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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.

Network52.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
52.0.0.0
Broadcast address
52.255.255.255
First usable
52.0.0.1
Last usable
52.255.255.254
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 34000000 · Integer 872415232 to 889192447
Reverse DNS zone
52.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110100..00000000.00000000.0000000052.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network00110100..00000000.00000000.0000000052.0.0.0
Broadcast00110100..11111111.11111111.1111111152.255.255.255
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)

52.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
152.0.0.0/1652.0.0.1 to 52.0.255.25452.0.255.25565,534
252.1.0.0/1652.1.0.1 to 52.1.255.25452.1.255.25565,534
352.2.0.0/1652.2.0.1 to 52.2.255.25452.2.255.25565,534
452.3.0.0/1652.3.0.1 to 52.3.255.25452.3.255.25565,534
552.4.0.0/1652.4.0.1 to 52.4.255.25452.4.255.25565,534
652.5.0.0/1652.5.0.1 to 52.5.255.25452.5.255.25565,534
752.6.0.0/1652.6.0.1 to 52.6.255.25452.6.255.25565,534
852.7.0.0/1652.7.0.1 to 52.7.255.25452.7.255.25565,534
952.8.0.0/1652.8.0.1 to 52.8.255.25452.8.255.25565,534
1052.9.0.0/1652.9.0.1 to 52.9.255.25452.9.255.25565,534
1152.10.0.0/1652.10.0.1 to 52.10.255.25452.10.255.25565,534
1252.11.0.0/1652.11.0.1 to 52.11.255.25452.11.255.25565,534
1352.12.0.0/1652.12.0.1 to 52.12.255.25452.12.255.25565,534
1452.13.0.0/1652.13.0.1 to 52.13.255.25452.13.255.25565,534
1552.14.0.0/1652.14.0.1 to 52.14.255.25452.14.255.25565,534
1652.15.0.0/1652.15.0.1 to 52.15.255.25452.15.255.25565,534
1752.16.0.0/1652.16.0.1 to 52.16.255.25452.16.255.25565,534
1852.17.0.0/1652.17.0.1 to 52.17.255.25452.17.255.25565,534
1952.18.0.0/1652.18.0.1 to 52.18.255.25452.18.255.25565,534
2052.19.0.0/1652.19.0.1 to 52.19.255.25452.19.255.25565,534
2152.20.0.0/1652.20.0.1 to 52.20.255.25452.20.255.25565,534
2252.21.0.0/1652.21.0.1 to 52.21.255.25452.21.255.25565,534
2352.22.0.0/1652.22.0.1 to 52.22.255.25452.22.255.25565,534
2452.23.0.0/1652.23.0.1 to 52.23.255.25452.23.255.25565,534
2552.24.0.0/1652.24.0.1 to 52.24.255.25452.24.255.25565,534
2652.25.0.0/1652.25.0.1 to 52.25.255.25452.25.255.25565,534
2752.26.0.0/1652.26.0.1 to 52.26.255.25452.26.255.25565,534
2852.27.0.0/1652.27.0.1 to 52.27.255.25452.27.255.25565,534
2952.28.0.0/1652.28.0.1 to 52.28.255.25452.28.255.25565,534
3052.29.0.0/1652.29.0.1 to 52.29.255.25452.29.255.25565,534
3152.30.0.0/1652.30.0.1 to 52.30.255.25452.30.255.25565,534
3252.31.0.0/1652.31.0.1 to 52.31.255.25452.31.255.25565,534
3352.32.0.0/1652.32.0.1 to 52.32.255.25452.32.255.25565,534
3452.33.0.0/1652.33.0.1 to 52.33.255.25452.33.255.25565,534
3552.34.0.0/1652.34.0.1 to 52.34.255.25452.34.255.25565,534
3652.35.0.0/1652.35.0.1 to 52.35.255.25452.35.255.25565,534
3752.36.0.0/1652.36.0.1 to 52.36.255.25452.36.255.25565,534
3852.37.0.0/1652.37.0.1 to 52.37.255.25452.37.255.25565,534
3952.38.0.0/1652.38.0.1 to 52.38.255.25452.38.255.25565,534
4052.39.0.0/1652.39.0.1 to 52.39.255.25452.39.255.25565,534
4152.40.0.0/1652.40.0.1 to 52.40.255.25452.40.255.25565,534
4252.41.0.0/1652.41.0.1 to 52.41.255.25452.41.255.25565,534
4352.42.0.0/1652.42.0.1 to 52.42.255.25452.42.255.25565,534
4452.43.0.0/1652.43.0.1 to 52.43.255.25452.43.255.25565,534
4552.44.0.0/1652.44.0.1 to 52.44.255.25452.44.255.25565,534
4652.45.0.0/1652.45.0.1 to 52.45.255.25452.45.255.25565,534
4752.46.0.0/1652.46.0.1 to 52.46.255.25452.46.255.25565,534
4852.47.0.0/1652.47.0.1 to 52.47.255.25452.47.255.25565,534
4952.48.0.0/1652.48.0.1 to 52.48.255.25452.48.255.25565,534
5052.49.0.0/1652.49.0.1 to 52.49.255.25452.49.255.25565,534
5152.50.0.0/1652.50.0.1 to 52.50.255.25452.50.255.25565,534
5252.51.0.0/1652.51.0.1 to 52.51.255.25452.51.255.25565,534
5352.52.0.0/1652.52.0.1 to 52.52.255.25452.52.255.25565,534
5452.53.0.0/1652.53.0.1 to 52.53.255.25452.53.255.25565,534
5552.54.0.0/1652.54.0.1 to 52.54.255.25452.54.255.25565,534
5652.55.0.0/1652.55.0.1 to 52.55.255.25452.55.255.25565,534
5752.56.0.0/1652.56.0.1 to 52.56.255.25452.56.255.25565,534
5852.57.0.0/1652.57.0.1 to 52.57.255.25452.57.255.25565,534
5952.58.0.0/1652.58.0.1 to 52.58.255.25452.58.255.25565,534
6052.59.0.0/1652.59.0.1 to 52.59.255.25452.59.255.25565,534
6152.60.0.0/1652.60.0.1 to 52.60.255.25452.60.255.25565,534
6252.61.0.0/1652.61.0.1 to 52.61.255.25452.61.255.25565,534
6352.62.0.0/1652.62.0.1 to 52.62.255.25452.62.255.25565,534
6452.63.0.0/1652.63.0.1 to 52.63.255.25452.63.255.25565,534
6552.64.0.0/1652.64.0.1 to 52.64.255.25452.64.255.25565,534
6652.65.0.0/1652.65.0.1 to 52.65.255.25452.65.255.25565,534
6752.66.0.0/1652.66.0.1 to 52.66.255.25452.66.255.25565,534
6852.67.0.0/1652.67.0.1 to 52.67.255.25452.67.255.25565,534
6952.68.0.0/1652.68.0.1 to 52.68.255.25452.68.255.25565,534
7052.69.0.0/1652.69.0.1 to 52.69.255.25452.69.255.25565,534
7152.70.0.0/1652.70.0.1 to 52.70.255.25452.70.255.25565,534
7252.71.0.0/1652.71.0.1 to 52.71.255.25452.71.255.25565,534
7352.72.0.0/1652.72.0.1 to 52.72.255.25452.72.255.25565,534
7452.73.0.0/1652.73.0.1 to 52.73.255.25452.73.255.25565,534
7552.74.0.0/1652.74.0.1 to 52.74.255.25452.74.255.25565,534
7652.75.0.0/1652.75.0.1 to 52.75.255.25452.75.255.25565,534
7752.76.0.0/1652.76.0.1 to 52.76.255.25452.76.255.25565,534
7852.77.0.0/1652.77.0.1 to 52.77.255.25452.77.255.25565,534
7952.78.0.0/1652.78.0.1 to 52.78.255.25452.78.255.25565,534
8052.79.0.0/1652.79.0.1 to 52.79.255.25452.79.255.25565,534
8152.80.0.0/1652.80.0.1 to 52.80.255.25452.80.255.25565,534
8252.81.0.0/1652.81.0.1 to 52.81.255.25452.81.255.25565,534
8352.82.0.0/1652.82.0.1 to 52.82.255.25452.82.255.25565,534
8452.83.0.0/1652.83.0.1 to 52.83.255.25452.83.255.25565,534
8552.84.0.0/1652.84.0.1 to 52.84.255.25452.84.255.25565,534
8652.85.0.0/1652.85.0.1 to 52.85.255.25452.85.255.25565,534
8752.86.0.0/1652.86.0.1 to 52.86.255.25452.86.255.25565,534
8852.87.0.0/1652.87.0.1 to 52.87.255.25452.87.255.25565,534
8952.88.0.0/1652.88.0.1 to 52.88.255.25452.88.255.25565,534
9052.89.0.0/1652.89.0.1 to 52.89.255.25452.89.255.25565,534
9152.90.0.0/1652.90.0.1 to 52.90.255.25452.90.255.25565,534
9252.91.0.0/1652.91.0.1 to 52.91.255.25452.91.255.25565,534
9352.92.0.0/1652.92.0.1 to 52.92.255.25452.92.255.25565,534
9452.93.0.0/1652.93.0.1 to 52.93.255.25452.93.255.25565,534
9552.94.0.0/1652.94.0.1 to 52.94.255.25452.94.255.25565,534
9652.95.0.0/1652.95.0.1 to 52.95.255.25452.95.255.25565,534
9752.96.0.0/1652.96.0.1 to 52.96.255.25452.96.255.25565,534
9852.97.0.0/1652.97.0.1 to 52.97.255.25452.97.255.25565,534
9952.98.0.0/1652.98.0.1 to 52.98.255.25452.98.255.25565,534
10052.99.0.0/1652.99.0.1 to 52.99.255.25452.99.255.25565,534
10152.100.0.0/1652.100.0.1 to 52.100.255.25452.100.255.25565,534
10252.101.0.0/1652.101.0.1 to 52.101.255.25452.101.255.25565,534
10352.102.0.0/1652.102.0.1 to 52.102.255.25452.102.255.25565,534
10452.103.0.0/1652.103.0.1 to 52.103.255.25452.103.255.25565,534
10552.104.0.0/1652.104.0.1 to 52.104.255.25452.104.255.25565,534
10652.105.0.0/1652.105.0.1 to 52.105.255.25452.105.255.25565,534
10752.106.0.0/1652.106.0.1 to 52.106.255.25452.106.255.25565,534
10852.107.0.0/1652.107.0.1 to 52.107.255.25452.107.255.25565,534
10952.108.0.0/1652.108.0.1 to 52.108.255.25452.108.255.25565,534
11052.109.0.0/1652.109.0.1 to 52.109.255.25452.109.255.25565,534
11152.110.0.0/1652.110.0.1 to 52.110.255.25452.110.255.25565,534
11252.111.0.0/1652.111.0.1 to 52.111.255.25452.111.255.25565,534
11352.112.0.0/1652.112.0.1 to 52.112.255.25452.112.255.25565,534
11452.113.0.0/1652.113.0.1 to 52.113.255.25452.113.255.25565,534
11552.114.0.0/1652.114.0.1 to 52.114.255.25452.114.255.25565,534
11652.115.0.0/1652.115.0.1 to 52.115.255.25452.115.255.25565,534
11752.116.0.0/1652.116.0.1 to 52.116.255.25452.116.255.25565,534
11852.117.0.0/1652.117.0.1 to 52.117.255.25452.117.255.25565,534
11952.118.0.0/1652.118.0.1 to 52.118.255.25452.118.255.25565,534
12052.119.0.0/1652.119.0.1 to 52.119.255.25452.119.255.25565,534
12152.120.0.0/1652.120.0.1 to 52.120.255.25452.120.255.25565,534
12252.121.0.0/1652.121.0.1 to 52.121.255.25452.121.255.25565,534
12352.122.0.0/1652.122.0.1 to 52.122.255.25452.122.255.25565,534
12452.123.0.0/1652.123.0.1 to 52.123.255.25452.123.255.25565,534
12552.124.0.0/1652.124.0.1 to 52.124.255.25452.124.255.25565,534
12652.125.0.0/1652.125.0.1 to 52.125.255.25452.125.255.25565,534
12752.126.0.0/1652.126.0.1 to 52.126.255.25452.126.255.25565,534
12852.127.0.0/1652.127.0.1 to 52.127.255.25452.127.255.25565,534
12952.128.0.0/1652.128.0.1 to 52.128.255.25452.128.255.25565,534
13052.129.0.0/1652.129.0.1 to 52.129.255.25452.129.255.25565,534
13152.130.0.0/1652.130.0.1 to 52.130.255.25452.130.255.25565,534
13252.131.0.0/1652.131.0.1 to 52.131.255.25452.131.255.25565,534
13352.132.0.0/1652.132.0.1 to 52.132.255.25452.132.255.25565,534
13452.133.0.0/1652.133.0.1 to 52.133.255.25452.133.255.25565,534
13552.134.0.0/1652.134.0.1 to 52.134.255.25452.134.255.25565,534
13652.135.0.0/1652.135.0.1 to 52.135.255.25452.135.255.25565,534
13752.136.0.0/1652.136.0.1 to 52.136.255.25452.136.255.25565,534
13852.137.0.0/1652.137.0.1 to 52.137.255.25452.137.255.25565,534
13952.138.0.0/1652.138.0.1 to 52.138.255.25452.138.255.25565,534
14052.139.0.0/1652.139.0.1 to 52.139.255.25452.139.255.25565,534
14152.140.0.0/1652.140.0.1 to 52.140.255.25452.140.255.25565,534
14252.141.0.0/1652.141.0.1 to 52.141.255.25452.141.255.25565,534
14352.142.0.0/1652.142.0.1 to 52.142.255.25452.142.255.25565,534
14452.143.0.0/1652.143.0.1 to 52.143.255.25452.143.255.25565,534
14552.144.0.0/1652.144.0.1 to 52.144.255.25452.144.255.25565,534
14652.145.0.0/1652.145.0.1 to 52.145.255.25452.145.255.25565,534
14752.146.0.0/1652.146.0.1 to 52.146.255.25452.146.255.25565,534
14852.147.0.0/1652.147.0.1 to 52.147.255.25452.147.255.25565,534
14952.148.0.0/1652.148.0.1 to 52.148.255.25452.148.255.25565,534
15052.149.0.0/1652.149.0.1 to 52.149.255.25452.149.255.25565,534
15152.150.0.0/1652.150.0.1 to 52.150.255.25452.150.255.25565,534
15252.151.0.0/1652.151.0.1 to 52.151.255.25452.151.255.25565,534
15352.152.0.0/1652.152.0.1 to 52.152.255.25452.152.255.25565,534
15452.153.0.0/1652.153.0.1 to 52.153.255.25452.153.255.25565,534
15552.154.0.0/1652.154.0.1 to 52.154.255.25452.154.255.25565,534
15652.155.0.0/1652.155.0.1 to 52.155.255.25452.155.255.25565,534
15752.156.0.0/1652.156.0.1 to 52.156.255.25452.156.255.25565,534
15852.157.0.0/1652.157.0.1 to 52.157.255.25452.157.255.25565,534
15952.158.0.0/1652.158.0.1 to 52.158.255.25452.158.255.25565,534
16052.159.0.0/1652.159.0.1 to 52.159.255.25452.159.255.25565,534
16152.160.0.0/1652.160.0.1 to 52.160.255.25452.160.255.25565,534
16252.161.0.0/1652.161.0.1 to 52.161.255.25452.161.255.25565,534
16352.162.0.0/1652.162.0.1 to 52.162.255.25452.162.255.25565,534
16452.163.0.0/1652.163.0.1 to 52.163.255.25452.163.255.25565,534
16552.164.0.0/1652.164.0.1 to 52.164.255.25452.164.255.25565,534
16652.165.0.0/1652.165.0.1 to 52.165.255.25452.165.255.25565,534
16752.166.0.0/1652.166.0.1 to 52.166.255.25452.166.255.25565,534
16852.167.0.0/1652.167.0.1 to 52.167.255.25452.167.255.25565,534
16952.168.0.0/1652.168.0.1 to 52.168.255.25452.168.255.25565,534
17052.169.0.0/1652.169.0.1 to 52.169.255.25452.169.255.25565,534
17152.170.0.0/1652.170.0.1 to 52.170.255.25452.170.255.25565,534
17252.171.0.0/1652.171.0.1 to 52.171.255.25452.171.255.25565,534
17352.172.0.0/1652.172.0.1 to 52.172.255.25452.172.255.25565,534
17452.173.0.0/1652.173.0.1 to 52.173.255.25452.173.255.25565,534
17552.174.0.0/1652.174.0.1 to 52.174.255.25452.174.255.25565,534
17652.175.0.0/1652.175.0.1 to 52.175.255.25452.175.255.25565,534
17752.176.0.0/1652.176.0.1 to 52.176.255.25452.176.255.25565,534
17852.177.0.0/1652.177.0.1 to 52.177.255.25452.177.255.25565,534
17952.178.0.0/1652.178.0.1 to 52.178.255.25452.178.255.25565,534
18052.179.0.0/1652.179.0.1 to 52.179.255.25452.179.255.25565,534
18152.180.0.0/1652.180.0.1 to 52.180.255.25452.180.255.25565,534
18252.181.0.0/1652.181.0.1 to 52.181.255.25452.181.255.25565,534
18352.182.0.0/1652.182.0.1 to 52.182.255.25452.182.255.25565,534
18452.183.0.0/1652.183.0.1 to 52.183.255.25452.183.255.25565,534
18552.184.0.0/1652.184.0.1 to 52.184.255.25452.184.255.25565,534
18652.185.0.0/1652.185.0.1 to 52.185.255.25452.185.255.25565,534
18752.186.0.0/1652.186.0.1 to 52.186.255.25452.186.255.25565,534
18852.187.0.0/1652.187.0.1 to 52.187.255.25452.187.255.25565,534
18952.188.0.0/1652.188.0.1 to 52.188.255.25452.188.255.25565,534
19052.189.0.0/1652.189.0.1 to 52.189.255.25452.189.255.25565,534
19152.190.0.0/1652.190.0.1 to 52.190.255.25452.190.255.25565,534
19252.191.0.0/1652.191.0.1 to 52.191.255.25452.191.255.25565,534
19352.192.0.0/1652.192.0.1 to 52.192.255.25452.192.255.25565,534
19452.193.0.0/1652.193.0.1 to 52.193.255.25452.193.255.25565,534
19552.194.0.0/1652.194.0.1 to 52.194.255.25452.194.255.25565,534
19652.195.0.0/1652.195.0.1 to 52.195.255.25452.195.255.25565,534
19752.196.0.0/1652.196.0.1 to 52.196.255.25452.196.255.25565,534
19852.197.0.0/1652.197.0.1 to 52.197.255.25452.197.255.25565,534
19952.198.0.0/1652.198.0.1 to 52.198.255.25452.198.255.25565,534
20052.199.0.0/1652.199.0.1 to 52.199.255.25452.199.255.25565,534
20152.200.0.0/1652.200.0.1 to 52.200.255.25452.200.255.25565,534
20252.201.0.0/1652.201.0.1 to 52.201.255.25452.201.255.25565,534
20352.202.0.0/1652.202.0.1 to 52.202.255.25452.202.255.25565,534
20452.203.0.0/1652.203.0.1 to 52.203.255.25452.203.255.25565,534
20552.204.0.0/1652.204.0.1 to 52.204.255.25452.204.255.25565,534
20652.205.0.0/1652.205.0.1 to 52.205.255.25452.205.255.25565,534
20752.206.0.0/1652.206.0.1 to 52.206.255.25452.206.255.25565,534
20852.207.0.0/1652.207.0.1 to 52.207.255.25452.207.255.25565,534
20952.208.0.0/1652.208.0.1 to 52.208.255.25452.208.255.25565,534
21052.209.0.0/1652.209.0.1 to 52.209.255.25452.209.255.25565,534
21152.210.0.0/1652.210.0.1 to 52.210.255.25452.210.255.25565,534
21252.211.0.0/1652.211.0.1 to 52.211.255.25452.211.255.25565,534
21352.212.0.0/1652.212.0.1 to 52.212.255.25452.212.255.25565,534
21452.213.0.0/1652.213.0.1 to 52.213.255.25452.213.255.25565,534
21552.214.0.0/1652.214.0.1 to 52.214.255.25452.214.255.25565,534
21652.215.0.0/1652.215.0.1 to 52.215.255.25452.215.255.25565,534
21752.216.0.0/1652.216.0.1 to 52.216.255.25452.216.255.25565,534
21852.217.0.0/1652.217.0.1 to 52.217.255.25452.217.255.25565,534
21952.218.0.0/1652.218.0.1 to 52.218.255.25452.218.255.25565,534
22052.219.0.0/1652.219.0.1 to 52.219.255.25452.219.255.25565,534
22152.220.0.0/1652.220.0.1 to 52.220.255.25452.220.255.25565,534
22252.221.0.0/1652.221.0.1 to 52.221.255.25452.221.255.25565,534
22352.222.0.0/1652.222.0.1 to 52.222.255.25452.222.255.25565,534
22452.223.0.0/1652.223.0.1 to 52.223.255.25452.223.255.25565,534
22552.224.0.0/1652.224.0.1 to 52.224.255.25452.224.255.25565,534
22652.225.0.0/1652.225.0.1 to 52.225.255.25452.225.255.25565,534
22752.226.0.0/1652.226.0.1 to 52.226.255.25452.226.255.25565,534
22852.227.0.0/1652.227.0.1 to 52.227.255.25452.227.255.25565,534
22952.228.0.0/1652.228.0.1 to 52.228.255.25452.228.255.25565,534
23052.229.0.0/1652.229.0.1 to 52.229.255.25452.229.255.25565,534
23152.230.0.0/1652.230.0.1 to 52.230.255.25452.230.255.25565,534
23252.231.0.0/1652.231.0.1 to 52.231.255.25452.231.255.25565,534
23352.232.0.0/1652.232.0.1 to 52.232.255.25452.232.255.25565,534
23452.233.0.0/1652.233.0.1 to 52.233.255.25452.233.255.25565,534
23552.234.0.0/1652.234.0.1 to 52.234.255.25452.234.255.25565,534
23652.235.0.0/1652.235.0.1 to 52.235.255.25452.235.255.25565,534
23752.236.0.0/1652.236.0.1 to 52.236.255.25452.236.255.25565,534
23852.237.0.0/1652.237.0.1 to 52.237.255.25452.237.255.25565,534
23952.238.0.0/1652.238.0.1 to 52.238.255.25452.238.255.25565,534
24052.239.0.0/1652.239.0.1 to 52.239.255.25452.239.255.25565,534
24152.240.0.0/1652.240.0.1 to 52.240.255.25452.240.255.25565,534
24252.241.0.0/1652.241.0.1 to 52.241.255.25452.241.255.25565,534
24352.242.0.0/1652.242.0.1 to 52.242.255.25452.242.255.25565,534
24452.243.0.0/1652.243.0.1 to 52.243.255.25452.243.255.25565,534
24552.244.0.0/1652.244.0.1 to 52.244.255.25452.244.255.25565,534
24652.245.0.0/1652.245.0.1 to 52.245.255.25452.245.255.25565,534
24752.246.0.0/1652.246.0.1 to 52.246.255.25452.246.255.25565,534
24852.247.0.0/1652.247.0.1 to 52.247.255.25452.247.255.25565,534
24952.248.0.0/1652.248.0.1 to 52.248.255.25452.248.255.25565,534
25052.249.0.0/1652.249.0.1 to 52.249.255.25452.249.255.25565,534
25152.250.0.0/1652.250.0.1 to 52.250.255.25452.250.255.25565,534
25252.251.0.0/1652.251.0.1 to 52.251.255.25452.251.255.25565,534
25352.252.0.0/1652.252.0.1 to 52.252.255.25452.252.255.25565,534
25452.253.0.0/1652.253.0.1 to 52.253.255.25452.253.255.25565,534
25552.254.0.0/1652.254.0.1 to 52.254.255.25452.254.255.25565,534
25652.255.0.0/1652.255.0.1 to 52.255.255.25452.255.255.25565,534

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.