.0/2114.96.64.1 to 14.96.71.25414.96.71.2552,046
1014.96.72.0/2114.96.72.1 to 14.96.79.25414.96.79.2552,046
1114.96.80.0/2114.96.80.1 to 14.96.87.25414.96.87.2552,046
1214.96.88.0/2114.96.88.1 to 14.96.95.25414.96.95.2552,046
1314.96.96.0/2114.96.96.1 to 14.96.103.25414.96.103.2552,046
1414.96.104.0/2114.96.104.1 to 14.96.111.25414.96.111.2552,046
1514.96.112.0/2114.96.112.1 to 14.96.119.25414.96.119.2552,046
1614.96.120.0/2114.96.120.1 to 14.96.127.25414.96.127.2552,046
1714.96.128.0/2114.96.128.1 to 14.96.135.25414.96.135.2552,046
1814.96.136.0/2114.96.136.1 to 14.96.143.25414.96.143.2552,046
1914.96.144.0/2114.96.144.1 to 14.96.151.25414.96.151.2552,046
2014.96.152.0/2114.96.152.1 to 14.96.159.25414.96.159.2552,046
2114.96.160.0/2114.96.160.1 to 14.96.167.25414.96.167.2552,046
2214.96.168.0/2114.96.168.1 to 14.96.175.25414.96.175.2552,046
2314.96.176.0/2114.96.176.1 to 14.96.183.25414.96.183.2552,046
2414.96.184.0/2114.96.184.1 to 14.96.191.25414.96.191.2552,046
2514.96.192.0/2114.96.192.1 to 14.96.199.25414.96.199.2552,046
2614.96.200.0/2114.96.200.1 to 14.96.207.25414.96.207.2552,046
2714.96.208.0/2114.96.208.1 to 14.96.215.25414.96.215.2552,046
2814.96.216.0/2114.96.216.1 to 14.96.223.25414.96.223.2552,046
2914.96.224.0/2114.96.224.1 to 14.96.231.25414.96.231.2552,046
3014.96.232.0/2114.96.232.1 to 14.96.239.25414.96.239.2552,046
3114.96.240.0/2114.96.240.1 to 14.96.247.25414.96.247.2552,046
3214.96.248.0/2114.96.248.1 to 14.96.255.25414.96.255.2552,046
3314.97.0.0/2114.97.0.1 to 14.97.7.25414.97.7.2552,046
3414.97.8.0/2114.97.8.1 to 14.97.15.25414.97.15.2552,046
3514.97.16.0/2114.97.16.1 to 14.97.23.25414.97.23.2552,046
3614.97.24.0/2114.97.24.1 to 14.97.31.25414.97.31.2552,046
3714.97.32.0/2114.97.32.1 to 14.97.39.25414.97.39.2552,046
3814.97.40.0/2114.97.40.1 to 14.97.47.25414.97.47.2552,046
3914.97.48.0/2114.97.48.1 to 14.97.55.25414.97.55.2552,046
4014.97.56.0/2114.97.56.1 to 14.97.63.25414.97.63.2552,046
4114.97.64.0/2114.97.64.1 to 14.97.71.25414.97.71.2552,046
4214.97.72.0/2114.97.72.1 to 14.97.79.25414.97.79.2552,046
4314.97.80.0/2114.97.80.1 to 14.97.87.25414.97.87.2552,046
4414.97.88.0/2114.97.88.1 to 14.97.95.25414.97.95.2552,046
4514.97.96.0/2114.97.96.1 to 14.97.103.25414.97.103.2552,046
4614.97.104.0/2114.97.104.1 to 14.97.111.25414.97.111.2552,046
4714.97.112.0/2114.97.112.1 to 14.97.119.25414.97.119.2552,046
4814.97.120.0/2114.97.120.1 to 14.97.127.25414.97.127.2552,046
4914.97.128.0/2114.97.128.1 to 14.97.135.25414.97.135.2552,046
5014.97.136.0/2114.97.136.1 to 14.97.143.25414.97.143.2552,046
5114.97.144.0/2114.97.144.1 to 14.97.151.25414.97.151.2552,046
5214.97.152.0/2114.97.152.1 to 14.97.159.25414.97.159.2552,046
5314.97.160.0/2114.97.160.1 to 14.97.167.25414.97.167.2552,046
5414.97.168.0/2114.97.168.1 to 14.97.175.25414.97.175.2552,046
5514.97.176.0/2114.97.176.1 to 14.97.183.25414.97.183.2552,046
5614.97.184.0/2114.97.184.1 to 14.97.191.25414.97.191.2552,046
5714.97.192.0/2114.97.192.1 to 14.97.199.25414.97.199.2552,046
5814.97.200.0/2114.97.200.1 to 14.97.207.25414.97.207.2552,046
5914.97.208.0/2114.97.208.1 to 14.97.215.25414.97.215.2552,046
6014.97.216.0/2114.97.216.1 to 14.97.223.25414.97.223.2552,046
6114.97.224.0/2114.97.224.1 to 14.97.231.25414.97.231.2552,046
6214.97.232.0/2114.97.232.1 to 14.97.239.25414.97.239.2552,046
6314.97.240.0/2114.97.240.1 to 14.97.247.25414.97.247.2552,046
6414.97.248.0/2114.97.248.1 to 14.97.255.25414.97.255.2552,046
6514.98.0.0/2114.98.0.1 to 14.98.7.25414.98.7.2552,046
6614.98.8.0/2114.98.8.1 to 14.98.15.25414.98.15.2552,046
6714.98.16.0/2114.98.16.1 to 14.98.23.25414.98.23.2552,046
6814.98.24.0/2114.98.24.1 to 14.98.31.25414.98.31.2552,046
6914.98.32.0/2114.98.32.1 to 14.98.39.25414.98.39.2552,046
7014.98.40.0/2114.98.40.1 to 14.98.47.25414.98.47.2552,046
7114.98.48.0/2114.98.48.1 to 14.98.55.25414.98.55.2552,046
7214.98.56.0/2114.98.56.1 to 14.98.63.25414.98.63.2552,046
7314.98.64.0/2114.98.64.1 to 14.98.71.25414.98.71.2552,046
7414.98.72.0/2114.98.72.1 to 14.98.79.25414.98.79.2552,046
7514.98.80.0/2114.98.80.1 to 14.98.87.25414.98.87.2552,046
7614.98.88.0/2114.98.88.1 to 14.98.95.25414.98.95.2552,046
7714.98.96.0/2114.98.96.1 to 14.98.103.25414.98.103.2552,046
7814.98.104.0/2114.98.104.1 to 14.98.111.25414.98.111.2552,046
7914.98.112.0/2114.98.112.1 to 14.98.119.25414.98.119.2552,046
8014.98.120.0/2114.98.120.1 to 14.98.127.25414.98.127.2552,046
8114.98.128.0/2114.98.128.1 to 14.98.135.25414.98.135.2552,046
8214.98.136.0/2114.98.136.1 to 14.98.143.25414.98.143.2552,046
8314.98.144.0/2114.98.144.1 to 14.98.151.25414.98.151.2552,046
8414.98.152.0/2114.98.152.1 to 14.98.159.25414.98.159.2552,046
8514.98.160.0/2114.98.160.1 to 14.98.167.25414.98.167.2552,046
8614.98.168.0/2114.98.168.1 to 14.98.175.25414.98.175.2552,046
8714.98.176.0/2114.98.176.1 to 14.98.183.25414.98.183.2552,046
8814.98.184.0/2114.98.184.1 to 14.98.191.25414.98.191.2552,046
8914.98.192.0/2114.98.192.1 to 14.98.199.25414.98.199.2552,046
9014.98.200.0/2114.98.200.1 to 14.98.207.25414.98.207.2552,046
9114.98.208.0/2114.98.208.1 to 14.98.215.25414.98.215.2552,046
9214.98.216.0/2114.98.216.1 to 14.98.223.25414.98.223.2552,046
9314.98.224.0/2114.98.224.1 to 14.98.231.25414.98.231.2552,046
9414.98.232.0/2114.98.232.1 to 14.98.239.25414.98.239.2552,046
9514.98.240.0/2114.98.240.1 to 14.98.247.25414.98.247.2552,046
9614.98.248.0/2114.98.248.1 to 14.98.255.25414.98.255.2552,046
9714.99.0.0/2114.99.0.1 to 14.99.7.25414.99.7.2552,046
9814.99.8.0/2114.99.8.1 to 14.99.15.25414.99.15.2552,046
9914.99.16.0/2114.99.16.1 to 14.99.23.25414.99.23.2552,046
10014.99.24.0/2114.99.24.1 to 14.99.31.25414.99.31.2552,046
10114.99.32.0/2114.99.32.1 to 14.99.39.25414.99.39.2552,046
10214.99.40.0/2114.99.40.1 to 14.99.47.25414.99.47.2552,046
10314.99.48.0/2114.99.48.1 to 14.99.55.25414.99.55.2552,046
10414.99.56.0/2114.99.56.1 to 14.99.63.25414.99.63.2552,046
10514.99.64.0/2114.99.64.1 to 14.99.71.25414.99.71.2552,046
10614.99.72.0/2114.99.72.1 to 14.99.79.25414.99.79.2552,046
10714.99.80.0/2114.99.80.1 to 14.99.87.25414.99.87.2552,046
10814.99.88.0/2114.99.88.1 to 14.99.95.25414.99.95.2552,046
10914.99.96.0/2114.99.96.1 to 14.99.103.25414.99.103.2552,046
11014.99.104.0/2114.99.104.1 to 14.99.111.25414.99.111.2552,046
11114.99.112.0/2114.99.112.1 to 14.99.119.25414.99.119.2552,046
11214.99.120.0/2114.99.120.1 to 14.99.127.25414.99.127.2552,046
11314.99.128.0/2114.99.128.1 to 14.99.135.25414.99.135.2552,046
11414.99.136.0/2114.99.136.1 to 14.99.143.25414.99.143.2552,046
11514.99.144.0/2114.99.144.1 to 14.99.151.25414.99.151.2552,046
11614.99.152.0/2114.99.152.1 to 14.99.159.25414.99.159.2552,046
11714.99.160.0/2114.99.160.1 to 14.99.167.25414.99.167.2552,046
11814.99.168.0/2114.99.168.1 to 14.99.175.25414.99.175.2552,046
11914.99.176.0/2114.99.176.1 to 14.99.183.25414.99.183.2552,046
12014.99.184.0/2114.99.184.1 to 14.99.191.25414.99.191.2552,046
12114.99.192.0/2114.99.192.1 to 14.99.199.25414.99.199.2552,046
12214.99.200.0/2114.99.200.1 to 14.99.207.25414.99.207.2552,046
12314.99.208.0/2114.99.208.1 to 14.99.215.25414.99.215.2552,046
12414.99.216.0/2114.99.216.1 to 14.99.223.25414.99.223.2552,046
12514.99.224.0/2114.99.224.1 to 14.99.231.25414.99.231.2552,046
12614.99.232.0/2114.99.232.1 to 14.99.239.25414.99.239.2552,046
12714.99.240.0/2114.99.240.1 to 14.99.247.25414.99.247.2552,046
12814.99.248.0/2114.99.248.1 to 14.99.255.25414.99.255.2552,046
12914.100.0.0/2114.100.0.1 to 14.100.7.25414.100.7.2552,046
13014.100.8.0/2114.100.8.1 to 14.100.15.25414.100.15.2552,046
13114.100.16.0/2114.100.16.1 to 14.100.23.25414.100.23.2552,046
13214.100.24.0/2114.100.24.1 to 14.100.31.25414.100.31.2552,046
13314.100.32.0/2114.100.32.1 to 14.100.39.25414.100.39.2552,046
13414.100.40.0/2114.100.40.1 to 14.100.47.25414.100.47.2552,046
13514.100.48.0/2114.100.48.1 to 14.100.55.25414.100.55.2552,046
13614.100.56.0/2114.100.56.1 to 14.100.63.25414.100.63.2552,046
13714.100.64.0/2114.100.64.1 to 14.100.71.25414.100.71.2552,046
13814.100.72.0/2114.100.72.1 to 14.100.79.25414.100.79.2552,046
13914.100.80.0/2114.100.80.1 to 14.100.87.25414.100.87.2552,046
14014.100.88.0/2114.100.88.1 to 14.100.95.25414.100.95.2552,046
14114.100.96.0/2114.100.96.1 to 14.100.103.25414.100.103.2552,046
14214.100.104.0/2114.100.104.1 to 14.100.111.25414.100.111.2552,046
14314.100.112.0/2114.100.112.1 to 14.100.119.25414.100.119.2552,046
14414.100.120.0/2114.100.120.1 to 14.100.127.25414.100.127.2552,046
14514.100.128.0/2114.100.128.1 to 14.100.135.25414.100.135.2552,046
14614.100.136.0/2114.100.136.1 to 14.100.143.25414.100.143.2552,046
14714.100.144.0/2114.100.144.1 to 14.100.151.25414.100.151.2552,046
14814.100.152.0/2114.100.152.1 to 14.100.159.25414.100.159.2552,046
14914.100.160.0/2114.100.160.1 to 14.100.167.25414.100.167.2552,046
15014.100.168.0/2114.100.168.1 to 14.100.175.25414.100.175.2552,046
15114.100.176.0/2114.100.176.1 to 14.100.183.25414.100.183.2552,046
15214.100.184.0/2114.100.184.1 to 14.100.191.25414.100.191.2552,046
15314.100.192.0/2114.100.192.1 to 14.100.199.25414.100.199.2552,046
15414.100.200.0/2114.100.200.1 to 14.100.207.25414.100.207.2552,046
15514.100.208.0/2114.100.208.1 to 14.100.215.25414.100.215.2552,046
15614.100.216.0/2114.100.216.1 to 14.100.223.25414.100.223.2552,046
15714.100.224.0/2114.100.224.1 to 14.100.231.25414.100.231.2552,046
15814.100.232.0/2114.100.232.1 to 14.100.239.25414.100.239.2552,046
15914.100.240.0/2114.100.240.1 to 14.100.247.25414.100.247.2552,046
16014.100.248.0/2114.100.248.1 to 14.100.255.25414.100.255.2552,046
16114.101.0.0/2114.101.0.1 to 14.101.7.25414.101.7.2552,046
16214.101.8.0/2114.101.8.1 to 14.101.15.25414.101.15.2552,046
16314.101.16.0/2114.101.16.1 to 14.101.23.25414.101.23.2552,046
16414.101.24.0/2114.101.24.1 to 14.101.31.25414.101.31.2552,046
16514.101.32.0/2114.101.32.1 to 14.101.39.25414.101.39.2552,046
16614.101.40.0/2114.101.40.1 to 14.101.47.25414.101.47.2552,046
16714.101.48.0/2114.101.48.1 to 14.101.55.25414.101.55.2552,046
16814.101.56.0/2114.101.56.1 to 14.101.63.25414.101.63.2552,046
16914.101.64.0/2114.101.64.1 to 14.101.71.25414.101.71.2552,046
17014.101.72.0/2114.101.72.1 to 14.101.79.25414.101.79.2552,046
17114.101.80.0/2114.101.80.1 to 14.101.87.25414.101.87.2552,046
17214.101.88.0/2114.101.88.1 to 14.101.95.25414.101.95.2552,046
17314.101.96.0/2114.101.96.1 to 14.101.103.25414.101.103.2552,046
17414.101.104.0/2114.101.104.1 to 14.101.111.25414.101.111.2552,046
17514.101.112.0/2114.101.112.1 to 14.101.119.25414.101.119.2552,046
17614.101.120.0/2114.101.120.1 to 14.101.127.25414.101.127.2552,046
17714.101.128.0/2114.101.128.1 to 14.101.135.25414.101.135.2552,046
17814.101.136.0/2114.101.136.1 to 14.101.143.25414.101.143.2552,046
17914.101.144.0/2114.101.144.1 to 14.101.151.25414.101.151.2552,046
18014.101.152.0/2114.101.152.1 to 14.101.159.25414.101.159.2552,046
18114.101.160.0/2114.101.160.1 to 14.101.167.25414.101.167.2552,046
18214.101.168.0/2114.101.168.1 to 14.101.175.25414.101.175.2552,046
18314.101.176.0/2114.101.176.1 to 14.101.183.25414.101.183.2552,046
18414.101.184.0/2114.101.184.1 to 14.101.191.25414.101.191.2552,046
18514.101.192.0/2114.101.192.1 to 14.101.199.25414.101.199.2552,046
18614.101.200.0/2114.101.200.1 to 14.101.207.25414.101.207.2552,046
18714.101.208.0/2114.101.208.1 to 14.101.215.25414.101.215.2552,046
18814.101.216.0/2114.101.216.1 to 14.101.223.25414.101.223.2552,046
18914.101.224.0/2114.101.224.1 to 14.101.231.25414.101.231.2552,046
19014.101.232.0/2114.101.232.1 to 14.101.239.25414.101.239.2552,046
19114.101.240.0/2114.101.240.1 to 14.101.247.25414.101.247.2552,046
19214.101.248.0/2114.101.248.1 to 14.101.255.25414.101.255.2552,046
19314.102.0.0/2114.102.0.1 to 14.102.7.25414.102.7.2552,046
19414.102.8.0/2114.102.8.1 to 14.102.15.25414.102.15.2552,046
19514.102.16.0/2114.102.16.1 to 14.102.23.25414.102.23.2552,046
19614.102.24.0/2114.102.24.1 to 14.102.31.25414.102.31.2552,046
19714.102.32.0/2114.102.32.1 to 14.102.39.25414.102.39.2552,046
19814.102.40.0/2114.102.40.1 to 14.102.47.25414.102.47.2552,046
19914.102.48.0/2114.102.48.1 to 14.102.55.25414.102.55.2552,046
20014.102.56.0/2114.102.56.1 to 14.102.63.25414.102.63.2552,046
20114.102.64.0/2114.102.64.1 to 14.102.71.25414.102.71.2552,046
20214.102.72.0/2114.102.72.1 to 14.102.79.25414.102.79.2552,046
20314.102.80.0/2114.102.80.1 to 14.102.87.25414.102.87.2552,046
20414.102.88.0/2114.102.88.1 to 14.102.95.25414.102.95.2552,046
20514.102.96.0/2114.102.96.1 to 14.102.103.25414.102.103.2552,046
20614.102.104.0/2114.102.104.1 to 14.102.111.25414.102.111.2552,046
20714.102.112.0/2114.102.112.1 to 14.102.119.25414.102.119.2552,046
20814.102.120.0/2114.102.120.1 to 14.102.127.25414.102.127.2552,046
20914.102.128.0/2114.102.128.1 to 14.102.135.25414.102.135.2552,046
21014.102.136.0/2114.102.136.1 to 14.102.143.25414.102.143.2552,046
21114.102.144.0/2114.102.144.1 to 14.102.151.25414.102.151.2552,046
21214.102.152.0/2114.102.152.1 to 14.102.159.25414.102.159.2552,046
21314.102.160.0/2114.102.160.1 to 14.102.167.25414.102.167.2552,046
21414.102.168.0/2114.102.168.1 to 14.102.175.25414.102.175.2552,046
21514.102.176.0/2114.102.176.1 to 14.102.183.25414.102.183.2552,046
21614.102.184.0/2114.102.184.1 to 14.102.191.25414.102.191.2552,046
21714.102.192.0/2114.102.192.1 to 14.102.199.25414.102.199.2552,046
21814.102.200.0/2114.102.200.1 to 14.102.207.25414.102.207.2552,046
21914.102.208.0/2114.102.208.1 to 14.102.215.25414.102.215.2552,046
22014.102.216.0/2114.102.216.1 to 14.102.223.25414.102.223.2552,046
22114.102.224.0/2114.102.224.1 to 14.102.231.25414.102.231.2552,046
22214.102.232.0/2114.102.232.1 to 14.102.239.25414.102.239.2552,046
22314.102.240.0/2114.102.240.1 to 14.102.247.25414.102.247.2552,046
22414.102.248.0/2114.102.248.1 to 14.102.255.25414.102.255.2552,046
22514.103.0.0/2114.103.0.1 to 14.103.7.25414.103.7.2552,046
22614.103.8.0/2114.103.8.1 to 14.103.15.25414.103.15.2552,046
22714.103.16.0/2114.103.16.1 to 14.103.23.25414.103.23.2552,046
22814.103.24.0/2114.103.24.1 to 14.103.31.25414.103.31.2552,046
22914.103.32.0/2114.103.32.1 to 14.103.39.25414.103.39.2552,046
23014.103.40.0/2114.103.40.1 to 14.103.47.25414.103.47.2552,046
23114.103.48.0/2114.103.48.1 to 14.103.55.25414.103.55.2552,046
23214.103.56.0/2114.103.56.1 to 14.103.63.25414.103.63.2552,046
23314.103.64.0/2114.103.64.1 to 14.103.71.25414.103.71.2552,046
23414.103.72.0/2114.103.72.1 to 14.103.79.25414.103.79.2552,046
23514.103.80.0/2114.103.80.1 to 14.103.87.25414.103.87.2552,046
23614.103.88.0/2114.103.88.1 to 14.103.95.25414.103.95.2552,046
23714.103.96.0/2114.103.96.1 to 14.103.103.25414.103.103.2552,046
23814.103.104.0/2114.103.104.1 to 14.103.111.25414.103.111.2552,046
23914.103.112.0/2114.103.112.1 to 14.103.119.25414.103.119.2552,046
24014.103.120.0/2114.103.120.1 to 14.103.127.25414.103.127.2552,046
24114.103.128.0/2114.103.128.1 to 14.103.135.25414.103.135.2552,046
24214.103.136.0/2114.103.136.1 to 14.103.143.25414.103.143.2552,046
24314.103.144.0/2114.103.144.1 to 14.103.151.25414.103.151.2552,046
24414.103.152.0/2114.103.152.1 to 14.103.159.25414.103.159.2552,046
24514.103.160.0/2114.103.160.1 to 14.103.167.25414.103.167.2552,046
24614.103.168.0/2114.103.168.1 to 14.103.175.25414.103.175.2552,046
24714.103.176.0/2114.103.176.1 to 14.103.183.25414.103.183.2552,046
24814.103.184.0/2114.103.184.1 to 14.103.191.25414.103.191.2552,046
24914.103.192.0/2114.103.192.1 to 14.103.199.25414.103.199.2552,046
25014.103.200.0/2114.103.200.1 to 14.103.207.25414.103.207.2552,046
25114.103.208.0/2114.103.208.1 to 14.103.215.25414.103.215.2552,046
25214.103.216.0/2114.103.216.1 to 14.103.223.25414.103.223.2552,046
25314.103.224.0/2114.103.224.1 to 14.103.231.25414.103.231.2552,046
25414.103.232.0/2114.103.232.1 to 14.103.239.25414.103.239.2552,046
25514.103.240.0/2114.103.240.1 to 14.103.247.25414.103.247.2552,046
25614.103.248.0/2114.103.248.1 to 14.103.255.25414.103.255.2552,046

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.