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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.

Network14.128.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
14.128.0.0
Broadcast address
14.255.255.255
First usable
14.128.0.1
Last usable
14.255.255.254
Usable hosts
8,388,606 (8,388,608 less the network and broadcast addresses)
Subnet mask
255.128.0.0
Wildcard mask
0.127.255.255 (Cisco ACLs, OSPF)
Prefix length
/9
Type
Public public
Old class
A (default /8)
As numbers
Hex 0E800000 · Integer 243269632 to 251658239
Reverse DNS zones
128.14.in-addr.arpa
129.14.in-addr.arpa
130.14.in-addr.arpa
131.14.in-addr.arpa
132.14.in-addr.arpa
133.14.in-addr.arpa
134.14.in-addr.arpa
135.14.in-addr.arpa
136.14.in-addr.arpa
137.14.in-addr.arpa
138.14.in-addr.arpa
139.14.in-addr.arpa
140.14.in-addr.arpa
141.14.in-addr.arpa
142.14.in-addr.arpa
143.14.in-addr.arpa
and 112 more
/9 is not on a 8-bit boundary, so it takes 128 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00001110.10000000.00000000.0000000014.128.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network00001110.10000000.00000000.0000000014.128.0.0
Broadcast00001110.11111111.11111111.1111111114.255.255.255
Split into smaller subnets/17
/10 (2)/11 (4)/12 (8)/13 (16)/14 (32)/15 (64)/16 (128)/17 (256)/18 (512)/19 (1,024)/20 (2,048)/21 (4,096)

14.128.0.0/9 makes 256 subnets of /17.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
114.128.0.0/1714.128.0.1 to 14.128.127.25414.128.127.25532,766
214.128.128.0/1714.128.128.1 to 14.128.255.25414.128.255.25532,766
314.129.0.0/1714.129.0.1 to 14.129.127.25414.129.127.25532,766
414.129.128.0/1714.129.128.1 to 14.129.255.25414.129.255.25532,766
514.130.0.0/1714.130.0.1 to 14.130.127.25414.130.127.25532,766
614.130.128.0/1714.130.128.1 to 14.130.255.25414.130.255.25532,766
714.131.0.0/1714.131.0.1 to 14.131.127.25414.131.127.25532,766
814.131.128.0/1714.131.128.1 to 14.131.255.25414.131.255.25532,766
914.132.0.0/1714.132.0.1 to 14.132.127.25414.132.127.25532,766
1014.132.128.0/1714.132.128.1 to 14.132.255.25414.132.255.25532,766
1114.133.0.0/1714.133.0.1 to 14.133.127.25414.133.127.25532,766
1214.133.128.0/1714.133.128.1 to 14.133.255.25414.133.255.25532,766
1314.134.0.0/1714.134.0.1 to 14.134.127.25414.134.127.25532,766
1414.134.128.0/1714.134.128.1 to 14.134.255.25414.134.255.25532,766
1514.135.0.0/1714.135.0.1 to 14.135.127.25414.135.127.25532,766
1614.135.128.0/1714.135.128.1 to 14.135.255.25414.135.255.25532,766
1714.136.0.0/1714.136.0.1 to 14.136.127.25414.136.127.25532,766
1814.136.128.0/1714.136.128.1 to 14.136.255.25414.136.255.25532,766
1914.137.0.0/1714.137.0.1 to 14.137.127.25414.137.127.25532,766
2014.137.128.0/1714.137.128.1 to 14.137.255.25414.137.255.25532,766
2114.138.0.0/1714.138.0.1 to 14.138.127.25414.138.127.25532,766
2214.138.128.0/1714.138.128.1 to 14.138.255.25414.138.255.25532,766
2314.139.0.0/1714.139.0.1 to 14.139.127.25414.139.127.25532,766
2414.139.128.0/1714.139.128.1 to 14.139.255.25414.139.255.25532,766
2514.140.0.0/1714.140.0.1 to 14.140.127.25414.140.127.25532,766
2614.140.128.0/1714.140.128.1 to 14.140.255.25414.140.255.25532,766
2714.141.0.0/1714.141.0.1 to 14.141.127.25414.141.127.25532,766
2814.141.128.0/1714.141.128.1 to 14.141.255.25414.141.255.25532,766
2914.142.0.0/1714.142.0.1 to 14.142.127.25414.142.127.25532,766
3014.142.128.0/1714.142.128.1 to 14.142.255.25414.142.255.25532,766
3114.143.0.0/1714.143.0.1 to 14.143.127.25414.143.127.25532,766
3214.143.128.0/1714.143.128.1 to 14.143.255.25414.143.255.25532,766
3314.144.0.0/1714.144.0.1 to 14.144.127.25414.144.127.25532,766
3414.144.128.0/1714.144.128.1 to 14.144.255.25414.144.255.25532,766
3514.145.0.0/1714.145.0.1 to 14.145.127.25414.145.127.25532,766
3614.145.128.0/1714.145.128.1 to 14.145.255.25414.145.255.25532,766
3714.146.0.0/1714.146.0.1 to 14.146.127.25414.146.127.25532,766
3814.146.128.0/1714.146.128.1 to 14.146.255.25414.146.255.25532,766
3914.147.0.0/1714.147.0.1 to 14.147.127.25414.147.127.25532,766
4014.147.128.0/1714.147.128.1 to 14.147.255.25414.147.255.25532,766
4114.148.0.0/1714.148.0.1 to 14.148.127.25414.148.127.25532,766
4214.148.128.0/1714.148.128.1 to 14.148.255.25414.148.255.25532,766
4314.149.0.0/1714.149.0.1 to 14.149.127.25414.149.127.25532,766
4414.149.128.0/1714.149.128.1 to 14.149.255.25414.149.255.25532,766
4514.150.0.0/1714.150.0.1 to 14.150.127.25414.150.127.25532,766
4614.150.128.0/1714.150.128.1 to 14.150.255.25414.150.255.25532,766
4714.151.0.0/1714.151.0.1 to 14.151.127.25414.151.127.25532,766
4814.151.128.0/1714.151.128.1 to 14.151.255.25414.151.255.25532,766
4914.152.0.0/1714.152.0.1 to 14.152.127.25414.152.127.25532,766
5014.152.128.0/1714.152.128.1 to 14.152.255.25414.152.255.25532,766
5114.153.0.0/1714.153.0.1 to 14.153.127.25414.153.127.25532,766
5214.153.128.0/1714.153.128.1 to 14.153.255.25414.153.255.25532,766
5314.154.0.0/1714.154.0.1 to 14.154.127.25414.154.127.25532,766
5414.154.128.0/1714.154.128.1 to 14.154.255.25414.154.255.25532,766
5514.155.0.0/1714.155.0.1 to 14.155.127.25414.155.127.25532,766
5614.155.128.0/1714.155.128.1 to 14.155.255.25414.155.255.25532,766
5714.156.0.0/1714.156.0.1 to 14.156.127.25414.156.127.25532,766
5814.156.128.0/1714.156.128.1 to 14.156.255.25414.156.255.25532,766
5914.157.0.0/1714.157.0.1 to 14.157.127.25414.157.127.25532,766
6014.157.128.0/1714.157.128.1 to 14.157.255.25414.157.255.25532,766
6114.158.0.0/1714.158.0.1 to 14.158.127.25414.158.127.25532,766
6214.158.128.0/1714.158.128.1 to 14.158.255.25414.158.255.25532,766
6314.159.0.0/1714.159.0.1 to 14.159.127.25414.159.127.25532,766
6414.159.128.0/1714.159.128.1 to 14.159.255.25414.159.255.25532,766
6514.160.0.0/1714.160.0.1 to 14.160.127.25414.160.127.25532,766
6614.160.128.0/1714.160.128.1 to 14.160.255.25414.160.255.25532,766
6714.161.0.0/1714.161.0.1 to 14.161.127.25414.161.127.25532,766
6814.161.128.0/1714.161.128.1 to 14.161.255.25414.161.255.25532,766
6914.162.0.0/1714.162.0.1 to 14.162.127.25414.162.127.25532,766
7014.162.128.0/1714.162.128.1 to 14.162.255.25414.162.255.25532,766
7114.163.0.0/1714.163.0.1 to 14.163.127.25414.163.127.25532,766
7214.163.128.0/1714.163.128.1 to 14.163.255.25414.163.255.25532,766
7314.164.0.0/1714.164.0.1 to 14.164.127.25414.164.127.25532,766
7414.164.128.0/1714.164.128.1 to 14.164.255.25414.164.255.25532,766
7514.165.0.0/1714.165.0.1 to 14.165.127.25414.165.127.25532,766
7614.165.128.0/1714.165.128.1 to 14.165.255.25414.165.255.25532,766
7714.166.0.0/1714.166.0.1 to 14.166.127.25414.166.127.25532,766
7814.166.128.0/1714.166.128.1 to 14.166.255.25414.166.255.25532,766
7914.167.0.0/1714.167.0.1 to 14.167.127.25414.167.127.25532,766
8014.167.128.0/1714.167.128.1 to 14.167.255.25414.167.255.25532,766
8114.168.0.0/1714.168.0.1 to 14.168.127.25414.168.127.25532,766
8214.168.128.0/1714.168.128.1 to 14.168.255.25414.168.255.25532,766
8314.169.0.0/1714.169.0.1 to 14.169.127.25414.169.127.25532,766
8414.169.128.0/1714.169.128.1 to 14.169.255.25414.169.255.25532,766
8514.170.0.0/1714.170.0.1 to 14.170.127.25414.170.127.25532,766
8614.170.128.0/1714.170.128.1 to 14.170.255.25414.170.255.25532,766
8714.171.0.0/1714.171.0.1 to 14.171.127.25414.171.127.25532,766
8814.171.128.0/1714.171.128.1 to 14.171.255.25414.171.255.25532,766
8914.172.0.0/1714.172.0.1 to 14.172.127.25414.172.127.25532,766
9014.172.128.0/1714.172.128.1 to 14.172.255.25414.172.255.25532,766
9114.173.0.0/1714.173.0.1 to 14.173.127.25414.173.127.25532,766
9214.173.128.0/1714.173.128.1 to 14.173.255.25414.173.255.25532,766
9314.174.0.0/1714.174.0.1 to 14.174.127.25414.174.127.25532,766
9414.174.128.0/1714.174.128.1 to 14.174.255.25414.174.255.25532,766
9514.175.0.0/1714.175.0.1 to 14.175.127.25414.175.127.25532,766
9614.175.128.0/1714.175.128.1 to 14.175.255.25414.175.255.25532,766
9714.176.0.0/1714.176.0.1 to 14.176.127.25414.176.127.25532,766
9814.176.128.0/1714.176.128.1 to 14.176.255.25414.176.255.25532,766
9914.177.0.0/1714.177.0.1 to 14.177.127.25414.177.127.25532,766
10014.177.128.0/1714.177.128.1 to 14.177.255.25414.177.255.25532,766
10114.178.0.0/1714.178.0.1 to 14.178.127.25414.178.127.25532,766
10214.178.128.0/1714.178.128.1 to 14.178.255.25414.178.255.25532,766
10314.179.0.0/1714.179.0.1 to 14.179.127.25414.179.127.25532,766
10414.179.128.0/1714.179.128.1 to 14.179.255.25414.179.255.25532,766
10514.180.0.0/1714.180.0.1 to 14.180.127.25414.180.127.25532,766
10614.180.128.0/1714.180.128.1 to 14.180.255.25414.180.255.25532,766
10714.181.0.0/1714.181.0.1 to 14.181.127.25414.181.127.25532,766
10814.181.128.0/1714.181.128.1 to 14.181.255.25414.181.255.25532,766
10914.182.0.0/1714.182.0.1 to 14.182.127.25414.182.127.25532,766
11014.182.128.0/1714.182.128.1 to 14.182.255.25414.182.255.25532,766
11114.183.0.0/1714.183.0.1 to 14.183.127.25414.183.127.25532,766
11214.183.128.0/1714.183.128.1 to 14.183.255.25414.183.255.25532,766
11314.184.0.0/1714.184.0.1 to 14.184.127.25414.184.127.25532,766
11414.184.128.0/1714.184.128.1 to 14.184.255.25414.184.255.25532,766
11514.185.0.0/1714.185.0.1 to 14.185.127.25414.185.127.25532,766
11614.185.128.0/1714.185.128.1 to 14.185.255.25414.185.255.25532,766
11714.186.0.0/1714.186.0.1 to 14.186.127.25414.186.127.25532,766
11814.186.128.0/1714.186.128.1 to 14.186.255.25414.186.255.25532,766
11914.187.0.0/1714.187.0.1 to 14.187.127.25414.187.127.25532,766
12014.187.128.0/1714.187.128.1 to 14.187.255.25414.187.255.25532,766
12114.188.0.0/1714.188.0.1 to 14.188.127.25414.188.127.25532,766
12214.188.128.0/1714.188.128.1 to 14.188.255.25414.188.255.25532,766
12314.189.0.0/1714.189.0.1 to 14.189.127.25414.189.127.25532,766
12414.189.128.0/1714.189.128.1 to 14.189.255.25414.189.255.25532,766
12514.190.0.0/1714.190.0.1 to 14.190.127.25414.190.127.25532,766
12614.190.128.0/1714.190.128.1 to 14.190.255.25414.190.255.25532,766
12714.191.0.0/1714.191.0.1 to 14.191.127.25414.191.127.25532,766
12814.191.128.0/1714.191.128.1 to 14.191.255.25414.191.255.25532,766
12914.192.0.0/1714.192.0.1 to 14.192.127.25414.192.127.25532,766
13014.192.128.0/1714.192.128.1 to 14.192.255.25414.192.255.25532,766
13114.193.0.0/1714.193.0.1 to 14.193.127.25414.193.127.25532,766
13214.193.128.0/1714.193.128.1 to 14.193.255.25414.193.255.25532,766
13314.194.0.0/1714.194.0.1 to 14.194.127.25414.194.127.25532,766
13414.194.128.0/1714.194.128.1 to 14.194.255.25414.194.255.25532,766
13514.195.0.0/1714.195.0.1 to 14.195.127.25414.195.127.25532,766
13614.195.128.0/1714.195.128.1 to 14.195.255.25414.195.255.25532,766
13714.196.0.0/1714.196.0.1 to 14.196.127.25414.196.127.25532,766
13814.196.128.0/1714.196.128.1 to 14.196.255.25414.196.255.25532,766
13914.197.0.0/1714.197.0.1 to 14.197.127.25414.197.127.25532,766
14014.197.128.0/1714.197.128.1 to 14.197.255.25414.197.255.25532,766
14114.198.0.0/1714.198.0.1 to 14.198.127.25414.198.127.25532,766
14214.198.128.0/1714.198.128.1 to 14.198.255.25414.198.255.25532,766
14314.199.0.0/1714.199.0.1 to 14.199.127.25414.199.127.25532,766
14414.199.128.0/1714.199.128.1 to 14.199.255.25414.199.255.25532,766
14514.200.0.0/1714.200.0.1 to 14.200.127.25414.200.127.25532,766
14614.200.128.0/1714.200.128.1 to 14.200.255.25414.200.255.25532,766
14714.201.0.0/1714.201.0.1 to 14.201.127.25414.201.127.25532,766
14814.201.128.0/1714.201.128.1 to 14.201.255.25414.201.255.25532,766
14914.202.0.0/1714.202.0.1 to 14.202.127.25414.202.127.25532,766
15014.202.128.0/1714.202.128.1 to 14.202.255.25414.202.255.25532,766
15114.203.0.0/1714.203.0.1 to 14.203.127.25414.203.127.25532,766
15214.203.128.0/1714.203.128.1 to 14.203.255.25414.203.255.25532,766
15314.204.0.0/1714.204.0.1 to 14.204.127.25414.204.127.25532,766
15414.204.128.0/1714.204.128.1 to 14.204.255.25414.204.255.25532,766
15514.205.0.0/1714.205.0.1 to 14.205.127.25414.205.127.25532,766
15614.205.128.0/1714.205.128.1 to 14.205.255.25414.205.255.25532,766
15714.206.0.0/1714.206.0.1 to 14.206.127.25414.206.127.25532,766
15814.206.128.0/1714.206.128.1 to 14.206.255.25414.206.255.25532,766
15914.207.0.0/1714.207.0.1 to 14.207.127.25414.207.127.25532,766
16014.207.128.0/1714.207.128.1 to 14.207.255.25414.207.255.25532,766
16114.208.0.0/1714.208.0.1 to 14.208.127.25414.208.127.25532,766
16214.208.128.0/1714.208.128.1 to 14.208.255.25414.208.255.25532,766
16314.209.0.0/1714.209.0.1 to 14.209.127.25414.209.127.25532,766
16414.209.128.0/1714.209.128.1 to 14.209.255.25414.209.255.25532,766
16514.210.0.0/1714.210.0.1 to 14.210.127.25414.210.127.25532,766
16614.210.128.0/1714.210.128.1 to 14.210.255.25414.210.255.25532,766
16714.211.0.0/1714.211.0.1 to 14.211.127.25414.211.127.25532,766
16814.211.128.0/1714.211.128.1 to 14.211.255.25414.211.255.25532,766
16914.212.0.0/1714.212.0.1 to 14.212.127.25414.212.127.25532,766
17014.212.128.0/1714.212.128.1 to 14.212.255.25414.212.255.25532,766
17114.213.0.0/1714.213.0.1 to 14.213.127.25414.213.127.25532,766
17214.213.128.0/1714.213.128.1 to 14.213.255.25414.213.255.25532,766
17314.214.0.0/1714.214.0.1 to 14.214.127.25414.214.127.25532,766
17414.214.128.0/1714.214.128.1 to 14.214.255.25414.214.255.25532,766
17514.215.0.0/1714.215.0.1 to 14.215.127.25414.215.127.25532,766
17614.215.128.0/1714.215.128.1 to 14.215.255.25414.215.255.25532,766
17714.216.0.0/1714.216.0.1 to 14.216.127.25414.216.127.25532,766
17814.216.128.0/1714.216.128.1 to 14.216.255.25414.216.255.25532,766
17914.217.0.0/1714.217.0.1 to 14.217.127.25414.217.127.25532,766
18014.217.128.0/1714.217.128.1 to 14.217.255.25414.217.255.25532,766
18114.218.0.0/1714.218.0.1 to 14.218.127.25414.218.127.25532,766
18214.218.128.0/1714.218.128.1 to 14.218.255.25414.218.255.25532,766
18314.219.0.0/1714.219.0.1 to 14.219.127.25414.219.127.25532,766
18414.219.128.0/1714.219.128.1 to 14.219.255.25414.219.255.25532,766
18514.220.0.0/1714.220.0.1 to 14.220.127.25414.220.127.25532,766
18614.220.128.0/1714.220.128.1 to 14.220.255.25414.220.255.25532,766
18714.221.0.0/1714.221.0.1 to 14.221.127.25414.221.127.25532,766
18814.221.128.0/1714.221.128.1 to 14.221.255.25414.221.255.25532,766
18914.222.0.0/1714.222.0.1 to 14.222.127.25414.222.127.25532,766
19014.222.128.0/1714.222.128.1 to 14.222.255.25414.222.255.25532,766
19114.223.0.0/1714.223.0.1 to 14.223.127.25414.223.127.25532,766
19214.223.128.0/1714.223.128.1 to 14.223.255.25414.223.255.25532,766
19314.224.0.0/1714.224.0.1 to 14.224.127.25414.224.127.25532,766
19414.224.128.0/1714.224.128.1 to 14.224.255.25414.224.255.25532,766
19514.225.0.0/1714.225.0.1 to 14.225.127.25414.225.127.25532,766
19614.225.128.0/1714.225.128.1 to 14.225.255.25414.225.255.25532,766
19714.226.0.0/1714.226.0.1 to 14.226.127.25414.226.127.25532,766
19814.226.128.0/1714.226.128.1 to 14.226.255.25414.226.255.25532,766
19914.227.0.0/1714.227.0.1 to 14.227.127.25414.227.127.25532,766
20014.227.128.0/1714.227.128.1 to 14.227.255.25414.227.255.25532,766
20114.228.0.0/1714.228.0.1 to 14.228.127.25414.228.127.25532,766
20214.228.128.0/1714.228.128.1 to 14.228.255.25414.228.255.25532,766
20314.229.0.0/1714.229.0.1 to 14.229.127.25414.229.127.25532,766
20414.229.128.0/1714.229.128.1 to 14.229.255.25414.229.255.25532,766
20514.230.0.0/1714.230.0.1 to 14.230.127.25414.230.127.25532,766
20614.230.128.0/1714.230.128.1 to 14.230.255.25414.230.255.25532,766
20714.231.0.0/1714.231.0.1 to 14.231.127.25414.231.127.25532,766
20814.231.128.0/1714.231.128.1 to 14.231.255.25414.231.255.25532,766
20914.232.0.0/1714.232.0.1 to 14.232.127.25414.232.127.25532,766
21014.232.128.0/1714.232.128.1 to 14.232.255.25414.232.255.25532,766
21114.233.0.0/1714.233.0.1 to 14.233.127.25414.233.127.25532,766
21214.233.128.0/1714.233.128.1 to 14.233.255.25414.233.255.25532,766
21314.234.0.0/1714.234.0.1 to 14.234.127.25414.234.127.25532,766
21414.234.128.0/1714.234.128.1 to 14.234.255.25414.234.255.25532,766
21514.235.0.0/1714.235.0.1 to 14.235.127.25414.235.127.25532,766
21614.235.128.0/1714.235.128.1 to 14.235.255.25414.235.255.25532,766
21714.236.0.0/1714.236.0.1 to 14.236.127.25414.236.127.25532,766
21814.236.128.0/1714.236.128.1 to 14.236.255.25414.236.255.25532,766
21914.237.0.0/1714.237.0.1 to 14.237.127.25414.237.127.25532,766
22014.237.128.0/1714.237.128.1 to 14.237.255.25414.237.255.25532,766
22114.238.0.0/1714.238.0.1 to 14.238.127.25414.238.127.25532,766
22214.238.128.0/1714.238.128.1 to 14.238.255.25414.238.255.25532,766
22314.239.0.0/1714.239.0.1 to 14.239.127.25414.239.127.25532,766
22414.239.128.0/1714.239.128.1 to 14.239.255.25414.239.255.25532,766
22514.240.0.0/1714.240.0.1 to 14.240.127.25414.240.127.25532,766
22614.240.128.0/1714.240.128.1 to 14.240.255.25414.240.255.25532,766
22714.241.0.0/1714.241.0.1 to 14.241.127.25414.241.127.25532,766
22814.241.128.0/1714.241.128.1 to 14.241.255.25414.241.255.25532,766
22914.242.0.0/1714.242.0.1 to 14.242.127.25414.242.127.25532,766
23014.242.128.0/1714.242.128.1 to 14.242.255.25414.242.255.25532,766
23114.243.0.0/1714.243.0.1 to 14.243.127.25414.243.127.25532,766
23214.243.128.0/1714.243.128.1 to 14.243.255.25414.243.255.25532,766
23314.244.0.0/1714.244.0.1 to 14.244.127.25414.244.127.25532,766
23414.244.128.0/1714.244.128.1 to 14.244.255.25414.244.255.25532,766
23514.245.0.0/1714.245.0.1 to 14.245.127.25414.245.127.25532,766
23614.245.128.0/1714.245.128.1 to 14.245.255.25414.245.255.25532,766
23714.246.0.0/1714.246.0.1 to 14.246.127.25414.246.127.25532,766
23814.246.128.0/1714.246.128.1 to 14.246.255.25414.246.255.25532,766
23914.247.0.0/1714.247.0.1 to 14.247.127.25414.247.127.25532,766
24014.247.128.0/1714.247.128.1 to 14.247.255.25414.247.255.25532,766
24114.248.0.0/1714.248.0.1 to 14.248.127.25414.248.127.25532,766
24214.248.128.0/1714.248.128.1 to 14.248.255.25414.248.255.25532,766
24314.249.0.0/1714.249.0.1 to 14.249.127.25414.249.127.25532,766
24414.249.128.0/1714.249.128.1 to 14.249.255.25414.249.255.25532,766
24514.250.0.0/1714.250.0.1 to 14.250.127.25414.250.127.25532,766
24614.250.128.0/1714.250.128.1 to 14.250.255.25414.250.255.25532,766
24714.251.0.0/1714.251.0.1 to 14.251.127.25414.251.127.25532,766
24814.251.128.0/1714.251.128.1 to 14.251.255.25414.251.255.25532,766
24914.252.0.0/1714.252.0.1 to 14.252.127.25414.252.127.25532,766
25014.252.128.0/1714.252.128.1 to 14.252.255.25414.252.255.25532,766
25114.253.0.0/1714.253.0.1 to 14.253.127.25414.253.127.25532,766
25214.253.128.0/1714.253.128.1 to 14.253.255.25414.253.255.25532,766
25314.254.0.0/1714.254.0.1 to 14.254.127.25414.254.127.25532,766
25414.254.128.0/1714.254.128.1 to 14.254.255.25414.254.255.25532,766
25514.255.0.0/1714.255.0.1 to 14.255.127.25414.255.127.25532,766
25614.255.128.0/1714.255.128.1 to 14.255.255.25414.255.255.25532,766

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.