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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.

Network64.20.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
64.20.0.0
Broadcast address
64.23.255.255
First usable
64.20.0.1
Last usable
64.23.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
A (default /8)
As numbers
Hex 40140000 · Integer 1075052544 to 1075314687
Reverse DNS zones
20.64.in-addr.arpa
21.64.in-addr.arpa
22.64.in-addr.arpa
23.64.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01000000.00010100.00000000.0000000064.20.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01000000.00010100.00000000.0000000064.20.0.0
Broadcast01000000.00010111.11111111.1111111164.23.255.255
Split into smaller subnets/22
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

64.20.0.0/14 makes 256 subnets of /22.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
164.20.0.0/2264.20.0.1 to 64.20.3.25464.20.3.2551,022
264.20.4.0/2264.20.4.1 to 64.20.7.25464.20.7.2551,022
364.20.8.0/2264.20.8.1 to 64.20.11.25464.20.11.2551,022
464.20.12.0/2264.20.12.1 to 64.20.15.25464.20.15.2551,022
564.20.16.0/2264.20.16.1 to 64.20.19.25464.20.19.2551,022
664.20.20.0/2264.20.20.1 to 64.20.23.25464.20.23.2551,022
764.20.24.0/2264.20.24.1 to 64.20.27.25464.20.27.2551,022
864.20.28.0/2264.20.28.1 to 64.20.31.25464.20.31.2551,022
964.20.32.0/2264.20.32.1 to 64.20.35.25464.20.35.2551,022
1064.20.36.0/2264.20.36.1 to 64.20.39.25464.20.39.2551,022
1164.20.40.0/2264.20.40.1 to 64.20.43.25464.20.43.2551,022
1264.20.44.0/2264.20.44.1 to 64.20.47.25464.20.47.2551,022
1364.20.48.0/2264.20.48.1 to 64.20.51.25464.20.51.2551,022
1464.20.52.0/2264.20.52.1 to 64.20.55.25464.20.55.2551,022
1564.20.56.0/2264.20.56.1 to 64.20.59.25464.20.59.2551,022
1664.20.60.0/2264.20.60.1 to 64.20.63.25464.20.63.2551,022
1764.20.64.0/2264.20.64.1 to 64.20.67.25464.20.67.2551,022
1864.20.68.0/2264.20.68.1 to 64.20.71.25464.20.71.2551,022
1964.20.72.0/2264.20.72.1 to 64.20.75.25464.20.75.2551,022
2064.20.76.0/2264.20.76.1 to 64.20.79.25464.20.79.2551,022
2164.20.80.0/2264.20.80.1 to 64.20.83.25464.20.83.2551,022
2264.20.84.0/2264.20.84.1 to 64.20.87.25464.20.87.2551,022
2364.20.88.0/2264.20.88.1 to 64.20.91.25464.20.91.2551,022
2464.20.92.0/2264.20.92.1 to 64.20.95.25464.20.95.2551,022
2564.20.96.0/2264.20.96.1 to 64.20.99.25464.20.99.2551,022
2664.20.100.0/2264.20.100.1 to 64.20.103.25464.20.103.2551,022
2764.20.104.0/2264.20.104.1 to 64.20.107.25464.20.107.2551,022
2864.20.108.0/2264.20.108.1 to 64.20.111.25464.20.111.2551,022
2964.20.112.0/2264.20.112.1 to 64.20.115.25464.20.115.2551,022
3064.20.116.0/2264.20.116.1 to 64.20.119.25464.20.119.2551,022
3164.20.120.0/2264.20.120.1 to 64.20.123.25464.20.123.2551,022
3264.20.124.0/2264.20.124.1 to 64.20.127.25464.20.127.2551,022
3364.20.128.0/2264.20.128.1 to 64.20.131.25464.20.131.2551,022
3464.20.132.0/2264.20.132.1 to 64.20.135.25464.20.135.2551,022
3564.20.136.0/2264.20.136.1 to 64.20.139.25464.20.139.2551,022
3664.20.140.0/2264.20.140.1 to 64.20.143.25464.20.143.2551,022
3764.20.144.0/2264.20.144.1 to 64.20.147.25464.20.147.2551,022
3864.20.148.0/2264.20.148.1 to 64.20.151.25464.20.151.2551,022
3964.20.152.0/2264.20.152.1 to 64.20.155.25464.20.155.2551,022
4064.20.156.0/2264.20.156.1 to 64.20.159.25464.20.159.2551,022
4164.20.160.0/2264.20.160.1 to 64.20.163.25464.20.163.2551,022
4264.20.164.0/2264.20.164.1 to 64.20.167.25464.20.167.2551,022
4364.20.168.0/2264.20.168.1 to 64.20.171.25464.20.171.2551,022
4464.20.172.0/2264.20.172.1 to 64.20.175.25464.20.175.2551,022
4564.20.176.0/2264.20.176.1 to 64.20.179.25464.20.179.2551,022
4664.20.180.0/2264.20.180.1 to 64.20.183.25464.20.183.2551,022
4764.20.184.0/2264.20.184.1 to 64.20.187.25464.20.187.2551,022
4864.20.188.0/2264.20.188.1 to 64.20.191.25464.20.191.2551,022
4964.20.192.0/2264.20.192.1 to 64.20.195.25464.20.195.2551,022
5064.20.196.0/2264.20.196.1 to 64.20.199.25464.20.199.2551,022
5164.20.200.0/2264.20.200.1 to 64.20.203.25464.20.203.2551,022
5264.20.204.0/2264.20.204.1 to 64.20.207.25464.20.207.2551,022
5364.20.208.0/2264.20.208.1 to 64.20.211.25464.20.211.2551,022
5464.20.212.0/2264.20.212.1 to 64.20.215.25464.20.215.2551,022
5564.20.216.0/2264.20.216.1 to 64.20.219.25464.20.219.2551,022
5664.20.220.0/2264.20.220.1 to 64.20.223.25464.20.223.2551,022
5764.20.224.0/2264.20.224.1 to 64.20.227.25464.20.227.2551,022
5864.20.228.0/2264.20.228.1 to 64.20.231.25464.20.231.2551,022
5964.20.232.0/2264.20.232.1 to 64.20.235.25464.20.235.2551,022
6064.20.236.0/2264.20.236.1 to 64.20.239.25464.20.239.2551,022
6164.20.240.0/2264.20.240.1 to 64.20.243.25464.20.243.2551,022
6264.20.244.0/2264.20.244.1 to 64.20.247.25464.20.247.2551,022
6364.20.248.0/2264.20.248.1 to 64.20.251.25464.20.251.2551,022
6464.20.252.0/2264.20.252.1 to 64.20.255.25464.20.255.2551,022
6564.21.0.0/2264.21.0.1 to 64.21.3.25464.21.3.2551,022
6664.21.4.0/2264.21.4.1 to 64.21.7.25464.21.7.2551,022
6764.21.8.0/2264.21.8.1 to 64.21.11.25464.21.11.2551,022
6864.21.12.0/2264.21.12.1 to 64.21.15.25464.21.15.2551,022
6964.21.16.0/2264.21.16.1 to 64.21.19.25464.21.19.2551,022
7064.21.20.0/2264.21.20.1 to 64.21.23.25464.21.23.2551,022
7164.21.24.0/2264.21.24.1 to 64.21.27.25464.21.27.2551,022
7264.21.28.0/2264.21.28.1 to 64.21.31.25464.21.31.2551,022
7364.21.32.0/2264.21.32.1 to 64.21.35.25464.21.35.2551,022
7464.21.36.0/2264.21.36.1 to 64.21.39.25464.21.39.2551,022
7564.21.40.0/2264.21.40.1 to 64.21.43.25464.21.43.2551,022
7664.21.44.0/2264.21.44.1 to 64.21.47.25464.21.47.2551,022
7764.21.48.0/2264.21.48.1 to 64.21.51.25464.21.51.2551,022
7864.21.52.0/2264.21.52.1 to 64.21.55.25464.21.55.2551,022
7964.21.56.0/2264.21.56.1 to 64.21.59.25464.21.59.2551,022
8064.21.60.0/2264.21.60.1 to 64.21.63.25464.21.63.2551,022
8164.21.64.0/2264.21.64.1 to 64.21.67.25464.21.67.2551,022
8264.21.68.0/2264.21.68.1 to 64.21.71.25464.21.71.2551,022
8364.21.72.0/2264.21.72.1 to 64.21.75.25464.21.75.2551,022
8464.21.76.0/2264.21.76.1 to 64.21.79.25464.21.79.2551,022
8564.21.80.0/2264.21.80.1 to 64.21.83.25464.21.83.2551,022
8664.21.84.0/2264.21.84.1 to 64.21.87.25464.21.87.2551,022
8764.21.88.0/2264.21.88.1 to 64.21.91.25464.21.91.2551,022
8864.21.92.0/2264.21.92.1 to 64.21.95.25464.21.95.2551,022
8964.21.96.0/2264.21.96.1 to 64.21.99.25464.21.99.2551,022
9064.21.100.0/2264.21.100.1 to 64.21.103.25464.21.103.2551,022
9164.21.104.0/2264.21.104.1 to 64.21.107.25464.21.107.2551,022
9264.21.108.0/2264.21.108.1 to 64.21.111.25464.21.111.2551,022
9364.21.112.0/2264.21.112.1 to 64.21.115.25464.21.115.2551,022
9464.21.116.0/2264.21.116.1 to 64.21.119.25464.21.119.2551,022
9564.21.120.0/2264.21.120.1 to 64.21.123.25464.21.123.2551,022
9664.21.124.0/2264.21.124.1 to 64.21.127.25464.21.127.2551,022
9764.21.128.0/2264.21.128.1 to 64.21.131.25464.21.131.2551,022
9864.21.132.0/2264.21.132.1 to 64.21.135.25464.21.135.2551,022
9964.21.136.0/2264.21.136.1 to 64.21.139.25464.21.139.2551,022
10064.21.140.0/2264.21.140.1 to 64.21.143.25464.21.143.2551,022
10164.21.144.0/2264.21.144.1 to 64.21.147.25464.21.147.2551,022
10264.21.148.0/2264.21.148.1 to 64.21.151.25464.21.151.2551,022
10364.21.152.0/2264.21.152.1 to 64.21.155.25464.21.155.2551,022
10464.21.156.0/2264.21.156.1 to 64.21.159.25464.21.159.2551,022
10564.21.160.0/2264.21.160.1 to 64.21.163.25464.21.163.2551,022
10664.21.164.0/2264.21.164.1 to 64.21.167.25464.21.167.2551,022
10764.21.168.0/2264.21.168.1 to 64.21.171.25464.21.171.2551,022
10864.21.172.0/2264.21.172.1 to 64.21.175.25464.21.175.2551,022
10964.21.176.0/2264.21.176.1 to 64.21.179.25464.21.179.2551,022
11064.21.180.0/2264.21.180.1 to 64.21.183.25464.21.183.2551,022
11164.21.184.0/2264.21.184.1 to 64.21.187.25464.21.187.2551,022
11264.21.188.0/2264.21.188.1 to 64.21.191.25464.21.191.2551,022
11364.21.192.0/2264.21.192.1 to 64.21.195.25464.21.195.2551,022
11464.21.196.0/2264.21.196.1 to 64.21.199.25464.21.199.2551,022
11564.21.200.0/2264.21.200.1 to 64.21.203.25464.21.203.2551,022
11664.21.204.0/2264.21.204.1 to 64.21.207.25464.21.207.2551,022
11764.21.208.0/2264.21.208.1 to 64.21.211.25464.21.211.2551,022
11864.21.212.0/2264.21.212.1 to 64.21.215.25464.21.215.2551,022
11964.21.216.0/2264.21.216.1 to 64.21.219.25464.21.219.2551,022
12064.21.220.0/2264.21.220.1 to 64.21.223.25464.21.223.2551,022
12164.21.224.0/2264.21.224.1 to 64.21.227.25464.21.227.2551,022
12264.21.228.0/2264.21.228.1 to 64.21.231.25464.21.231.2551,022
12364.21.232.0/2264.21.232.1 to 64.21.235.25464.21.235.2551,022
12464.21.236.0/2264.21.236.1 to 64.21.239.25464.21.239.2551,022
12564.21.240.0/2264.21.240.1 to 64.21.243.25464.21.243.2551,022
12664.21.244.0/2264.21.244.1 to 64.21.247.25464.21.247.2551,022
12764.21.248.0/2264.21.248.1 to 64.21.251.25464.21.251.2551,022
12864.21.252.0/2264.21.252.1 to 64.21.255.25464.21.255.2551,022
12964.22.0.0/2264.22.0.1 to 64.22.3.25464.22.3.2551,022
13064.22.4.0/2264.22.4.1 to 64.22.7.25464.22.7.2551,022
13164.22.8.0/2264.22.8.1 to 64.22.11.25464.22.11.2551,022
13264.22.12.0/2264.22.12.1 to 64.22.15.25464.22.15.2551,022
13364.22.16.0/2264.22.16.1 to 64.22.19.25464.22.19.2551,022
13464.22.20.0/2264.22.20.1 to 64.22.23.25464.22.23.2551,022
13564.22.24.0/2264.22.24.1 to 64.22.27.25464.22.27.2551,022
13664.22.28.0/2264.22.28.1 to 64.22.31.25464.22.31.2551,022
13764.22.32.0/2264.22.32.1 to 64.22.35.25464.22.35.2551,022
13864.22.36.0/2264.22.36.1 to 64.22.39.25464.22.39.2551,022
13964.22.40.0/2264.22.40.1 to 64.22.43.25464.22.43.2551,022
14064.22.44.0/2264.22.44.1 to 64.22.47.25464.22.47.2551,022
14164.22.48.0/2264.22.48.1 to 64.22.51.25464.22.51.2551,022
14264.22.52.0/2264.22.52.1 to 64.22.55.25464.22.55.2551,022
14364.22.56.0/2264.22.56.1 to 64.22.59.25464.22.59.2551,022
14464.22.60.0/2264.22.60.1 to 64.22.63.25464.22.63.2551,022
14564.22.64.0/2264.22.64.1 to 64.22.67.25464.22.67.2551,022
14664.22.68.0/2264.22.68.1 to 64.22.71.25464.22.71.2551,022
14764.22.72.0/2264.22.72.1 to 64.22.75.25464.22.75.2551,022
14864.22.76.0/2264.22.76.1 to 64.22.79.25464.22.79.2551,022
14964.22.80.0/2264.22.80.1 to 64.22.83.25464.22.83.2551,022
15064.22.84.0/2264.22.84.1 to 64.22.87.25464.22.87.2551,022
15164.22.88.0/2264.22.88.1 to 64.22.91.25464.22.91.2551,022
15264.22.92.0/2264.22.92.1 to 64.22.95.25464.22.95.2551,022
15364.22.96.0/2264.22.96.1 to 64.22.99.25464.22.99.2551,022
15464.22.100.0/2264.22.100.1 to 64.22.103.25464.22.103.2551,022
15564.22.104.0/2264.22.104.1 to 64.22.107.25464.22.107.2551,022
15664.22.108.0/2264.22.108.1 to 64.22.111.25464.22.111.2551,022
15764.22.112.0/2264.22.112.1 to 64.22.115.25464.22.115.2551,022
15864.22.116.0/2264.22.116.1 to 64.22.119.25464.22.119.2551,022
15964.22.120.0/2264.22.120.1 to 64.22.123.25464.22.123.2551,022
16064.22.124.0/2264.22.124.1 to 64.22.127.25464.22.127.2551,022
16164.22.128.0/2264.22.128.1 to 64.22.131.25464.22.131.2551,022
16264.22.132.0/2264.22.132.1 to 64.22.135.25464.22.135.2551,022
16364.22.136.0/2264.22.136.1 to 64.22.139.25464.22.139.2551,022
16464.22.140.0/2264.22.140.1 to 64.22.143.25464.22.143.2551,022
16564.22.144.0/2264.22.144.1 to 64.22.147.25464.22.147.2551,022
16664.22.148.0/2264.22.148.1 to 64.22.151.25464.22.151.2551,022
16764.22.152.0/2264.22.152.1 to 64.22.155.25464.22.155.2551,022
16864.22.156.0/2264.22.156.1 to 64.22.159.25464.22.159.2551,022
16964.22.160.0/2264.22.160.1 to 64.22.163.25464.22.163.2551,022
17064.22.164.0/2264.22.164.1 to 64.22.167.25464.22.167.2551,022
17164.22.168.0/2264.22.168.1 to 64.22.171.25464.22.171.2551,022
17264.22.172.0/2264.22.172.1 to 64.22.175.25464.22.175.2551,022
17364.22.176.0/2264.22.176.1 to 64.22.179.25464.22.179.2551,022
17464.22.180.0/2264.22.180.1 to 64.22.183.25464.22.183.2551,022
17564.22.184.0/2264.22.184.1 to 64.22.187.25464.22.187.2551,022
17664.22.188.0/2264.22.188.1 to 64.22.191.25464.22.191.2551,022
17764.22.192.0/2264.22.192.1 to 64.22.195.25464.22.195.2551,022
17864.22.196.0/2264.22.196.1 to 64.22.199.25464.22.199.2551,022
17964.22.200.0/2264.22.200.1 to 64.22.203.25464.22.203.2551,022
18064.22.204.0/2264.22.204.1 to 64.22.207.25464.22.207.2551,022
18164.22.208.0/2264.22.208.1 to 64.22.211.25464.22.211.2551,022
18264.22.212.0/2264.22.212.1 to 64.22.215.25464.22.215.2551,022
18364.22.216.0/2264.22.216.1 to 64.22.219.25464.22.219.2551,022
18464.22.220.0/2264.22.220.1 to 64.22.223.25464.22.223.2551,022
18564.22.224.0/2264.22.224.1 to 64.22.227.25464.22.227.2551,022
18664.22.228.0/2264.22.228.1 to 64.22.231.25464.22.231.2551,022
18764.22.232.0/2264.22.232.1 to 64.22.235.25464.22.235.2551,022
18864.22.236.0/2264.22.236.1 to 64.22.239.25464.22.239.2551,022
18964.22.240.0/2264.22.240.1 to 64.22.243.25464.22.243.2551,022
19064.22.244.0/2264.22.244.1 to 64.22.247.25464.22.247.2551,022
19164.22.248.0/2264.22.248.1 to 64.22.251.25464.22.251.2551,022
19264.22.252.0/2264.22.252.1 to 64.22.255.25464.22.255.2551,022
19364.23.0.0/2264.23.0.1 to 64.23.3.25464.23.3.2551,022
19464.23.4.0/2264.23.4.1 to 64.23.7.25464.23.7.2551,022
19564.23.8.0/2264.23.8.1 to 64.23.11.25464.23.11.2551,022
19664.23.12.0/2264.23.12.1 to 64.23.15.25464.23.15.2551,022
19764.23.16.0/2264.23.16.1 to 64.23.19.25464.23.19.2551,022
19864.23.20.0/2264.23.20.1 to 64.23.23.25464.23.23.2551,022
19964.23.24.0/2264.23.24.1 to 64.23.27.25464.23.27.2551,022
20064.23.28.0/2264.23.28.1 to 64.23.31.25464.23.31.2551,022
20164.23.32.0/2264.23.32.1 to 64.23.35.25464.23.35.2551,022
20264.23.36.0/2264.23.36.1 to 64.23.39.25464.23.39.2551,022
20364.23.40.0/2264.23.40.1 to 64.23.43.25464.23.43.2551,022
20464.23.44.0/2264.23.44.1 to 64.23.47.25464.23.47.2551,022
20564.23.48.0/2264.23.48.1 to 64.23.51.25464.23.51.2551,022
20664.23.52.0/2264.23.52.1 to 64.23.55.25464.23.55.2551,022
20764.23.56.0/2264.23.56.1 to 64.23.59.25464.23.59.2551,022
20864.23.60.0/2264.23.60.1 to 64.23.63.25464.23.63.2551,022
20964.23.64.0/2264.23.64.1 to 64.23.67.25464.23.67.2551,022
21064.23.68.0/2264.23.68.1 to 64.23.71.25464.23.71.2551,022
21164.23.72.0/2264.23.72.1 to 64.23.75.25464.23.75.2551,022
21264.23.76.0/2264.23.76.1 to 64.23.79.25464.23.79.2551,022
21364.23.80.0/2264.23.80.1 to 64.23.83.25464.23.83.2551,022
21464.23.84.0/2264.23.84.1 to 64.23.87.25464.23.87.2551,022
21564.23.88.0/2264.23.88.1 to 64.23.91.25464.23.91.2551,022
21664.23.92.0/2264.23.92.1 to 64.23.95.25464.23.95.2551,022
21764.23.96.0/2264.23.96.1 to 64.23.99.25464.23.99.2551,022
21864.23.100.0/2264.23.100.1 to 64.23.103.25464.23.103.2551,022
21964.23.104.0/2264.23.104.1 to 64.23.107.25464.23.107.2551,022
22064.23.108.0/2264.23.108.1 to 64.23.111.25464.23.111.2551,022
22164.23.112.0/2264.23.112.1 to 64.23.115.25464.23.115.2551,022
22264.23.116.0/2264.23.116.1 to 64.23.119.25464.23.119.2551,022
22364.23.120.0/2264.23.120.1 to 64.23.123.25464.23.123.2551,022
22464.23.124.0/2264.23.124.1 to 64.23.127.25464.23.127.2551,022
22564.23.128.0/2264.23.128.1 to 64.23.131.25464.23.131.2551,022
22664.23.132.0/2264.23.132.1 to 64.23.135.25464.23.135.2551,022
22764.23.136.0/2264.23.136.1 to 64.23.139.25464.23.139.2551,022
22864.23.140.0/2264.23.140.1 to 64.23.143.25464.23.143.2551,022
22964.23.144.0/2264.23.144.1 to 64.23.147.25464.23.147.2551,022
23064.23.148.0/2264.23.148.1 to 64.23.151.25464.23.151.2551,022
23164.23.152.0/2264.23.152.1 to 64.23.155.25464.23.155.2551,022
23264.23.156.0/2264.23.156.1 to 64.23.159.25464.23.159.2551,022
23364.23.160.0/2264.23.160.1 to 64.23.163.25464.23.163.2551,022
23464.23.164.0/2264.23.164.1 to 64.23.167.25464.23.167.2551,022
23564.23.168.0/2264.23.168.1 to 64.23.171.25464.23.171.2551,022
23664.23.172.0/2264.23.172.1 to 64.23.175.25464.23.175.2551,022
23764.23.176.0/2264.23.176.1 to 64.23.179.25464.23.179.2551,022
23864.23.180.0/2264.23.180.1 to 64.23.183.25464.23.183.2551,022
23964.23.184.0/2264.23.184.1 to 64.23.187.25464.23.187.2551,022
24064.23.188.0/2264.23.188.1 to 64.23.191.25464.23.191.2551,022
24164.23.192.0/2264.23.192.1 to 64.23.195.25464.23.195.2551,022
24264.23.196.0/2264.23.196.1 to 64.23.199.25464.23.199.2551,022
24364.23.200.0/2264.23.200.1 to 64.23.203.25464.23.203.2551,022
24464.23.204.0/2264.23.204.1 to 64.23.207.25464.23.207.2551,022
24564.23.208.0/2264.23.208.1 to 64.23.211.25464.23.211.2551,022
24664.23.212.0/2264.23.212.1 to 64.23.215.25464.23.215.2551,022
24764.23.216.0/2264.23.216.1 to 64.23.219.25464.23.219.2551,022
24864.23.220.0/2264.23.220.1 to 64.23.223.25464.23.223.2551,022
24964.23.224.0/2264.23.224.1 to 64.23.227.25464.23.227.2551,022
25064.23.228.0/2264.23.228.1 to 64.23.231.25464.23.231.2551,022
25164.23.232.0/2264.23.232.1 to 64.23.235.25464.23.235.2551,022
25264.23.236.0/2264.23.236.1 to 64.23.239.25464.23.239.2551,022
25364.23.240.0/2264.23.240.1 to 64.23.243.25464.23.243.2551,022
25464.23.244.0/2264.23.244.1 to 64.23.247.25464.23.247.2551,022
25564.23.248.0/2264.23.248.1 to 64.23.251.25464.23.251.2551,022
25664.23.252.0/2264.23.252.1 to 64.23.255.25464.23.255.2551,022

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.