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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.

Network22.64.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
22.64.0.0
Broadcast address
22.127.255.255
First usable
22.64.0.1
Last usable
22.127.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Public public
Old class
A (default /8)
As numbers
Hex 16400000 · Integer 373293056 to 377487359
Reverse DNS zones
64.22.in-addr.arpa
65.22.in-addr.arpa
66.22.in-addr.arpa
67.22.in-addr.arpa
68.22.in-addr.arpa
69.22.in-addr.arpa
70.22.in-addr.arpa
71.22.in-addr.arpa
72.22.in-addr.arpa
73.22.in-addr.arpa
74.22.in-addr.arpa
75.22.in-addr.arpa
76.22.in-addr.arpa
77.22.in-addr.arpa
78.22.in-addr.arpa
79.22.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00010110.01000000.00000000.0000000022.64.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00010110.01000000.00000000.0000000022.64.0.0
Broadcast00010110.01111111.11111111.1111111122.127.255.255
Split into smaller subnets/22
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

22.64.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
122.64.0.0/2222.64.0.1 to 22.64.3.25422.64.3.2551,022
222.64.4.0/2222.64.4.1 to 22.64.7.25422.64.7.2551,022
322.64.8.0/2222.64.8.1 to 22.64.11.25422.64.11.2551,022
422.64.12.0/2222.64.12.1 to 22.64.15.25422.64.15.2551,022
522.64.16.0/2222.64.16.1 to 22.64.19.25422.64.19.2551,022
622.64.20.0/2222.64.20.1 to 22.64.23.25422.64.23.2551,022
722.64.24.0/2222.64.24.1 to 22.64.27.25422.64.27.2551,022
822.64.28.0/2222.64.28.1 to 22.64.31.25422.64.31.2551,022
922.64.32.0/2222.64.32.1 to 22.64.35.25422.64.35.2551,022
1022.64.36.0/2222.64.36.1 to 22.64.39.25422.64.39.2551,022
1122.64.40.0/2222.64.40.1 to 22.64.43.25422.64.43.2551,022
1222.64.44.0/2222.64.44.1 to 22.64.47.25422.64.47.2551,022
1322.64.48.0/2222.64.48.1 to 22.64.51.25422.64.51.2551,022
1422.64.52.0/2222.64.52.1 to 22.64.55.25422.64.55.2551,022
1522.64.56.0/2222.64.56.1 to 22.64.59.25422.64.59.2551,022
1622.64.60.0/2222.64.60.1 to 22.64.63.25422.64.63.2551,022
1722.64.64.0/2222.64.64.1 to 22.64.67.25422.64.67.2551,022
1822.64.68.0/2222.64.68.1 to 22.64.71.25422.64.71.2551,022
1922.64.72.0/2222.64.72.1 to 22.64.75.25422.64.75.2551,022
2022.64.76.0/2222.64.76.1 to 22.64.79.25422.64.79.2551,022
2122.64.80.0/2222.64.80.1 to 22.64.83.25422.64.83.2551,022
2222.64.84.0/2222.64.84.1 to 22.64.87.25422.64.87.2551,022
2322.64.88.0/2222.64.88.1 to 22.64.91.25422.64.91.2551,022
2422.64.92.0/2222.64.92.1 to 22.64.95.25422.64.95.2551,022
2522.64.96.0/2222.64.96.1 to 22.64.99.25422.64.99.2551,022
2622.64.100.0/2222.64.100.1 to 22.64.103.25422.64.103.2551,022
2722.64.104.0/2222.64.104.1 to 22.64.107.25422.64.107.2551,022
2822.64.108.0/2222.64.108.1 to 22.64.111.25422.64.111.2551,022
2922.64.112.0/2222.64.112.1 to 22.64.115.25422.64.115.2551,022
3022.64.116.0/2222.64.116.1 to 22.64.119.25422.64.119.2551,022
3122.64.120.0/2222.64.120.1 to 22.64.123.25422.64.123.2551,022
3222.64.124.0/2222.64.124.1 to 22.64.127.25422.64.127.2551,022
3322.64.128.0/2222.64.128.1 to 22.64.131.25422.64.131.2551,022
3422.64.132.0/2222.64.132.1 to 22.64.135.25422.64.135.2551,022
3522.64.136.0/2222.64.136.1 to 22.64.139.25422.64.139.2551,022
3622.64.140.0/2222.64.140.1 to 22.64.143.25422.64.143.2551,022
3722.64.144.0/2222.64.144.1 to 22.64.147.25422.64.147.2551,022
3822.64.148.0/2222.64.148.1 to 22.64.151.25422.64.151.2551,022
3922.64.152.0/2222.64.152.1 to 22.64.155.25422.64.155.2551,022
4022.64.156.0/2222.64.156.1 to 22.64.159.25422.64.159.2551,022
4122.64.160.0/2222.64.160.1 to 22.64.163.25422.64.163.2551,022
4222.64.164.0/2222.64.164.1 to 22.64.167.25422.64.167.2551,022
4322.64.168.0/2222.64.168.1 to 22.64.171.25422.64.171.2551,022
4422.64.172.0/2222.64.172.1 to 22.64.175.25422.64.175.2551,022
4522.64.176.0/2222.64.176.1 to 22.64.179.25422.64.179.2551,022
4622.64.180.0/2222.64.180.1 to 22.64.183.25422.64.183.2551,022
4722.64.184.0/2222.64.184.1 to 22.64.187.25422.64.187.2551,022
4822.64.188.0/2222.64.188.1 to 22.64.191.25422.64.191.2551,022
4922.64.192.0/2222.64.192.1 to 22.64.195.25422.64.195.2551,022
5022.64.196.0/2222.64.196.1 to 22.64.199.25422.64.199.2551,022
5122.64.200.0/2222.64.200.1 to 22.64.203.25422.64.203.2551,022
5222.64.204.0/2222.64.204.1 to 22.64.207.25422.64.207.2551,022
5322.64.208.0/2222.64.208.1 to 22.64.211.25422.64.211.2551,022
5422.64.212.0/2222.64.212.1 to 22.64.215.25422.64.215.2551,022
5522.64.216.0/2222.64.216.1 to 22.64.219.25422.64.219.2551,022
5622.64.220.0/2222.64.220.1 to 22.64.223.25422.64.223.2551,022
5722.64.224.0/2222.64.224.1 to 22.64.227.25422.64.227.2551,022
5822.64.228.0/2222.64.228.1 to 22.64.231.25422.64.231.2551,022
5922.64.232.0/2222.64.232.1 to 22.64.235.25422.64.235.2551,022
6022.64.236.0/2222.64.236.1 to 22.64.239.25422.64.239.2551,022
6122.64.240.0/2222.64.240.1 to 22.64.243.25422.64.243.2551,022
6222.64.244.0/2222.64.244.1 to 22.64.247.25422.64.247.2551,022
6322.64.248.0/2222.64.248.1 to 22.64.251.25422.64.251.2551,022
6422.64.252.0/2222.64.252.1 to 22.64.255.25422.64.255.2551,022
6522.65.0.0/2222.65.0.1 to 22.65.3.25422.65.3.2551,022
6622.65.4.0/2222.65.4.1 to 22.65.7.25422.65.7.2551,022
6722.65.8.0/2222.65.8.1 to 22.65.11.25422.65.11.2551,022
6822.65.12.0/2222.65.12.1 to 22.65.15.25422.65.15.2551,022
6922.65.16.0/2222.65.16.1 to 22.65.19.25422.65.19.2551,022
7022.65.20.0/2222.65.20.1 to 22.65.23.25422.65.23.2551,022
7122.65.24.0/2222.65.24.1 to 22.65.27.25422.65.27.2551,022
7222.65.28.0/2222.65.28.1 to 22.65.31.25422.65.31.2551,022
7322.65.32.0/2222.65.32.1 to 22.65.35.25422.65.35.2551,022
7422.65.36.0/2222.65.36.1 to 22.65.39.25422.65.39.2551,022
7522.65.40.0/2222.65.40.1 to 22.65.43.25422.65.43.2551,022
7622.65.44.0/2222.65.44.1 to 22.65.47.25422.65.47.2551,022
7722.65.48.0/2222.65.48.1 to 22.65.51.25422.65.51.2551,022
7822.65.52.0/2222.65.52.1 to 22.65.55.25422.65.55.2551,022
7922.65.56.0/2222.65.56.1 to 22.65.59.25422.65.59.2551,022
8022.65.60.0/2222.65.60.1 to 22.65.63.25422.65.63.2551,022
8122.65.64.0/2222.65.64.1 to 22.65.67.25422.65.67.2551,022
8222.65.68.0/2222.65.68.1 to 22.65.71.25422.65.71.2551,022
8322.65.72.0/2222.65.72.1 to 22.65.75.25422.65.75.2551,022
8422.65.76.0/2222.65.76.1 to 22.65.79.25422.65.79.2551,022
8522.65.80.0/2222.65.80.1 to 22.65.83.25422.65.83.2551,022
8622.65.84.0/2222.65.84.1 to 22.65.87.25422.65.87.2551,022
8722.65.88.0/2222.65.88.1 to 22.65.91.25422.65.91.2551,022
8822.65.92.0/2222.65.92.1 to 22.65.95.25422.65.95.2551,022
8922.65.96.0/2222.65.96.1 to 22.65.99.25422.65.99.2551,022
9022.65.100.0/2222.65.100.1 to 22.65.103.25422.65.103.2551,022
9122.65.104.0/2222.65.104.1 to 22.65.107.25422.65.107.2551,022
9222.65.108.0/2222.65.108.1 to 22.65.111.25422.65.111.2551,022
9322.65.112.0/2222.65.112.1 to 22.65.115.25422.65.115.2551,022
9422.65.116.0/2222.65.116.1 to 22.65.119.25422.65.119.2551,022
9522.65.120.0/2222.65.120.1 to 22.65.123.25422.65.123.2551,022
9622.65.124.0/2222.65.124.1 to 22.65.127.25422.65.127.2551,022
9722.65.128.0/2222.65.128.1 to 22.65.131.25422.65.131.2551,022
9822.65.132.0/2222.65.132.1 to 22.65.135.25422.65.135.2551,022
9922.65.136.0/2222.65.136.1 to 22.65.139.25422.65.139.2551,022
10022.65.140.0/2222.65.140.1 to 22.65.143.25422.65.143.2551,022
10122.65.144.0/2222.65.144.1 to 22.65.147.25422.65.147.2551,022
10222.65.148.0/2222.65.148.1 to 22.65.151.25422.65.151.2551,022
10322.65.152.0/2222.65.152.1 to 22.65.155.25422.65.155.2551,022
10422.65.156.0/2222.65.156.1 to 22.65.159.25422.65.159.2551,022
10522.65.160.0/2222.65.160.1 to 22.65.163.25422.65.163.2551,022
10622.65.164.0/2222.65.164.1 to 22.65.167.25422.65.167.2551,022
10722.65.168.0/2222.65.168.1 to 22.65.171.25422.65.171.2551,022
10822.65.172.0/2222.65.172.1 to 22.65.175.25422.65.175.2551,022
10922.65.176.0/2222.65.176.1 to 22.65.179.25422.65.179.2551,022
11022.65.180.0/2222.65.180.1 to 22.65.183.25422.65.183.2551,022
11122.65.184.0/2222.65.184.1 to 22.65.187.25422.65.187.2551,022
11222.65.188.0/2222.65.188.1 to 22.65.191.25422.65.191.2551,022
11322.65.192.0/2222.65.192.1 to 22.65.195.25422.65.195.2551,022
11422.65.196.0/2222.65.196.1 to 22.65.199.25422.65.199.2551,022
11522.65.200.0/2222.65.200.1 to 22.65.203.25422.65.203.2551,022
11622.65.204.0/2222.65.204.1 to 22.65.207.25422.65.207.2551,022
11722.65.208.0/2222.65.208.1 to 22.65.211.25422.65.211.2551,022
11822.65.212.0/2222.65.212.1 to 22.65.215.25422.65.215.2551,022
11922.65.216.0/2222.65.216.1 to 22.65.219.25422.65.219.2551,022
12022.65.220.0/2222.65.220.1 to 22.65.223.25422.65.223.2551,022
12122.65.224.0/2222.65.224.1 to 22.65.227.25422.65.227.2551,022
12222.65.228.0/2222.65.228.1 to 22.65.231.25422.65.231.2551,022
12322.65.232.0/2222.65.232.1 to 22.65.235.25422.65.235.2551,022
12422.65.236.0/2222.65.236.1 to 22.65.239.25422.65.239.2551,022
12522.65.240.0/2222.65.240.1 to 22.65.243.25422.65.243.2551,022
12622.65.244.0/2222.65.244.1 to 22.65.247.25422.65.247.2551,022
12722.65.248.0/2222.65.248.1 to 22.65.251.25422.65.251.2551,022
12822.65.252.0/2222.65.252.1 to 22.65.255.25422.65.255.2551,022
12922.66.0.0/2222.66.0.1 to 22.66.3.25422.66.3.2551,022
13022.66.4.0/2222.66.4.1 to 22.66.7.25422.66.7.2551,022
13122.66.8.0/2222.66.8.1 to 22.66.11.25422.66.11.2551,022
13222.66.12.0/2222.66.12.1 to 22.66.15.25422.66.15.2551,022
13322.66.16.0/2222.66.16.1 to 22.66.19.25422.66.19.2551,022
13422.66.20.0/2222.66.20.1 to 22.66.23.25422.66.23.2551,022
13522.66.24.0/2222.66.24.1 to 22.66.27.25422.66.27.2551,022
13622.66.28.0/2222.66.28.1 to 22.66.31.25422.66.31.2551,022
13722.66.32.0/2222.66.32.1 to 22.66.35.25422.66.35.2551,022
13822.66.36.0/2222.66.36.1 to 22.66.39.25422.66.39.2551,022
13922.66.40.0/2222.66.40.1 to 22.66.43.25422.66.43.2551,022
14022.66.44.0/2222.66.44.1 to 22.66.47.25422.66.47.2551,022
14122.66.48.0/2222.66.48.1 to 22.66.51.25422.66.51.2551,022
14222.66.52.0/2222.66.52.1 to 22.66.55.25422.66.55.2551,022
14322.66.56.0/2222.66.56.1 to 22.66.59.25422.66.59.2551,022
14422.66.60.0/2222.66.60.1 to 22.66.63.25422.66.63.2551,022
14522.66.64.0/2222.66.64.1 to 22.66.67.25422.66.67.2551,022
14622.66.68.0/2222.66.68.1 to 22.66.71.25422.66.71.2551,022
14722.66.72.0/2222.66.72.1 to 22.66.75.25422.66.75.2551,022
14822.66.76.0/2222.66.76.1 to 22.66.79.25422.66.79.2551,022
14922.66.80.0/2222.66.80.1 to 22.66.83.25422.66.83.2551,022
15022.66.84.0/2222.66.84.1 to 22.66.87.25422.66.87.2551,022
15122.66.88.0/2222.66.88.1 to 22.66.91.25422.66.91.2551,022
15222.66.92.0/2222.66.92.1 to 22.66.95.25422.66.95.2551,022
15322.66.96.0/2222.66.96.1 to 22.66.99.25422.66.99.2551,022
15422.66.100.0/2222.66.100.1 to 22.66.103.25422.66.103.2551,022
15522.66.104.0/2222.66.104.1 to 22.66.107.25422.66.107.2551,022
15622.66.108.0/2222.66.108.1 to 22.66.111.25422.66.111.2551,022
15722.66.112.0/2222.66.112.1 to 22.66.115.25422.66.115.2551,022
15822.66.116.0/2222.66.116.1 to 22.66.119.25422.66.119.2551,022
15922.66.120.0/2222.66.120.1 to 22.66.123.25422.66.123.2551,022
16022.66.124.0/2222.66.124.1 to 22.66.127.25422.66.127.2551,022
16122.66.128.0/2222.66.128.1 to 22.66.131.25422.66.131.2551,022
16222.66.132.0/2222.66.132.1 to 22.66.135.25422.66.135.2551,022
16322.66.136.0/2222.66.136.1 to 22.66.139.25422.66.139.2551,022
16422.66.140.0/2222.66.140.1 to 22.66.143.25422.66.143.2551,022
16522.66.144.0/2222.66.144.1 to 22.66.147.25422.66.147.2551,022
16622.66.148.0/2222.66.148.1 to 22.66.151.25422.66.151.2551,022
16722.66.152.0/2222.66.152.1 to 22.66.155.25422.66.155.2551,022
16822.66.156.0/2222.66.156.1 to 22.66.159.25422.66.159.2551,022
16922.66.160.0/2222.66.160.1 to 22.66.163.25422.66.163.2551,022
17022.66.164.0/2222.66.164.1 to 22.66.167.25422.66.167.2551,022
17122.66.168.0/2222.66.168.1 to 22.66.171.25422.66.171.2551,022
17222.66.172.0/2222.66.172.1 to 22.66.175.25422.66.175.2551,022
17322.66.176.0/2222.66.176.1 to 22.66.179.25422.66.179.2551,022
17422.66.180.0/2222.66.180.1 to 22.66.183.25422.66.183.2551,022
17522.66.184.0/2222.66.184.1 to 22.66.187.25422.66.187.2551,022
17622.66.188.0/2222.66.188.1 to 22.66.191.25422.66.191.2551,022
17722.66.192.0/2222.66.192.1 to 22.66.195.25422.66.195.2551,022
17822.66.196.0/2222.66.196.1 to 22.66.199.25422.66.199.2551,022
17922.66.200.0/2222.66.200.1 to 22.66.203.25422.66.203.2551,022
18022.66.204.0/2222.66.204.1 to 22.66.207.25422.66.207.2551,022
18122.66.208.0/2222.66.208.1 to 22.66.211.25422.66.211.2551,022
18222.66.212.0/2222.66.212.1 to 22.66.215.25422.66.215.2551,022
18322.66.216.0/2222.66.216.1 to 22.66.219.25422.66.219.2551,022
18422.66.220.0/2222.66.220.1 to 22.66.223.25422.66.223.2551,022
18522.66.224.0/2222.66.224.1 to 22.66.227.25422.66.227.2551,022
18622.66.228.0/2222.66.228.1 to 22.66.231.25422.66.231.2551,022
18722.66.232.0/2222.66.232.1 to 22.66.235.25422.66.235.2551,022
18822.66.236.0/2222.66.236.1 to 22.66.239.25422.66.239.2551,022
18922.66.240.0/2222.66.240.1 to 22.66.243.25422.66.243.2551,022
19022.66.244.0/2222.66.244.1 to 22.66.247.25422.66.247.2551,022
19122.66.248.0/2222.66.248.1 to 22.66.251.25422.66.251.2551,022
19222.66.252.0/2222.66.252.1 to 22.66.255.25422.66.255.2551,022
19322.67.0.0/2222.67.0.1 to 22.67.3.25422.67.3.2551,022
19422.67.4.0/2222.67.4.1 to 22.67.7.25422.67.7.2551,022
19522.67.8.0/2222.67.8.1 to 22.67.11.25422.67.11.2551,022
19622.67.12.0/2222.67.12.1 to 22.67.15.25422.67.15.2551,022
19722.67.16.0/2222.67.16.1 to 22.67.19.25422.67.19.2551,022
19822.67.20.0/2222.67.20.1 to 22.67.23.25422.67.23.2551,022
19922.67.24.0/2222.67.24.1 to 22.67.27.25422.67.27.2551,022
20022.67.28.0/2222.67.28.1 to 22.67.31.25422.67.31.2551,022
20122.67.32.0/2222.67.32.1 to 22.67.35.25422.67.35.2551,022
20222.67.36.0/2222.67.36.1 to 22.67.39.25422.67.39.2551,022
20322.67.40.0/2222.67.40.1 to 22.67.43.25422.67.43.2551,022
20422.67.44.0/2222.67.44.1 to 22.67.47.25422.67.47.2551,022
20522.67.48.0/2222.67.48.1 to 22.67.51.25422.67.51.2551,022
20622.67.52.0/2222.67.52.1 to 22.67.55.25422.67.55.2551,022
20722.67.56.0/2222.67.56.1 to 22.67.59.25422.67.59.2551,022
20822.67.60.0/2222.67.60.1 to 22.67.63.25422.67.63.2551,022
20922.67.64.0/2222.67.64.1 to 22.67.67.25422.67.67.2551,022
21022.67.68.0/2222.67.68.1 to 22.67.71.25422.67.71.2551,022
21122.67.72.0/2222.67.72.1 to 22.67.75.25422.67.75.2551,022
21222.67.76.0/2222.67.76.1 to 22.67.79.25422.67.79.2551,022
21322.67.80.0/2222.67.80.1 to 22.67.83.25422.67.83.2551,022
21422.67.84.0/2222.67.84.1 to 22.67.87.25422.67.87.2551,022
21522.67.88.0/2222.67.88.1 to 22.67.91.25422.67.91.2551,022
21622.67.92.0/2222.67.92.1 to 22.67.95.25422.67.95.2551,022
21722.67.96.0/2222.67.96.1 to 22.67.99.25422.67.99.2551,022
21822.67.100.0/2222.67.100.1 to 22.67.103.25422.67.103.2551,022
21922.67.104.0/2222.67.104.1 to 22.67.107.25422.67.107.2551,022
22022.67.108.0/2222.67.108.1 to 22.67.111.25422.67.111.2551,022
22122.67.112.0/2222.67.112.1 to 22.67.115.25422.67.115.2551,022
22222.67.116.0/2222.67.116.1 to 22.67.119.25422.67.119.2551,022
22322.67.120.0/2222.67.120.1 to 22.67.123.25422.67.123.2551,022
22422.67.124.0/2222.67.124.1 to 22.67.127.25422.67.127.2551,022
22522.67.128.0/2222.67.128.1 to 22.67.131.25422.67.131.2551,022
22622.67.132.0/2222.67.132.1 to 22.67.135.25422.67.135.2551,022
22722.67.136.0/2222.67.136.1 to 22.67.139.25422.67.139.2551,022
22822.67.140.0/2222.67.140.1 to 22.67.143.25422.67.143.2551,022
22922.67.144.0/2222.67.144.1 to 22.67.147.25422.67.147.2551,022
23022.67.148.0/2222.67.148.1 to 22.67.151.25422.67.151.2551,022
23122.67.152.0/2222.67.152.1 to 22.67.155.25422.67.155.2551,022
23222.67.156.0/2222.67.156.1 to 22.67.159.25422.67.159.2551,022
23322.67.160.0/2222.67.160.1 to 22.67.163.25422.67.163.2551,022
23422.67.164.0/2222.67.164.1 to 22.67.167.25422.67.167.2551,022
23522.67.168.0/2222.67.168.1 to 22.67.171.25422.67.171.2551,022
23622.67.172.0/2222.67.172.1 to 22.67.175.25422.67.175.2551,022
23722.67.176.0/2222.67.176.1 to 22.67.179.25422.67.179.2551,022
23822.67.180.0/2222.67.180.1 to 22.67.183.25422.67.183.2551,022
23922.67.184.0/2222.67.184.1 to 22.67.187.25422.67.187.2551,022
24022.67.188.0/2222.67.188.1 to 22.67.191.25422.67.191.2551,022
24122.67.192.0/2222.67.192.1 to 22.67.195.25422.67.195.2551,022
24222.67.196.0/2222.67.196.1 to 22.67.199.25422.67.199.2551,022
24322.67.200.0/2222.67.200.1 to 22.67.203.25422.67.203.2551,022
24422.67.204.0/2222.67.204.1 to 22.67.207.25422.67.207.2551,022
24522.67.208.0/2222.67.208.1 to 22.67.211.25422.67.211.2551,022
24622.67.212.0/2222.67.212.1 to 22.67.215.25422.67.215.2551,022
24722.67.216.0/2222.67.216.1 to 22.67.219.25422.67.219.2551,022
24822.67.220.0/2222.67.220.1 to 22.67.223.25422.67.223.2551,022
24922.67.224.0/2222.67.224.1 to 22.67.227.25422.67.227.2551,022
25022.67.228.0/2222.67.228.1 to 22.67.231.25422.67.231.2551,022
25122.67.232.0/2222.67.232.1 to 22.67.235.25422.67.235.2551,022
25222.67.236.0/2222.67.236.1 to 22.67.239.25422.67.239.2551,022
25322.67.240.0/2222.67.240.1 to 22.67.243.25422.67.243.2551,022
25422.67.244.0/2222.67.244.1 to 22.67.247.25422.67.247.2551,022
25522.67.248.0/2222.67.248.1 to 22.67.251.25422.67.251.2551,022
25622.67.252.0/2222.67.252.1 to 22.67.255.25422.67.255.2551,022

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.