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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.

Network22.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
22.0.0.0
Broadcast address
22.255.255.255
First usable
22.0.0.1
Last usable
22.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 16000000 · Integer 369098752 to 385875967
Reverse DNS zone
22.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00010110..00000000.00000000.0000000022.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network00010110..00000000.00000000.0000000022.0.0.0
Broadcast00010110..11111111.11111111.1111111122.255.255.255
Split into smaller subnets/16
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

22.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
122.0.0.0/1622.0.0.1 to 22.0.255.25422.0.255.25565,534
222.1.0.0/1622.1.0.1 to 22.1.255.25422.1.255.25565,534
322.2.0.0/1622.2.0.1 to 22.2.255.25422.2.255.25565,534
422.3.0.0/1622.3.0.1 to 22.3.255.25422.3.255.25565,534
522.4.0.0/1622.4.0.1 to 22.4.255.25422.4.255.25565,534
622.5.0.0/1622.5.0.1 to 22.5.255.25422.5.255.25565,534
722.6.0.0/1622.6.0.1 to 22.6.255.25422.6.255.25565,534
822.7.0.0/1622.7.0.1 to 22.7.255.25422.7.255.25565,534
922.8.0.0/1622.8.0.1 to 22.8.255.25422.8.255.25565,534
1022.9.0.0/1622.9.0.1 to 22.9.255.25422.9.255.25565,534
1122.10.0.0/1622.10.0.1 to 22.10.255.25422.10.255.25565,534
1222.11.0.0/1622.11.0.1 to 22.11.255.25422.11.255.25565,534
1322.12.0.0/1622.12.0.1 to 22.12.255.25422.12.255.25565,534
1422.13.0.0/1622.13.0.1 to 22.13.255.25422.13.255.25565,534
1522.14.0.0/1622.14.0.1 to 22.14.255.25422.14.255.25565,534
1622.15.0.0/1622.15.0.1 to 22.15.255.25422.15.255.25565,534
1722.16.0.0/1622.16.0.1 to 22.16.255.25422.16.255.25565,534
1822.17.0.0/1622.17.0.1 to 22.17.255.25422.17.255.25565,534
1922.18.0.0/1622.18.0.1 to 22.18.255.25422.18.255.25565,534
2022.19.0.0/1622.19.0.1 to 22.19.255.25422.19.255.25565,534
2122.20.0.0/1622.20.0.1 to 22.20.255.25422.20.255.25565,534
2222.21.0.0/1622.21.0.1 to 22.21.255.25422.21.255.25565,534
2322.22.0.0/1622.22.0.1 to 22.22.255.25422.22.255.25565,534
2422.23.0.0/1622.23.0.1 to 22.23.255.25422.23.255.25565,534
2522.24.0.0/1622.24.0.1 to 22.24.255.25422.24.255.25565,534
2622.25.0.0/1622.25.0.1 to 22.25.255.25422.25.255.25565,534
2722.26.0.0/1622.26.0.1 to 22.26.255.25422.26.255.25565,534
2822.27.0.0/1622.27.0.1 to 22.27.255.25422.27.255.25565,534
2922.28.0.0/1622.28.0.1 to 22.28.255.25422.28.255.25565,534
3022.29.0.0/1622.29.0.1 to 22.29.255.25422.29.255.25565,534
3122.30.0.0/1622.30.0.1 to 22.30.255.25422.30.255.25565,534
3222.31.0.0/1622.31.0.1 to 22.31.255.25422.31.255.25565,534
3322.32.0.0/1622.32.0.1 to 22.32.255.25422.32.255.25565,534
3422.33.0.0/1622.33.0.1 to 22.33.255.25422.33.255.25565,534
3522.34.0.0/1622.34.0.1 to 22.34.255.25422.34.255.25565,534
3622.35.0.0/1622.35.0.1 to 22.35.255.25422.35.255.25565,534
3722.36.0.0/1622.36.0.1 to 22.36.255.25422.36.255.25565,534
3822.37.0.0/1622.37.0.1 to 22.37.255.25422.37.255.25565,534
3922.38.0.0/1622.38.0.1 to 22.38.255.25422.38.255.25565,534
4022.39.0.0/1622.39.0.1 to 22.39.255.25422.39.255.25565,534
4122.40.0.0/1622.40.0.1 to 22.40.255.25422.40.255.25565,534
4222.41.0.0/1622.41.0.1 to 22.41.255.25422.41.255.25565,534
4322.42.0.0/1622.42.0.1 to 22.42.255.25422.42.255.25565,534
4422.43.0.0/1622.43.0.1 to 22.43.255.25422.43.255.25565,534
4522.44.0.0/1622.44.0.1 to 22.44.255.25422.44.255.25565,534
4622.45.0.0/1622.45.0.1 to 22.45.255.25422.45.255.25565,534
4722.46.0.0/1622.46.0.1 to 22.46.255.25422.46.255.25565,534
4822.47.0.0/1622.47.0.1 to 22.47.255.25422.47.255.25565,534
4922.48.0.0/1622.48.0.1 to 22.48.255.25422.48.255.25565,534
5022.49.0.0/1622.49.0.1 to 22.49.255.25422.49.255.25565,534
5122.50.0.0/1622.50.0.1 to 22.50.255.25422.50.255.25565,534
5222.51.0.0/1622.51.0.1 to 22.51.255.25422.51.255.25565,534
5322.52.0.0/1622.52.0.1 to 22.52.255.25422.52.255.25565,534
5422.53.0.0/1622.53.0.1 to 22.53.255.25422.53.255.25565,534
5522.54.0.0/1622.54.0.1 to 22.54.255.25422.54.255.25565,534
5622.55.0.0/1622.55.0.1 to 22.55.255.25422.55.255.25565,534
5722.56.0.0/1622.56.0.1 to 22.56.255.25422.56.255.25565,534
5822.57.0.0/1622.57.0.1 to 22.57.255.25422.57.255.25565,534
5922.58.0.0/1622.58.0.1 to 22.58.255.25422.58.255.25565,534
6022.59.0.0/1622.59.0.1 to 22.59.255.25422.59.255.25565,534
6122.60.0.0/1622.60.0.1 to 22.60.255.25422.60.255.25565,534
6222.61.0.0/1622.61.0.1 to 22.61.255.25422.61.255.25565,534
6322.62.0.0/1622.62.0.1 to 22.62.255.25422.62.255.25565,534
6422.63.0.0/1622.63.0.1 to 22.63.255.25422.63.255.25565,534
6522.64.0.0/1622.64.0.1 to 22.64.255.25422.64.255.25565,534
6622.65.0.0/1622.65.0.1 to 22.65.255.25422.65.255.25565,534
6722.66.0.0/1622.66.0.1 to 22.66.255.25422.66.255.25565,534
6822.67.0.0/1622.67.0.1 to 22.67.255.25422.67.255.25565,534
6922.68.0.0/1622.68.0.1 to 22.68.255.25422.68.255.25565,534
7022.69.0.0/1622.69.0.1 to 22.69.255.25422.69.255.25565,534
7122.70.0.0/1622.70.0.1 to 22.70.255.25422.70.255.25565,534
7222.71.0.0/1622.71.0.1 to 22.71.255.25422.71.255.25565,534
7322.72.0.0/1622.72.0.1 to 22.72.255.25422.72.255.25565,534
7422.73.0.0/1622.73.0.1 to 22.73.255.25422.73.255.25565,534
7522.74.0.0/1622.74.0.1 to 22.74.255.25422.74.255.25565,534
7622.75.0.0/1622.75.0.1 to 22.75.255.25422.75.255.25565,534
7722.76.0.0/1622.76.0.1 to 22.76.255.25422.76.255.25565,534
7822.77.0.0/1622.77.0.1 to 22.77.255.25422.77.255.25565,534
7922.78.0.0/1622.78.0.1 to 22.78.255.25422.78.255.25565,534
8022.79.0.0/1622.79.0.1 to 22.79.255.25422.79.255.25565,534
8122.80.0.0/1622.80.0.1 to 22.80.255.25422.80.255.25565,534
8222.81.0.0/1622.81.0.1 to 22.81.255.25422.81.255.25565,534
8322.82.0.0/1622.82.0.1 to 22.82.255.25422.82.255.25565,534
8422.83.0.0/1622.83.0.1 to 22.83.255.25422.83.255.25565,534
8522.84.0.0/1622.84.0.1 to 22.84.255.25422.84.255.25565,534
8622.85.0.0/1622.85.0.1 to 22.85.255.25422.85.255.25565,534
8722.86.0.0/1622.86.0.1 to 22.86.255.25422.86.255.25565,534
8822.87.0.0/1622.87.0.1 to 22.87.255.25422.87.255.25565,534
8922.88.0.0/1622.88.0.1 to 22.88.255.25422.88.255.25565,534
9022.89.0.0/1622.89.0.1 to 22.89.255.25422.89.255.25565,534
9122.90.0.0/1622.90.0.1 to 22.90.255.25422.90.255.25565,534
9222.91.0.0/1622.91.0.1 to 22.91.255.25422.91.255.25565,534
9322.92.0.0/1622.92.0.1 to 22.92.255.25422.92.255.25565,534
9422.93.0.0/1622.93.0.1 to 22.93.255.25422.93.255.25565,534
9522.94.0.0/1622.94.0.1 to 22.94.255.25422.94.255.25565,534
9622.95.0.0/1622.95.0.1 to 22.95.255.25422.95.255.25565,534
9722.96.0.0/1622.96.0.1 to 22.96.255.25422.96.255.25565,534
9822.97.0.0/1622.97.0.1 to 22.97.255.25422.97.255.25565,534
9922.98.0.0/1622.98.0.1 to 22.98.255.25422.98.255.25565,534
10022.99.0.0/1622.99.0.1 to 22.99.255.25422.99.255.25565,534
10122.100.0.0/1622.100.0.1 to 22.100.255.25422.100.255.25565,534
10222.101.0.0/1622.101.0.1 to 22.101.255.25422.101.255.25565,534
10322.102.0.0/1622.102.0.1 to 22.102.255.25422.102.255.25565,534
10422.103.0.0/1622.103.0.1 to 22.103.255.25422.103.255.25565,534
10522.104.0.0/1622.104.0.1 to 22.104.255.25422.104.255.25565,534
10622.105.0.0/1622.105.0.1 to 22.105.255.25422.105.255.25565,534
10722.106.0.0/1622.106.0.1 to 22.106.255.25422.106.255.25565,534
10822.107.0.0/1622.107.0.1 to 22.107.255.25422.107.255.25565,534
10922.108.0.0/1622.108.0.1 to 22.108.255.25422.108.255.25565,534
11022.109.0.0/1622.109.0.1 to 22.109.255.25422.109.255.25565,534
11122.110.0.0/1622.110.0.1 to 22.110.255.25422.110.255.25565,534
11222.111.0.0/1622.111.0.1 to 22.111.255.25422.111.255.25565,534
11322.112.0.0/1622.112.0.1 to 22.112.255.25422.112.255.25565,534
11422.113.0.0/1622.113.0.1 to 22.113.255.25422.113.255.25565,534
11522.114.0.0/1622.114.0.1 to 22.114.255.25422.114.255.25565,534
11622.115.0.0/1622.115.0.1 to 22.115.255.25422.115.255.25565,534
11722.116.0.0/1622.116.0.1 to 22.116.255.25422.116.255.25565,534
11822.117.0.0/1622.117.0.1 to 22.117.255.25422.117.255.25565,534
11922.118.0.0/1622.118.0.1 to 22.118.255.25422.118.255.25565,534
12022.119.0.0/1622.119.0.1 to 22.119.255.25422.119.255.25565,534
12122.120.0.0/1622.120.0.1 to 22.120.255.25422.120.255.25565,534
12222.121.0.0/1622.121.0.1 to 22.121.255.25422.121.255.25565,534
12322.122.0.0/1622.122.0.1 to 22.122.255.25422.122.255.25565,534
12422.123.0.0/1622.123.0.1 to 22.123.255.25422.123.255.25565,534
12522.124.0.0/1622.124.0.1 to 22.124.255.25422.124.255.25565,534
12622.125.0.0/1622.125.0.1 to 22.125.255.25422.125.255.25565,534
12722.126.0.0/1622.126.0.1 to 22.126.255.25422.126.255.25565,534
12822.127.0.0/1622.127.0.1 to 22.127.255.25422.127.255.25565,534
12922.128.0.0/1622.128.0.1 to 22.128.255.25422.128.255.25565,534
13022.129.0.0/1622.129.0.1 to 22.129.255.25422.129.255.25565,534
13122.130.0.0/1622.130.0.1 to 22.130.255.25422.130.255.25565,534
13222.131.0.0/1622.131.0.1 to 22.131.255.25422.131.255.25565,534
13322.132.0.0/1622.132.0.1 to 22.132.255.25422.132.255.25565,534
13422.133.0.0/1622.133.0.1 to 22.133.255.25422.133.255.25565,534
13522.134.0.0/1622.134.0.1 to 22.134.255.25422.134.255.25565,534
13622.135.0.0/1622.135.0.1 to 22.135.255.25422.135.255.25565,534
13722.136.0.0/1622.136.0.1 to 22.136.255.25422.136.255.25565,534
13822.137.0.0/1622.137.0.1 to 22.137.255.25422.137.255.25565,534
13922.138.0.0/1622.138.0.1 to 22.138.255.25422.138.255.25565,534
14022.139.0.0/1622.139.0.1 to 22.139.255.25422.139.255.25565,534
14122.140.0.0/1622.140.0.1 to 22.140.255.25422.140.255.25565,534
14222.141.0.0/1622.141.0.1 to 22.141.255.25422.141.255.25565,534
14322.142.0.0/1622.142.0.1 to 22.142.255.25422.142.255.25565,534
14422.143.0.0/1622.143.0.1 to 22.143.255.25422.143.255.25565,534
14522.144.0.0/1622.144.0.1 to 22.144.255.25422.144.255.25565,534
14622.145.0.0/1622.145.0.1 to 22.145.255.25422.145.255.25565,534
14722.146.0.0/1622.146.0.1 to 22.146.255.25422.146.255.25565,534
14822.147.0.0/1622.147.0.1 to 22.147.255.25422.147.255.25565,534
14922.148.0.0/1622.148.0.1 to 22.148.255.25422.148.255.25565,534
15022.149.0.0/1622.149.0.1 to 22.149.255.25422.149.255.25565,534
15122.150.0.0/1622.150.0.1 to 22.150.255.25422.150.255.25565,534
15222.151.0.0/1622.151.0.1 to 22.151.255.25422.151.255.25565,534
15322.152.0.0/1622.152.0.1 to 22.152.255.25422.152.255.25565,534
15422.153.0.0/1622.153.0.1 to 22.153.255.25422.153.255.25565,534
15522.154.0.0/1622.154.0.1 to 22.154.255.25422.154.255.25565,534
15622.155.0.0/1622.155.0.1 to 22.155.255.25422.155.255.25565,534
15722.156.0.0/1622.156.0.1 to 22.156.255.25422.156.255.25565,534
15822.157.0.0/1622.157.0.1 to 22.157.255.25422.157.255.25565,534
15922.158.0.0/1622.158.0.1 to 22.158.255.25422.158.255.25565,534
16022.159.0.0/1622.159.0.1 to 22.159.255.25422.159.255.25565,534
16122.160.0.0/1622.160.0.1 to 22.160.255.25422.160.255.25565,534
16222.161.0.0/1622.161.0.1 to 22.161.255.25422.161.255.25565,534
16322.162.0.0/1622.162.0.1 to 22.162.255.25422.162.255.25565,534
16422.163.0.0/1622.163.0.1 to 22.163.255.25422.163.255.25565,534
16522.164.0.0/1622.164.0.1 to 22.164.255.25422.164.255.25565,534
16622.165.0.0/1622.165.0.1 to 22.165.255.25422.165.255.25565,534
16722.166.0.0/1622.166.0.1 to 22.166.255.25422.166.255.25565,534
16822.167.0.0/1622.167.0.1 to 22.167.255.25422.167.255.25565,534
16922.168.0.0/1622.168.0.1 to 22.168.255.25422.168.255.25565,534
17022.169.0.0/1622.169.0.1 to 22.169.255.25422.169.255.25565,534
17122.170.0.0/1622.170.0.1 to 22.170.255.25422.170.255.25565,534
17222.171.0.0/1622.171.0.1 to 22.171.255.25422.171.255.25565,534
17322.172.0.0/1622.172.0.1 to 22.172.255.25422.172.255.25565,534
17422.173.0.0/1622.173.0.1 to 22.173.255.25422.173.255.25565,534
17522.174.0.0/1622.174.0.1 to 22.174.255.25422.174.255.25565,534
17622.175.0.0/1622.175.0.1 to 22.175.255.25422.175.255.25565,534
17722.176.0.0/1622.176.0.1 to 22.176.255.25422.176.255.25565,534
17822.177.0.0/1622.177.0.1 to 22.177.255.25422.177.255.25565,534
17922.178.0.0/1622.178.0.1 to 22.178.255.25422.178.255.25565,534
18022.179.0.0/1622.179.0.1 to 22.179.255.25422.179.255.25565,534
18122.180.0.0/1622.180.0.1 to 22.180.255.25422.180.255.25565,534
18222.181.0.0/1622.181.0.1 to 22.181.255.25422.181.255.25565,534
18322.182.0.0/1622.182.0.1 to 22.182.255.25422.182.255.25565,534
18422.183.0.0/1622.183.0.1 to 22.183.255.25422.183.255.25565,534
18522.184.0.0/1622.184.0.1 to 22.184.255.25422.184.255.25565,534
18622.185.0.0/1622.185.0.1 to 22.185.255.25422.185.255.25565,534
18722.186.0.0/1622.186.0.1 to 22.186.255.25422.186.255.25565,534
18822.187.0.0/1622.187.0.1 to 22.187.255.25422.187.255.25565,534
18922.188.0.0/1622.188.0.1 to 22.188.255.25422.188.255.25565,534
19022.189.0.0/1622.189.0.1 to 22.189.255.25422.189.255.25565,534
19122.190.0.0/1622.190.0.1 to 22.190.255.25422.190.255.25565,534
19222.191.0.0/1622.191.0.1 to 22.191.255.25422.191.255.25565,534
19322.192.0.0/1622.192.0.1 to 22.192.255.25422.192.255.25565,534
19422.193.0.0/1622.193.0.1 to 22.193.255.25422.193.255.25565,534
19522.194.0.0/1622.194.0.1 to 22.194.255.25422.194.255.25565,534
19622.195.0.0/1622.195.0.1 to 22.195.255.25422.195.255.25565,534
19722.196.0.0/1622.196.0.1 to 22.196.255.25422.196.255.25565,534
19822.197.0.0/1622.197.0.1 to 22.197.255.25422.197.255.25565,534
19922.198.0.0/1622.198.0.1 to 22.198.255.25422.198.255.25565,534
20022.199.0.0/1622.199.0.1 to 22.199.255.25422.199.255.25565,534
20122.200.0.0/1622.200.0.1 to 22.200.255.25422.200.255.25565,534
20222.201.0.0/1622.201.0.1 to 22.201.255.25422.201.255.25565,534
20322.202.0.0/1622.202.0.1 to 22.202.255.25422.202.255.25565,534
20422.203.0.0/1622.203.0.1 to 22.203.255.25422.203.255.25565,534
20522.204.0.0/1622.204.0.1 to 22.204.255.25422.204.255.25565,534
20622.205.0.0/1622.205.0.1 to 22.205.255.25422.205.255.25565,534
20722.206.0.0/1622.206.0.1 to 22.206.255.25422.206.255.25565,534
20822.207.0.0/1622.207.0.1 to 22.207.255.25422.207.255.25565,534
20922.208.0.0/1622.208.0.1 to 22.208.255.25422.208.255.25565,534
21022.209.0.0/1622.209.0.1 to 22.209.255.25422.209.255.25565,534
21122.210.0.0/1622.210.0.1 to 22.210.255.25422.210.255.25565,534
21222.211.0.0/1622.211.0.1 to 22.211.255.25422.211.255.25565,534
21322.212.0.0/1622.212.0.1 to 22.212.255.25422.212.255.25565,534
21422.213.0.0/1622.213.0.1 to 22.213.255.25422.213.255.25565,534
21522.214.0.0/1622.214.0.1 to 22.214.255.25422.214.255.25565,534
21622.215.0.0/1622.215.0.1 to 22.215.255.25422.215.255.25565,534
21722.216.0.0/1622.216.0.1 to 22.216.255.25422.216.255.25565,534
21822.217.0.0/1622.217.0.1 to 22.217.255.25422.217.255.25565,534
21922.218.0.0/1622.218.0.1 to 22.218.255.25422.218.255.25565,534
22022.219.0.0/1622.219.0.1 to 22.219.255.25422.219.255.25565,534
22122.220.0.0/1622.220.0.1 to 22.220.255.25422.220.255.25565,534
22222.221.0.0/1622.221.0.1 to 22.221.255.25422.221.255.25565,534
22322.222.0.0/1622.222.0.1 to 22.222.255.25422.222.255.25565,534
22422.223.0.0/1622.223.0.1 to 22.223.255.25422.223.255.25565,534
22522.224.0.0/1622.224.0.1 to 22.224.255.25422.224.255.25565,534
22622.225.0.0/1622.225.0.1 to 22.225.255.25422.225.255.25565,534
22722.226.0.0/1622.226.0.1 to 22.226.255.25422.226.255.25565,534
22822.227.0.0/1622.227.0.1 to 22.227.255.25422.227.255.25565,534
22922.228.0.0/1622.228.0.1 to 22.228.255.25422.228.255.25565,534
23022.229.0.0/1622.229.0.1 to 22.229.255.25422.229.255.25565,534
23122.230.0.0/1622.230.0.1 to 22.230.255.25422.230.255.25565,534
23222.231.0.0/1622.231.0.1 to 22.231.255.25422.231.255.25565,534
23322.232.0.0/1622.232.0.1 to 22.232.255.25422.232.255.25565,534
23422.233.0.0/1622.233.0.1 to 22.233.255.25422.233.255.25565,534
23522.234.0.0/1622.234.0.1 to 22.234.255.25422.234.255.25565,534
23622.235.0.0/1622.235.0.1 to 22.235.255.25422.235.255.25565,534
23722.236.0.0/1622.236.0.1 to 22.236.255.25422.236.255.25565,534
23822.237.0.0/1622.237.0.1 to 22.237.255.25422.237.255.25565,534
23922.238.0.0/1622.238.0.1 to 22.238.255.25422.238.255.25565,534
24022.239.0.0/1622.239.0.1 to 22.239.255.25422.239.255.25565,534
24122.240.0.0/1622.240.0.1 to 22.240.255.25422.240.255.25565,534
24222.241.0.0/1622.241.0.1 to 22.241.255.25422.241.255.25565,534
24322.242.0.0/1622.242.0.1 to 22.242.255.25422.242.255.25565,534
24422.243.0.0/1622.243.0.1 to 22.243.255.25422.243.255.25565,534
24522.244.0.0/1622.244.0.1 to 22.244.255.25422.244.255.25565,534
24622.245.0.0/1622.245.0.1 to 22.245.255.25422.245.255.25565,534
24722.246.0.0/1622.246.0.1 to 22.246.255.25422.246.255.25565,534
24822.247.0.0/1622.247.0.1 to 22.247.255.25422.247.255.25565,534
24922.248.0.0/1622.248.0.1 to 22.248.255.25422.248.255.25565,534
25022.249.0.0/1622.249.0.1 to 22.249.255.25422.249.255.25565,534
25122.250.0.0/1622.250.0.1 to 22.250.255.25422.250.255.25565,534
25222.251.0.0/1622.251.0.1 to 22.251.255.25422.251.255.25565,534
25322.252.0.0/1622.252.0.1 to 22.252.255.25422.252.255.25565,534
25422.253.0.0/1622.253.0.1 to 22.253.255.25422.253.255.25565,534
25522.254.0.0/1622.254.0.1 to 22.254.255.25422.254.255.25565,534
25622.255.0.0/1622.255.0.1 to 22.255.255.25422.255.255.25565,534

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.