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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.

Network92.0.0.0/6
Usable hosts67,108,862
Subnet mask252.0.0.0
Addresses67,108,864
Network address
92.0.0.0
Broadcast address
95.255.255.255
First usable
92.0.0.1
Last usable
95.255.255.254
Usable hosts
67,108,862 (67,108,864 less the network and broadcast addresses)
Subnet mask
252.0.0.0
Wildcard mask
3.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/6
Type
Public public
Old class
A (default /8)
As numbers
Hex 5C000000 · Integer 1543503872 to 1610612735
Reverse DNS zones
92.in-addr.arpa
93.in-addr.arpa
94.in-addr.arpa
95.in-addr.arpa
/6 is not on a 8-bit boundary, so it takes 4 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011100.00000000.00000000.0000000092.0.0.0
Subnet mask11111100.00000000.00000000.00000000252.0.0.0
Network01011100.00000000.00000000.0000000092.0.0.0
Broadcast01011111.11111111.11111111.1111111195.255.255.255
Split into smaller subnets/15
/7 (2)/8 (4)/9 (8)/10 (16)/11 (32)/12 (64)/13 (128)/14 (256)/15 (512)/16 (1,024)/17 (2,048)/18 (4,096)

92.0.0.0/6 makes 512 subnets of /15; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
192.0.0.0/1592.0.0.1 to 92.1.255.25492.1.255.255131,070
292.2.0.0/1592.2.0.1 to 92.3.255.25492.3.255.255131,070
392.4.0.0/1592.4.0.1 to 92.5.255.25492.5.255.255131,070
492.6.0.0/1592.6.0.1 to 92.7.255.25492.7.255.255131,070
592.8.0.0/1592.8.0.1 to 92.9.255.25492.9.255.255131,070
692.10.0.0/1592.10.0.1 to 92.11.255.25492.11.255.255131,070
792.12.0.0/1592.12.0.1 to 92.13.255.25492.13.255.255131,070
892.14.0.0/1592.14.0.1 to 92.15.255.25492.15.255.255131,070
992.16.0.0/1592.16.0.1 to 92.17.255.25492.17.255.255131,070
1092.18.0.0/1592.18.0.1 to 92.19.255.25492.19.255.255131,070
1192.20.0.0/1592.20.0.1 to 92.21.255.25492.21.255.255131,070
1292.22.0.0/1592.22.0.1 to 92.23.255.25492.23.255.255131,070
1392.24.0.0/1592.24.0.1 to 92.25.255.25492.25.255.255131,070
1492.26.0.0/1592.26.0.1 to 92.27.255.25492.27.255.255131,070
1592.28.0.0/1592.28.0.1 to 92.29.255.25492.29.255.255131,070
1692.30.0.0/1592.30.0.1 to 92.31.255.25492.31.255.255131,070
1792.32.0.0/1592.32.0.1 to 92.33.255.25492.33.255.255131,070
1892.34.0.0/1592.34.0.1 to 92.35.255.25492.35.255.255131,070
1992.36.0.0/1592.36.0.1 to 92.37.255.25492.37.255.255131,070
2092.38.0.0/1592.38.0.1 to 92.39.255.25492.39.255.255131,070
2192.40.0.0/1592.40.0.1 to 92.41.255.25492.41.255.255131,070
2292.42.0.0/1592.42.0.1 to 92.43.255.25492.43.255.255131,070
2392.44.0.0/1592.44.0.1 to 92.45.255.25492.45.255.255131,070
2492.46.0.0/1592.46.0.1 to 92.47.255.25492.47.255.255131,070
2592.48.0.0/1592.48.0.1 to 92.49.255.25492.49.255.255131,070
2692.50.0.0/1592.50.0.1 to 92.51.255.25492.51.255.255131,070
2792.52.0.0/1592.52.0.1 to 92.53.255.25492.53.255.255131,070
2892.54.0.0/1592.54.0.1 to 92.55.255.25492.55.255.255131,070
2992.56.0.0/1592.56.0.1 to 92.57.255.25492.57.255.255131,070
3092.58.0.0/1592.58.0.1 to 92.59.255.25492.59.255.255131,070
3192.60.0.0/1592.60.0.1 to 92.61.255.25492.61.255.255131,070
3292.62.0.0/1592.62.0.1 to 92.63.255.25492.63.255.255131,070
3392.64.0.0/1592.64.0.1 to 92.65.255.25492.65.255.255131,070
3492.66.0.0/1592.66.0.1 to 92.67.255.25492.67.255.255131,070
3592.68.0.0/1592.68.0.1 to 92.69.255.25492.69.255.255131,070
3692.70.0.0/1592.70.0.1 to 92.71.255.25492.71.255.255131,070
3792.72.0.0/1592.72.0.1 to 92.73.255.25492.73.255.255131,070
3892.74.0.0/1592.74.0.1 to 92.75.255.25492.75.255.255131,070
3992.76.0.0/1592.76.0.1 to 92.77.255.25492.77.255.255131,070
4092.78.0.0/1592.78.0.1 to 92.79.255.25492.79.255.255131,070
4192.80.0.0/1592.80.0.1 to 92.81.255.25492.81.255.255131,070
4292.82.0.0/1592.82.0.1 to 92.83.255.25492.83.255.255131,070
4392.84.0.0/1592.84.0.1 to 92.85.255.25492.85.255.255131,070
4492.86.0.0/1592.86.0.1 to 92.87.255.25492.87.255.255131,070
4592.88.0.0/1592.88.0.1 to 92.89.255.25492.89.255.255131,070
4692.90.0.0/1592.90.0.1 to 92.91.255.25492.91.255.255131,070
4792.92.0.0/1592.92.0.1 to 92.93.255.25492.93.255.255131,070
4892.94.0.0/1592.94.0.1 to 92.95.255.25492.95.255.255131,070
4992.96.0.0/1592.96.0.1 to 92.97.255.25492.97.255.255131,070
5092.98.0.0/1592.98.0.1 to 92.99.255.25492.99.255.255131,070
5192.100.0.0/1592.100.0.1 to 92.101.255.25492.101.255.255131,070
5292.102.0.0/1592.102.0.1 to 92.103.255.25492.103.255.255131,070
5392.104.0.0/1592.104.0.1 to 92.105.255.25492.105.255.255131,070
5492.106.0.0/1592.106.0.1 to 92.107.255.25492.107.255.255131,070
5592.108.0.0/1592.108.0.1 to 92.109.255.25492.109.255.255131,070
5692.110.0.0/1592.110.0.1 to 92.111.255.25492.111.255.255131,070
5792.112.0.0/1592.112.0.1 to 92.113.255.25492.113.255.255131,070
5892.114.0.0/1592.114.0.1 to 92.115.255.25492.115.255.255131,070
5992.116.0.0/1592.116.0.1 to 92.117.255.25492.117.255.255131,070
6092.118.0.0/1592.118.0.1 to 92.119.255.25492.119.255.255131,070
6192.120.0.0/1592.120.0.1 to 92.121.255.25492.121.255.255131,070
6292.122.0.0/1592.122.0.1 to 92.123.255.25492.123.255.255131,070
6392.124.0.0/1592.124.0.1 to 92.125.255.25492.125.255.255131,070
6492.126.0.0/1592.126.0.1 to 92.127.255.25492.127.255.255131,070
6592.128.0.0/1592.128.0.1 to 92.129.255.25492.129.255.255131,070
6692.130.0.0/1592.130.0.1 to 92.131.255.25492.131.255.255131,070
6792.132.0.0/1592.132.0.1 to 92.133.255.25492.133.255.255131,070
6892.134.0.0/1592.134.0.1 to 92.135.255.25492.135.255.255131,070
6992.136.0.0/1592.136.0.1 to 92.137.255.25492.137.255.255131,070
7092.138.0.0/1592.138.0.1 to 92.139.255.25492.139.255.255131,070
7192.140.0.0/1592.140.0.1 to 92.141.255.25492.141.255.255131,070
7292.142.0.0/1592.142.0.1 to 92.143.255.25492.143.255.255131,070
7392.144.0.0/1592.144.0.1 to 92.145.255.25492.145.255.255131,070
7492.146.0.0/1592.146.0.1 to 92.147.255.25492.147.255.255131,070
7592.148.0.0/1592.148.0.1 to 92.149.255.25492.149.255.255131,070
7692.150.0.0/1592.150.0.1 to 92.151.255.25492.151.255.255131,070
7792.152.0.0/1592.152.0.1 to 92.153.255.25492.153.255.255131,070
7892.154.0.0/1592.154.0.1 to 92.155.255.25492.155.255.255131,070
7992.156.0.0/1592.156.0.1 to 92.157.255.25492.157.255.255131,070
8092.158.0.0/1592.158.0.1 to 92.159.255.25492.159.255.255131,070
8192.160.0.0/1592.160.0.1 to 92.161.255.25492.161.255.255131,070
8292.162.0.0/1592.162.0.1 to 92.163.255.25492.163.255.255131,070
8392.164.0.0/1592.164.0.1 to 92.165.255.25492.165.255.255131,070
8492.166.0.0/1592.166.0.1 to 92.167.255.25492.167.255.255131,070
8592.168.0.0/1592.168.0.1 to 92.169.255.25492.169.255.255131,070
8692.170.0.0/1592.170.0.1 to 92.171.255.25492.171.255.255131,070
8792.172.0.0/1592.172.0.1 to 92.173.255.25492.173.255.255131,070
8892.174.0.0/1592.174.0.1 to 92.175.255.25492.175.255.255131,070
8992.176.0.0/1592.176.0.1 to 92.177.255.25492.177.255.255131,070
9092.178.0.0/1592.178.0.1 to 92.179.255.25492.179.255.255131,070
9192.180.0.0/1592.180.0.1 to 92.181.255.25492.181.255.255131,070
9292.182.0.0/1592.182.0.1 to 92.183.255.25492.183.255.255131,070
9392.184.0.0/1592.184.0.1 to 92.185.255.25492.185.255.255131,070
9492.186.0.0/1592.186.0.1 to 92.187.255.25492.187.255.255131,070
9592.188.0.0/1592.188.0.1 to 92.189.255.25492.189.255.255131,070
9692.190.0.0/1592.190.0.1 to 92.191.255.25492.191.255.255131,070
9792.192.0.0/1592.192.0.1 to 92.193.255.25492.193.255.255131,070
9892.194.0.0/1592.194.0.1 to 92.195.255.25492.195.255.255131,070
9992.196.0.0/1592.196.0.1 to 92.197.255.25492.197.255.255131,070
10092.198.0.0/1592.198.0.1 to 92.199.255.25492.199.255.255131,070
10192.200.0.0/1592.200.0.1 to 92.201.255.25492.201.255.255131,070
10292.202.0.0/1592.202.0.1 to 92.203.255.25492.203.255.255131,070
10392.204.0.0/1592.204.0.1 to 92.205.255.25492.205.255.255131,070
10492.206.0.0/1592.206.0.1 to 92.207.255.25492.207.255.255131,070
10592.208.0.0/1592.208.0.1 to 92.209.255.25492.209.255.255131,070
10692.210.0.0/1592.210.0.1 to 92.211.255.25492.211.255.255131,070
10792.212.0.0/1592.212.0.1 to 92.213.255.25492.213.255.255131,070
10892.214.0.0/1592.214.0.1 to 92.215.255.25492.215.255.255131,070
10992.216.0.0/1592.216.0.1 to 92.217.255.25492.217.255.255131,070
11092.218.0.0/1592.218.0.1 to 92.219.255.25492.219.255.255131,070
11192.220.0.0/1592.220.0.1 to 92.221.255.25492.221.255.255131,070
11292.222.0.0/1592.222.0.1 to 92.223.255.25492.223.255.255131,070
11392.224.0.0/1592.224.0.1 to 92.225.255.25492.225.255.255131,070
11492.226.0.0/1592.226.0.1 to 92.227.255.25492.227.255.255131,070
11592.228.0.0/1592.228.0.1 to 92.229.255.25492.229.255.255131,070
11692.230.0.0/1592.230.0.1 to 92.231.255.25492.231.255.255131,070
11792.232.0.0/1592.232.0.1 to 92.233.255.25492.233.255.255131,070
11892.234.0.0/1592.234.0.1 to 92.235.255.25492.235.255.255131,070
11992.236.0.0/1592.236.0.1 to 92.237.255.25492.237.255.255131,070
12092.238.0.0/1592.238.0.1 to 92.239.255.25492.239.255.255131,070
12192.240.0.0/1592.240.0.1 to 92.241.255.25492.241.255.255131,070
12292.242.0.0/1592.242.0.1 to 92.243.255.25492.243.255.255131,070
12392.244.0.0/1592.244.0.1 to 92.245.255.25492.245.255.255131,070
12492.246.0.0/1592.246.0.1 to 92.247.255.25492.247.255.255131,070
12592.248.0.0/1592.248.0.1 to 92.249.255.25492.249.255.255131,070
12692.250.0.0/1592.250.0.1 to 92.251.255.25492.251.255.255131,070
12792.252.0.0/1592.252.0.1 to 92.253.255.25492.253.255.255131,070
12892.254.0.0/1592.254.0.1 to 92.255.255.25492.255.255.255131,070
12993.0.0.0/1593.0.0.1 to 93.1.255.25493.1.255.255131,070
13093.2.0.0/1593.2.0.1 to 93.3.255.25493.3.255.255131,070
13193.4.0.0/1593.4.0.1 to 93.5.255.25493.5.255.255131,070
13293.6.0.0/1593.6.0.1 to 93.7.255.25493.7.255.255131,070
13393.8.0.0/1593.8.0.1 to 93.9.255.25493.9.255.255131,070
13493.10.0.0/1593.10.0.1 to 93.11.255.25493.11.255.255131,070
13593.12.0.0/1593.12.0.1 to 93.13.255.25493.13.255.255131,070
13693.14.0.0/1593.14.0.1 to 93.15.255.25493.15.255.255131,070
13793.16.0.0/1593.16.0.1 to 93.17.255.25493.17.255.255131,070
13893.18.0.0/1593.18.0.1 to 93.19.255.25493.19.255.255131,070
13993.20.0.0/1593.20.0.1 to 93.21.255.25493.21.255.255131,070
14093.22.0.0/1593.22.0.1 to 93.23.255.25493.23.255.255131,070
14193.24.0.0/1593.24.0.1 to 93.25.255.25493.25.255.255131,070
14293.26.0.0/1593.26.0.1 to 93.27.255.25493.27.255.255131,070
14393.28.0.0/1593.28.0.1 to 93.29.255.25493.29.255.255131,070
14493.30.0.0/1593.30.0.1 to 93.31.255.25493.31.255.255131,070
14593.32.0.0/1593.32.0.1 to 93.33.255.25493.33.255.255131,070
14693.34.0.0/1593.34.0.1 to 93.35.255.25493.35.255.255131,070
14793.36.0.0/1593.36.0.1 to 93.37.255.25493.37.255.255131,070
14893.38.0.0/1593.38.0.1 to 93.39.255.25493.39.255.255131,070
14993.40.0.0/1593.40.0.1 to 93.41.255.25493.41.255.255131,070
15093.42.0.0/1593.42.0.1 to 93.43.255.25493.43.255.255131,070
15193.44.0.0/1593.44.0.1 to 93.45.255.25493.45.255.255131,070
15293.46.0.0/1593.46.0.1 to 93.47.255.25493.47.255.255131,070
15393.48.0.0/1593.48.0.1 to 93.49.255.25493.49.255.255131,070
15493.50.0.0/1593.50.0.1 to 93.51.255.25493.51.255.255131,070
15593.52.0.0/1593.52.0.1 to 93.53.255.25493.53.255.255131,070
15693.54.0.0/1593.54.0.1 to 93.55.255.25493.55.255.255131,070
15793.56.0.0/1593.56.0.1 to 93.57.255.25493.57.255.255131,070
15893.58.0.0/1593.58.0.1 to 93.59.255.25493.59.255.255131,070
15993.60.0.0/1593.60.0.1 to 93.61.255.25493.61.255.255131,070
16093.62.0.0/1593.62.0.1 to 93.63.255.25493.63.255.255131,070
16193.64.0.0/1593.64.0.1 to 93.65.255.25493.65.255.255131,070
16293.66.0.0/1593.66.0.1 to 93.67.255.25493.67.255.255131,070
16393.68.0.0/1593.68.0.1 to 93.69.255.25493.69.255.255131,070
16493.70.0.0/1593.70.0.1 to 93.71.255.25493.71.255.255131,070
16593.72.0.0/1593.72.0.1 to 93.73.255.25493.73.255.255131,070
16693.74.0.0/1593.74.0.1 to 93.75.255.25493.75.255.255131,070
16793.76.0.0/1593.76.0.1 to 93.77.255.25493.77.255.255131,070
16893.78.0.0/1593.78.0.1 to 93.79.255.25493.79.255.255131,070
16993.80.0.0/1593.80.0.1 to 93.81.255.25493.81.255.255131,070
17093.82.0.0/1593.82.0.1 to 93.83.255.25493.83.255.255131,070
17193.84.0.0/1593.84.0.1 to 93.85.255.25493.85.255.255131,070
17293.86.0.0/1593.86.0.1 to 93.87.255.25493.87.255.255131,070
17393.88.0.0/1593.88.0.1 to 93.89.255.25493.89.255.255131,070
17493.90.0.0/1593.90.0.1 to 93.91.255.25493.91.255.255131,070
17593.92.0.0/1593.92.0.1 to 93.93.255.25493.93.255.255131,070
17693.94.0.0/1593.94.0.1 to 93.95.255.25493.95.255.255131,070
17793.96.0.0/1593.96.0.1 to 93.97.255.25493.97.255.255131,070
17893.98.0.0/1593.98.0.1 to 93.99.255.25493.99.255.255131,070
17993.100.0.0/1593.100.0.1 to 93.101.255.25493.101.255.255131,070
18093.102.0.0/1593.102.0.1 to 93.103.255.25493.103.255.255131,070
18193.104.0.0/1593.104.0.1 to 93.105.255.25493.105.255.255131,070
18293.106.0.0/1593.106.0.1 to 93.107.255.25493.107.255.255131,070
18393.108.0.0/1593.108.0.1 to 93.109.255.25493.109.255.255131,070
18493.110.0.0/1593.110.0.1 to 93.111.255.25493.111.255.255131,070
18593.112.0.0/1593.112.0.1 to 93.113.255.25493.113.255.255131,070
18693.114.0.0/1593.114.0.1 to 93.115.255.25493.115.255.255131,070
18793.116.0.0/1593.116.0.1 to 93.117.255.25493.117.255.255131,070
18893.118.0.0/1593.118.0.1 to 93.119.255.25493.119.255.255131,070
18993.120.0.0/1593.120.0.1 to 93.121.255.25493.121.255.255131,070
19093.122.0.0/1593.122.0.1 to 93.123.255.25493.123.255.255131,070
19193.124.0.0/1593.124.0.1 to 93.125.255.25493.125.255.255131,070
19293.126.0.0/1593.126.0.1 to 93.127.255.25493.127.255.255131,070
19393.128.0.0/1593.128.0.1 to 93.129.255.25493.129.255.255131,070
19493.130.0.0/1593.130.0.1 to 93.131.255.25493.131.255.255131,070
19593.132.0.0/1593.132.0.1 to 93.133.255.25493.133.255.255131,070
19693.134.0.0/1593.134.0.1 to 93.135.255.25493.135.255.255131,070
19793.136.0.0/1593.136.0.1 to 93.137.255.25493.137.255.255131,070
19893.138.0.0/1593.138.0.1 to 93.139.255.25493.139.255.255131,070
19993.140.0.0/1593.140.0.1 to 93.141.255.25493.141.255.255131,070
20093.142.0.0/1593.142.0.1 to 93.143.255.25493.143.255.255131,070
20193.144.0.0/1593.144.0.1 to 93.145.255.25493.145.255.255131,070
20293.146.0.0/1593.146.0.1 to 93.147.255.25493.147.255.255131,070
20393.148.0.0/1593.148.0.1 to 93.149.255.25493.149.255.255131,070
20493.150.0.0/1593.150.0.1 to 93.151.255.25493.151.255.255131,070
20593.152.0.0/1593.152.0.1 to 93.153.255.25493.153.255.255131,070
20693.154.0.0/1593.154.0.1 to 93.155.255.25493.155.255.255131,070
20793.156.0.0/1593.156.0.1 to 93.157.255.25493.157.255.255131,070
20893.158.0.0/1593.158.0.1 to 93.159.255.25493.159.255.255131,070
20993.160.0.0/1593.160.0.1 to 93.161.255.25493.161.255.255131,070
21093.162.0.0/1593.162.0.1 to 93.163.255.25493.163.255.255131,070
21193.164.0.0/1593.164.0.1 to 93.165.255.25493.165.255.255131,070
21293.166.0.0/1593.166.0.1 to 93.167.255.25493.167.255.255131,070
21393.168.0.0/1593.168.0.1 to 93.169.255.25493.169.255.255131,070
21493.170.0.0/1593.170.0.1 to 93.171.255.25493.171.255.255131,070
21593.172.0.0/1593.172.0.1 to 93.173.255.25493.173.255.255131,070
21693.174.0.0/1593.174.0.1 to 93.175.255.25493.175.255.255131,070
21793.176.0.0/1593.176.0.1 to 93.177.255.25493.177.255.255131,070
21893.178.0.0/1593.178.0.1 to 93.179.255.25493.179.255.255131,070
21993.180.0.0/1593.180.0.1 to 93.181.255.25493.181.255.255131,070
22093.182.0.0/1593.182.0.1 to 93.183.255.25493.183.255.255131,070
22193.184.0.0/1593.184.0.1 to 93.185.255.25493.185.255.255131,070
22293.186.0.0/1593.186.0.1 to 93.187.255.25493.187.255.255131,070
22393.188.0.0/1593.188.0.1 to 93.189.255.25493.189.255.255131,070
22493.190.0.0/1593.190.0.1 to 93.191.255.25493.191.255.255131,070
22593.192.0.0/1593.192.0.1 to 93.193.255.25493.193.255.255131,070
22693.194.0.0/1593.194.0.1 to 93.195.255.25493.195.255.255131,070
22793.196.0.0/1593.196.0.1 to 93.197.255.25493.197.255.255131,070
22893.198.0.0/1593.198.0.1 to 93.199.255.25493.199.255.255131,070
22993.200.0.0/1593.200.0.1 to 93.201.255.25493.201.255.255131,070
23093.202.0.0/1593.202.0.1 to 93.203.255.25493.203.255.255131,070
23193.204.0.0/1593.204.0.1 to 93.205.255.25493.205.255.255131,070
23293.206.0.0/1593.206.0.1 to 93.207.255.25493.207.255.255131,070
23393.208.0.0/1593.208.0.1 to 93.209.255.25493.209.255.255131,070
23493.210.0.0/1593.210.0.1 to 93.211.255.25493.211.255.255131,070
23593.212.0.0/1593.212.0.1 to 93.213.255.25493.213.255.255131,070
23693.214.0.0/1593.214.0.1 to 93.215.255.25493.215.255.255131,070
23793.216.0.0/1593.216.0.1 to 93.217.255.25493.217.255.255131,070
23893.218.0.0/1593.218.0.1 to 93.219.255.25493.219.255.255131,070
23993.220.0.0/1593.220.0.1 to 93.221.255.25493.221.255.255131,070
24093.222.0.0/1593.222.0.1 to 93.223.255.25493.223.255.255131,070
24193.224.0.0/1593.224.0.1 to 93.225.255.25493.225.255.255131,070
24293.226.0.0/1593.226.0.1 to 93.227.255.25493.227.255.255131,070
24393.228.0.0/1593.228.0.1 to 93.229.255.25493.229.255.255131,070
24493.230.0.0/1593.230.0.1 to 93.231.255.25493.231.255.255131,070
24593.232.0.0/1593.232.0.1 to 93.233.255.25493.233.255.255131,070
24693.234.0.0/1593.234.0.1 to 93.235.255.25493.235.255.255131,070
24793.236.0.0/1593.236.0.1 to 93.237.255.25493.237.255.255131,070
24893.238.0.0/1593.238.0.1 to 93.239.255.25493.239.255.255131,070
24993.240.0.0/1593.240.0.1 to 93.241.255.25493.241.255.255131,070
25093.242.0.0/1593.242.0.1 to 93.243.255.25493.243.255.255131,070
25193.244.0.0/1593.244.0.1 to 93.245.255.25493.245.255.255131,070
25293.246.0.0/1593.246.0.1 to 93.247.255.25493.247.255.255131,070
25393.248.0.0/1593.248.0.1 to 93.249.255.25493.249.255.255131,070
25493.250.0.0/1593.250.0.1 to 93.251.255.25493.251.255.255131,070
25593.252.0.0/1593.252.0.1 to 93.253.255.25493.253.255.255131,070
25693.254.0.0/1593.254.0.1 to 93.255.255.25493.255.255.255131,070

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.