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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.

Network92.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
92.0.0.0
Broadcast address
92.255.255.255
First usable
92.0.0.1
Last usable
92.255.255.254
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 5C000000 · Integer 1543503872 to 1560281087
Reverse DNS zone
92.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011100..00000000.00000000.0000000092.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01011100..00000000.00000000.0000000092.0.0.0
Broadcast01011100..11111111.11111111.1111111192.255.255.255
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)

92.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
192.0.0.0/1692.0.0.1 to 92.0.255.25492.0.255.25565,534
292.1.0.0/1692.1.0.1 to 92.1.255.25492.1.255.25565,534
392.2.0.0/1692.2.0.1 to 92.2.255.25492.2.255.25565,534
492.3.0.0/1692.3.0.1 to 92.3.255.25492.3.255.25565,534
592.4.0.0/1692.4.0.1 to 92.4.255.25492.4.255.25565,534
692.5.0.0/1692.5.0.1 to 92.5.255.25492.5.255.25565,534
792.6.0.0/1692.6.0.1 to 92.6.255.25492.6.255.25565,534
892.7.0.0/1692.7.0.1 to 92.7.255.25492.7.255.25565,534
992.8.0.0/1692.8.0.1 to 92.8.255.25492.8.255.25565,534
1092.9.0.0/1692.9.0.1 to 92.9.255.25492.9.255.25565,534
1192.10.0.0/1692.10.0.1 to 92.10.255.25492.10.255.25565,534
1292.11.0.0/1692.11.0.1 to 92.11.255.25492.11.255.25565,534
1392.12.0.0/1692.12.0.1 to 92.12.255.25492.12.255.25565,534
1492.13.0.0/1692.13.0.1 to 92.13.255.25492.13.255.25565,534
1592.14.0.0/1692.14.0.1 to 92.14.255.25492.14.255.25565,534
1692.15.0.0/1692.15.0.1 to 92.15.255.25492.15.255.25565,534
1792.16.0.0/1692.16.0.1 to 92.16.255.25492.16.255.25565,534
1892.17.0.0/1692.17.0.1 to 92.17.255.25492.17.255.25565,534
1992.18.0.0/1692.18.0.1 to 92.18.255.25492.18.255.25565,534
2092.19.0.0/1692.19.0.1 to 92.19.255.25492.19.255.25565,534
2192.20.0.0/1692.20.0.1 to 92.20.255.25492.20.255.25565,534
2292.21.0.0/1692.21.0.1 to 92.21.255.25492.21.255.25565,534
2392.22.0.0/1692.22.0.1 to 92.22.255.25492.22.255.25565,534
2492.23.0.0/1692.23.0.1 to 92.23.255.25492.23.255.25565,534
2592.24.0.0/1692.24.0.1 to 92.24.255.25492.24.255.25565,534
2692.25.0.0/1692.25.0.1 to 92.25.255.25492.25.255.25565,534
2792.26.0.0/1692.26.0.1 to 92.26.255.25492.26.255.25565,534
2892.27.0.0/1692.27.0.1 to 92.27.255.25492.27.255.25565,534
2992.28.0.0/1692.28.0.1 to 92.28.255.25492.28.255.25565,534
3092.29.0.0/1692.29.0.1 to 92.29.255.25492.29.255.25565,534
3192.30.0.0/1692.30.0.1 to 92.30.255.25492.30.255.25565,534
3292.31.0.0/1692.31.0.1 to 92.31.255.25492.31.255.25565,534
3392.32.0.0/1692.32.0.1 to 92.32.255.25492.32.255.25565,534
3492.33.0.0/1692.33.0.1 to 92.33.255.25492.33.255.25565,534
3592.34.0.0/1692.34.0.1 to 92.34.255.25492.34.255.25565,534
3692.35.0.0/1692.35.0.1 to 92.35.255.25492.35.255.25565,534
3792.36.0.0/1692.36.0.1 to 92.36.255.25492.36.255.25565,534
3892.37.0.0/1692.37.0.1 to 92.37.255.25492.37.255.25565,534
3992.38.0.0/1692.38.0.1 to 92.38.255.25492.38.255.25565,534
4092.39.0.0/1692.39.0.1 to 92.39.255.25492.39.255.25565,534
4192.40.0.0/1692.40.0.1 to 92.40.255.25492.40.255.25565,534
4292.41.0.0/1692.41.0.1 to 92.41.255.25492.41.255.25565,534
4392.42.0.0/1692.42.0.1 to 92.42.255.25492.42.255.25565,534
4492.43.0.0/1692.43.0.1 to 92.43.255.25492.43.255.25565,534
4592.44.0.0/1692.44.0.1 to 92.44.255.25492.44.255.25565,534
4692.45.0.0/1692.45.0.1 to 92.45.255.25492.45.255.25565,534
4792.46.0.0/1692.46.0.1 to 92.46.255.25492.46.255.25565,534
4892.47.0.0/1692.47.0.1 to 92.47.255.25492.47.255.25565,534
4992.48.0.0/1692.48.0.1 to 92.48.255.25492.48.255.25565,534
5092.49.0.0/1692.49.0.1 to 92.49.255.25492.49.255.25565,534
5192.50.0.0/1692.50.0.1 to 92.50.255.25492.50.255.25565,534
5292.51.0.0/1692.51.0.1 to 92.51.255.25492.51.255.25565,534
5392.52.0.0/1692.52.0.1 to 92.52.255.25492.52.255.25565,534
5492.53.0.0/1692.53.0.1 to 92.53.255.25492.53.255.25565,534
5592.54.0.0/1692.54.0.1 to 92.54.255.25492.54.255.25565,534
5692.55.0.0/1692.55.0.1 to 92.55.255.25492.55.255.25565,534
5792.56.0.0/1692.56.0.1 to 92.56.255.25492.56.255.25565,534
5892.57.0.0/1692.57.0.1 to 92.57.255.25492.57.255.25565,534
5992.58.0.0/1692.58.0.1 to 92.58.255.25492.58.255.25565,534
6092.59.0.0/1692.59.0.1 to 92.59.255.25492.59.255.25565,534
6192.60.0.0/1692.60.0.1 to 92.60.255.25492.60.255.25565,534
6292.61.0.0/1692.61.0.1 to 92.61.255.25492.61.255.25565,534
6392.62.0.0/1692.62.0.1 to 92.62.255.25492.62.255.25565,534
6492.63.0.0/1692.63.0.1 to 92.63.255.25492.63.255.25565,534
6592.64.0.0/1692.64.0.1 to 92.64.255.25492.64.255.25565,534
6692.65.0.0/1692.65.0.1 to 92.65.255.25492.65.255.25565,534
6792.66.0.0/1692.66.0.1 to 92.66.255.25492.66.255.25565,534
6892.67.0.0/1692.67.0.1 to 92.67.255.25492.67.255.25565,534
6992.68.0.0/1692.68.0.1 to 92.68.255.25492.68.255.25565,534
7092.69.0.0/1692.69.0.1 to 92.69.255.25492.69.255.25565,534
7192.70.0.0/1692.70.0.1 to 92.70.255.25492.70.255.25565,534
7292.71.0.0/1692.71.0.1 to 92.71.255.25492.71.255.25565,534
7392.72.0.0/1692.72.0.1 to 92.72.255.25492.72.255.25565,534
7492.73.0.0/1692.73.0.1 to 92.73.255.25492.73.255.25565,534
7592.74.0.0/1692.74.0.1 to 92.74.255.25492.74.255.25565,534
7692.75.0.0/1692.75.0.1 to 92.75.255.25492.75.255.25565,534
7792.76.0.0/1692.76.0.1 to 92.76.255.25492.76.255.25565,534
7892.77.0.0/1692.77.0.1 to 92.77.255.25492.77.255.25565,534
7992.78.0.0/1692.78.0.1 to 92.78.255.25492.78.255.25565,534
8092.79.0.0/1692.79.0.1 to 92.79.255.25492.79.255.25565,534
8192.80.0.0/1692.80.0.1 to 92.80.255.25492.80.255.25565,534
8292.81.0.0/1692.81.0.1 to 92.81.255.25492.81.255.25565,534
8392.82.0.0/1692.82.0.1 to 92.82.255.25492.82.255.25565,534
8492.83.0.0/1692.83.0.1 to 92.83.255.25492.83.255.25565,534
8592.84.0.0/1692.84.0.1 to 92.84.255.25492.84.255.25565,534
8692.85.0.0/1692.85.0.1 to 92.85.255.25492.85.255.25565,534
8792.86.0.0/1692.86.0.1 to 92.86.255.25492.86.255.25565,534
8892.87.0.0/1692.87.0.1 to 92.87.255.25492.87.255.25565,534
8992.88.0.0/1692.88.0.1 to 92.88.255.25492.88.255.25565,534
9092.89.0.0/1692.89.0.1 to 92.89.255.25492.89.255.25565,534
9192.90.0.0/1692.90.0.1 to 92.90.255.25492.90.255.25565,534
9292.91.0.0/1692.91.0.1 to 92.91.255.25492.91.255.25565,534
9392.92.0.0/1692.92.0.1 to 92.92.255.25492.92.255.25565,534
9492.93.0.0/1692.93.0.1 to 92.93.255.25492.93.255.25565,534
9592.94.0.0/1692.94.0.1 to 92.94.255.25492.94.255.25565,534
9692.95.0.0/1692.95.0.1 to 92.95.255.25492.95.255.25565,534
9792.96.0.0/1692.96.0.1 to 92.96.255.25492.96.255.25565,534
9892.97.0.0/1692.97.0.1 to 92.97.255.25492.97.255.25565,534
9992.98.0.0/1692.98.0.1 to 92.98.255.25492.98.255.25565,534
10092.99.0.0/1692.99.0.1 to 92.99.255.25492.99.255.25565,534
10192.100.0.0/1692.100.0.1 to 92.100.255.25492.100.255.25565,534
10292.101.0.0/1692.101.0.1 to 92.101.255.25492.101.255.25565,534
10392.102.0.0/1692.102.0.1 to 92.102.255.25492.102.255.25565,534
10492.103.0.0/1692.103.0.1 to 92.103.255.25492.103.255.25565,534
10592.104.0.0/1692.104.0.1 to 92.104.255.25492.104.255.25565,534
10692.105.0.0/1692.105.0.1 to 92.105.255.25492.105.255.25565,534
10792.106.0.0/1692.106.0.1 to 92.106.255.25492.106.255.25565,534
10892.107.0.0/1692.107.0.1 to 92.107.255.25492.107.255.25565,534
10992.108.0.0/1692.108.0.1 to 92.108.255.25492.108.255.25565,534
11092.109.0.0/1692.109.0.1 to 92.109.255.25492.109.255.25565,534
11192.110.0.0/1692.110.0.1 to 92.110.255.25492.110.255.25565,534
11292.111.0.0/1692.111.0.1 to 92.111.255.25492.111.255.25565,534
11392.112.0.0/1692.112.0.1 to 92.112.255.25492.112.255.25565,534
11492.113.0.0/1692.113.0.1 to 92.113.255.25492.113.255.25565,534
11592.114.0.0/1692.114.0.1 to 92.114.255.25492.114.255.25565,534
11692.115.0.0/1692.115.0.1 to 92.115.255.25492.115.255.25565,534
11792.116.0.0/1692.116.0.1 to 92.116.255.25492.116.255.25565,534
11892.117.0.0/1692.117.0.1 to 92.117.255.25492.117.255.25565,534
11992.118.0.0/1692.118.0.1 to 92.118.255.25492.118.255.25565,534
12092.119.0.0/1692.119.0.1 to 92.119.255.25492.119.255.25565,534
12192.120.0.0/1692.120.0.1 to 92.120.255.25492.120.255.25565,534
12292.121.0.0/1692.121.0.1 to 92.121.255.25492.121.255.25565,534
12392.122.0.0/1692.122.0.1 to 92.122.255.25492.122.255.25565,534
12492.123.0.0/1692.123.0.1 to 92.123.255.25492.123.255.25565,534
12592.124.0.0/1692.124.0.1 to 92.124.255.25492.124.255.25565,534
12692.125.0.0/1692.125.0.1 to 92.125.255.25492.125.255.25565,534
12792.126.0.0/1692.126.0.1 to 92.126.255.25492.126.255.25565,534
12892.127.0.0/1692.127.0.1 to 92.127.255.25492.127.255.25565,534
12992.128.0.0/1692.128.0.1 to 92.128.255.25492.128.255.25565,534
13092.129.0.0/1692.129.0.1 to 92.129.255.25492.129.255.25565,534
13192.130.0.0/1692.130.0.1 to 92.130.255.25492.130.255.25565,534
13292.131.0.0/1692.131.0.1 to 92.131.255.25492.131.255.25565,534
13392.132.0.0/1692.132.0.1 to 92.132.255.25492.132.255.25565,534
13492.133.0.0/1692.133.0.1 to 92.133.255.25492.133.255.25565,534
13592.134.0.0/1692.134.0.1 to 92.134.255.25492.134.255.25565,534
13692.135.0.0/1692.135.0.1 to 92.135.255.25492.135.255.25565,534
13792.136.0.0/1692.136.0.1 to 92.136.255.25492.136.255.25565,534
13892.137.0.0/1692.137.0.1 to 92.137.255.25492.137.255.25565,534
13992.138.0.0/1692.138.0.1 to 92.138.255.25492.138.255.25565,534
14092.139.0.0/1692.139.0.1 to 92.139.255.25492.139.255.25565,534
14192.140.0.0/1692.140.0.1 to 92.140.255.25492.140.255.25565,534
14292.141.0.0/1692.141.0.1 to 92.141.255.25492.141.255.25565,534
14392.142.0.0/1692.142.0.1 to 92.142.255.25492.142.255.25565,534
14492.143.0.0/1692.143.0.1 to 92.143.255.25492.143.255.25565,534
14592.144.0.0/1692.144.0.1 to 92.144.255.25492.144.255.25565,534
14692.145.0.0/1692.145.0.1 to 92.145.255.25492.145.255.25565,534
14792.146.0.0/1692.146.0.1 to 92.146.255.25492.146.255.25565,534
14892.147.0.0/1692.147.0.1 to 92.147.255.25492.147.255.25565,534
14992.148.0.0/1692.148.0.1 to 92.148.255.25492.148.255.25565,534
15092.149.0.0/1692.149.0.1 to 92.149.255.25492.149.255.25565,534
15192.150.0.0/1692.150.0.1 to 92.150.255.25492.150.255.25565,534
15292.151.0.0/1692.151.0.1 to 92.151.255.25492.151.255.25565,534
15392.152.0.0/1692.152.0.1 to 92.152.255.25492.152.255.25565,534
15492.153.0.0/1692.153.0.1 to 92.153.255.25492.153.255.25565,534
15592.154.0.0/1692.154.0.1 to 92.154.255.25492.154.255.25565,534
15692.155.0.0/1692.155.0.1 to 92.155.255.25492.155.255.25565,534
15792.156.0.0/1692.156.0.1 to 92.156.255.25492.156.255.25565,534
15892.157.0.0/1692.157.0.1 to 92.157.255.25492.157.255.25565,534
15992.158.0.0/1692.158.0.1 to 92.158.255.25492.158.255.25565,534
16092.159.0.0/1692.159.0.1 to 92.159.255.25492.159.255.25565,534
16192.160.0.0/1692.160.0.1 to 92.160.255.25492.160.255.25565,534
16292.161.0.0/1692.161.0.1 to 92.161.255.25492.161.255.25565,534
16392.162.0.0/1692.162.0.1 to 92.162.255.25492.162.255.25565,534
16492.163.0.0/1692.163.0.1 to 92.163.255.25492.163.255.25565,534
16592.164.0.0/1692.164.0.1 to 92.164.255.25492.164.255.25565,534
16692.165.0.0/1692.165.0.1 to 92.165.255.25492.165.255.25565,534
16792.166.0.0/1692.166.0.1 to 92.166.255.25492.166.255.25565,534
16892.167.0.0/1692.167.0.1 to 92.167.255.25492.167.255.25565,534
16992.168.0.0/1692.168.0.1 to 92.168.255.25492.168.255.25565,534
17092.169.0.0/1692.169.0.1 to 92.169.255.25492.169.255.25565,534
17192.170.0.0/1692.170.0.1 to 92.170.255.25492.170.255.25565,534
17292.171.0.0/1692.171.0.1 to 92.171.255.25492.171.255.25565,534
17392.172.0.0/1692.172.0.1 to 92.172.255.25492.172.255.25565,534
17492.173.0.0/1692.173.0.1 to 92.173.255.25492.173.255.25565,534
17592.174.0.0/1692.174.0.1 to 92.174.255.25492.174.255.25565,534
17692.175.0.0/1692.175.0.1 to 92.175.255.25492.175.255.25565,534
17792.176.0.0/1692.176.0.1 to 92.176.255.25492.176.255.25565,534
17892.177.0.0/1692.177.0.1 to 92.177.255.25492.177.255.25565,534
17992.178.0.0/1692.178.0.1 to 92.178.255.25492.178.255.25565,534
18092.179.0.0/1692.179.0.1 to 92.179.255.25492.179.255.25565,534
18192.180.0.0/1692.180.0.1 to 92.180.255.25492.180.255.25565,534
18292.181.0.0/1692.181.0.1 to 92.181.255.25492.181.255.25565,534
18392.182.0.0/1692.182.0.1 to 92.182.255.25492.182.255.25565,534
18492.183.0.0/1692.183.0.1 to 92.183.255.25492.183.255.25565,534
18592.184.0.0/1692.184.0.1 to 92.184.255.25492.184.255.25565,534
18692.185.0.0/1692.185.0.1 to 92.185.255.25492.185.255.25565,534
18792.186.0.0/1692.186.0.1 to 92.186.255.25492.186.255.25565,534
18892.187.0.0/1692.187.0.1 to 92.187.255.25492.187.255.25565,534
18992.188.0.0/1692.188.0.1 to 92.188.255.25492.188.255.25565,534
19092.189.0.0/1692.189.0.1 to 92.189.255.25492.189.255.25565,534
19192.190.0.0/1692.190.0.1 to 92.190.255.25492.190.255.25565,534
19292.191.0.0/1692.191.0.1 to 92.191.255.25492.191.255.25565,534
19392.192.0.0/1692.192.0.1 to 92.192.255.25492.192.255.25565,534
19492.193.0.0/1692.193.0.1 to 92.193.255.25492.193.255.25565,534
19592.194.0.0/1692.194.0.1 to 92.194.255.25492.194.255.25565,534
19692.195.0.0/1692.195.0.1 to 92.195.255.25492.195.255.25565,534
19792.196.0.0/1692.196.0.1 to 92.196.255.25492.196.255.25565,534
19892.197.0.0/1692.197.0.1 to 92.197.255.25492.197.255.25565,534
19992.198.0.0/1692.198.0.1 to 92.198.255.25492.198.255.25565,534
20092.199.0.0/1692.199.0.1 to 92.199.255.25492.199.255.25565,534
20192.200.0.0/1692.200.0.1 to 92.200.255.25492.200.255.25565,534
20292.201.0.0/1692.201.0.1 to 92.201.255.25492.201.255.25565,534
20392.202.0.0/1692.202.0.1 to 92.202.255.25492.202.255.25565,534
20492.203.0.0/1692.203.0.1 to 92.203.255.25492.203.255.25565,534
20592.204.0.0/1692.204.0.1 to 92.204.255.25492.204.255.25565,534
20692.205.0.0/1692.205.0.1 to 92.205.255.25492.205.255.25565,534
20792.206.0.0/1692.206.0.1 to 92.206.255.25492.206.255.25565,534
20892.207.0.0/1692.207.0.1 to 92.207.255.25492.207.255.25565,534
20992.208.0.0/1692.208.0.1 to 92.208.255.25492.208.255.25565,534
21092.209.0.0/1692.209.0.1 to 92.209.255.25492.209.255.25565,534
21192.210.0.0/1692.210.0.1 to 92.210.255.25492.210.255.25565,534
21292.211.0.0/1692.211.0.1 to 92.211.255.25492.211.255.25565,534
21392.212.0.0/1692.212.0.1 to 92.212.255.25492.212.255.25565,534
21492.213.0.0/1692.213.0.1 to 92.213.255.25492.213.255.25565,534
21592.214.0.0/1692.214.0.1 to 92.214.255.25492.214.255.25565,534
21692.215.0.0/1692.215.0.1 to 92.215.255.25492.215.255.25565,534
21792.216.0.0/1692.216.0.1 to 92.216.255.25492.216.255.25565,534
21892.217.0.0/1692.217.0.1 to 92.217.255.25492.217.255.25565,534
21992.218.0.0/1692.218.0.1 to 92.218.255.25492.218.255.25565,534
22092.219.0.0/1692.219.0.1 to 92.219.255.25492.219.255.25565,534
22192.220.0.0/1692.220.0.1 to 92.220.255.25492.220.255.25565,534
22292.221.0.0/1692.221.0.1 to 92.221.255.25492.221.255.25565,534
22392.222.0.0/1692.222.0.1 to 92.222.255.25492.222.255.25565,534
22492.223.0.0/1692.223.0.1 to 92.223.255.25492.223.255.25565,534
22592.224.0.0/1692.224.0.1 to 92.224.255.25492.224.255.25565,534
22692.225.0.0/1692.225.0.1 to 92.225.255.25492.225.255.25565,534
22792.226.0.0/1692.226.0.1 to 92.226.255.25492.226.255.25565,534
22892.227.0.0/1692.227.0.1 to 92.227.255.25492.227.255.25565,534
22992.228.0.0/1692.228.0.1 to 92.228.255.25492.228.255.25565,534
23092.229.0.0/1692.229.0.1 to 92.229.255.25492.229.255.25565,534
23192.230.0.0/1692.230.0.1 to 92.230.255.25492.230.255.25565,534
23292.231.0.0/1692.231.0.1 to 92.231.255.25492.231.255.25565,534
23392.232.0.0/1692.232.0.1 to 92.232.255.25492.232.255.25565,534
23492.233.0.0/1692.233.0.1 to 92.233.255.25492.233.255.25565,534
23592.234.0.0/1692.234.0.1 to 92.234.255.25492.234.255.25565,534
23692.235.0.0/1692.235.0.1 to 92.235.255.25492.235.255.25565,534
23792.236.0.0/1692.236.0.1 to 92.236.255.25492.236.255.25565,534
23892.237.0.0/1692.237.0.1 to 92.237.255.25492.237.255.25565,534
23992.238.0.0/1692.238.0.1 to 92.238.255.25492.238.255.25565,534
24092.239.0.0/1692.239.0.1 to 92.239.255.25492.239.255.25565,534
24192.240.0.0/1692.240.0.1 to 92.240.255.25492.240.255.25565,534
24292.241.0.0/1692.241.0.1 to 92.241.255.25492.241.255.25565,534
24392.242.0.0/1692.242.0.1 to 92.242.255.25492.242.255.25565,534
24492.243.0.0/1692.243.0.1 to 92.243.255.25492.243.255.25565,534
24592.244.0.0/1692.244.0.1 to 92.244.255.25492.244.255.25565,534
24692.245.0.0/1692.245.0.1 to 92.245.255.25492.245.255.25565,534
24792.246.0.0/1692.246.0.1 to 92.246.255.25492.246.255.25565,534
24892.247.0.0/1692.247.0.1 to 92.247.255.25492.247.255.25565,534
24992.248.0.0/1692.248.0.1 to 92.248.255.25492.248.255.25565,534
25092.249.0.0/1692.249.0.1 to 92.249.255.25492.249.255.25565,534
25192.250.0.0/1692.250.0.1 to 92.250.255.25492.250.255.25565,534
25292.251.0.0/1692.251.0.1 to 92.251.255.25492.251.255.25565,534
25392.252.0.0/1692.252.0.1 to 92.252.255.25492.252.255.25565,534
25492.253.0.0/1692.253.0.1 to 92.253.255.25492.253.255.25565,534
25592.254.0.0/1692.254.0.1 to 92.254.255.25492.254.255.25565,534
25692.255.0.0/1692.255.0.1 to 92.255.255.25492.255.255.25565,534

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.