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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.

Network78.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
78.0.0.0
Broadcast address
78.255.255.255
First usable
78.0.0.1
Last usable
78.255.255.254
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 4E000000 · Integer 1308622848 to 1325400063
Reverse DNS zone
78.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01001110..00000000.00000000.0000000078.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01001110..00000000.00000000.0000000078.0.0.0
Broadcast01001110..11111111.11111111.1111111178.255.255.255
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)

78.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
178.0.0.0/1678.0.0.1 to 78.0.255.25478.0.255.25565,534
278.1.0.0/1678.1.0.1 to 78.1.255.25478.1.255.25565,534
378.2.0.0/1678.2.0.1 to 78.2.255.25478.2.255.25565,534
478.3.0.0/1678.3.0.1 to 78.3.255.25478.3.255.25565,534
578.4.0.0/1678.4.0.1 to 78.4.255.25478.4.255.25565,534
678.5.0.0/1678.5.0.1 to 78.5.255.25478.5.255.25565,534
778.6.0.0/1678.6.0.1 to 78.6.255.25478.6.255.25565,534
878.7.0.0/1678.7.0.1 to 78.7.255.25478.7.255.25565,534
978.8.0.0/1678.8.0.1 to 78.8.255.25478.8.255.25565,534
1078.9.0.0/1678.9.0.1 to 78.9.255.25478.9.255.25565,534
1178.10.0.0/1678.10.0.1 to 78.10.255.25478.10.255.25565,534
1278.11.0.0/1678.11.0.1 to 78.11.255.25478.11.255.25565,534
1378.12.0.0/1678.12.0.1 to 78.12.255.25478.12.255.25565,534
1478.13.0.0/1678.13.0.1 to 78.13.255.25478.13.255.25565,534
1578.14.0.0/1678.14.0.1 to 78.14.255.25478.14.255.25565,534
1678.15.0.0/1678.15.0.1 to 78.15.255.25478.15.255.25565,534
1778.16.0.0/1678.16.0.1 to 78.16.255.25478.16.255.25565,534
1878.17.0.0/1678.17.0.1 to 78.17.255.25478.17.255.25565,534
1978.18.0.0/1678.18.0.1 to 78.18.255.25478.18.255.25565,534
2078.19.0.0/1678.19.0.1 to 78.19.255.25478.19.255.25565,534
2178.20.0.0/1678.20.0.1 to 78.20.255.25478.20.255.25565,534
2278.21.0.0/1678.21.0.1 to 78.21.255.25478.21.255.25565,534
2378.22.0.0/1678.22.0.1 to 78.22.255.25478.22.255.25565,534
2478.23.0.0/1678.23.0.1 to 78.23.255.25478.23.255.25565,534
2578.24.0.0/1678.24.0.1 to 78.24.255.25478.24.255.25565,534
2678.25.0.0/1678.25.0.1 to 78.25.255.25478.25.255.25565,534
2778.26.0.0/1678.26.0.1 to 78.26.255.25478.26.255.25565,534
2878.27.0.0/1678.27.0.1 to 78.27.255.25478.27.255.25565,534
2978.28.0.0/1678.28.0.1 to 78.28.255.25478.28.255.25565,534
3078.29.0.0/1678.29.0.1 to 78.29.255.25478.29.255.25565,534
3178.30.0.0/1678.30.0.1 to 78.30.255.25478.30.255.25565,534
3278.31.0.0/1678.31.0.1 to 78.31.255.25478.31.255.25565,534
3378.32.0.0/1678.32.0.1 to 78.32.255.25478.32.255.25565,534
3478.33.0.0/1678.33.0.1 to 78.33.255.25478.33.255.25565,534
3578.34.0.0/1678.34.0.1 to 78.34.255.25478.34.255.25565,534
3678.35.0.0/1678.35.0.1 to 78.35.255.25478.35.255.25565,534
3778.36.0.0/1678.36.0.1 to 78.36.255.25478.36.255.25565,534
3878.37.0.0/1678.37.0.1 to 78.37.255.25478.37.255.25565,534
3978.38.0.0/1678.38.0.1 to 78.38.255.25478.38.255.25565,534
4078.39.0.0/1678.39.0.1 to 78.39.255.25478.39.255.25565,534
4178.40.0.0/1678.40.0.1 to 78.40.255.25478.40.255.25565,534
4278.41.0.0/1678.41.0.1 to 78.41.255.25478.41.255.25565,534
4378.42.0.0/1678.42.0.1 to 78.42.255.25478.42.255.25565,534
4478.43.0.0/1678.43.0.1 to 78.43.255.25478.43.255.25565,534
4578.44.0.0/1678.44.0.1 to 78.44.255.25478.44.255.25565,534
4678.45.0.0/1678.45.0.1 to 78.45.255.25478.45.255.25565,534
4778.46.0.0/1678.46.0.1 to 78.46.255.25478.46.255.25565,534
4878.47.0.0/1678.47.0.1 to 78.47.255.25478.47.255.25565,534
4978.48.0.0/1678.48.0.1 to 78.48.255.25478.48.255.25565,534
5078.49.0.0/1678.49.0.1 to 78.49.255.25478.49.255.25565,534
5178.50.0.0/1678.50.0.1 to 78.50.255.25478.50.255.25565,534
5278.51.0.0/1678.51.0.1 to 78.51.255.25478.51.255.25565,534
5378.52.0.0/1678.52.0.1 to 78.52.255.25478.52.255.25565,534
5478.53.0.0/1678.53.0.1 to 78.53.255.25478.53.255.25565,534
5578.54.0.0/1678.54.0.1 to 78.54.255.25478.54.255.25565,534
5678.55.0.0/1678.55.0.1 to 78.55.255.25478.55.255.25565,534
5778.56.0.0/1678.56.0.1 to 78.56.255.25478.56.255.25565,534
5878.57.0.0/1678.57.0.1 to 78.57.255.25478.57.255.25565,534
5978.58.0.0/1678.58.0.1 to 78.58.255.25478.58.255.25565,534
6078.59.0.0/1678.59.0.1 to 78.59.255.25478.59.255.25565,534
6178.60.0.0/1678.60.0.1 to 78.60.255.25478.60.255.25565,534
6278.61.0.0/1678.61.0.1 to 78.61.255.25478.61.255.25565,534
6378.62.0.0/1678.62.0.1 to 78.62.255.25478.62.255.25565,534
6478.63.0.0/1678.63.0.1 to 78.63.255.25478.63.255.25565,534
6578.64.0.0/1678.64.0.1 to 78.64.255.25478.64.255.25565,534
6678.65.0.0/1678.65.0.1 to 78.65.255.25478.65.255.25565,534
6778.66.0.0/1678.66.0.1 to 78.66.255.25478.66.255.25565,534
6878.67.0.0/1678.67.0.1 to 78.67.255.25478.67.255.25565,534
6978.68.0.0/1678.68.0.1 to 78.68.255.25478.68.255.25565,534
7078.69.0.0/1678.69.0.1 to 78.69.255.25478.69.255.25565,534
7178.70.0.0/1678.70.0.1 to 78.70.255.25478.70.255.25565,534
7278.71.0.0/1678.71.0.1 to 78.71.255.25478.71.255.25565,534
7378.72.0.0/1678.72.0.1 to 78.72.255.25478.72.255.25565,534
7478.73.0.0/1678.73.0.1 to 78.73.255.25478.73.255.25565,534
7578.74.0.0/1678.74.0.1 to 78.74.255.25478.74.255.25565,534
7678.75.0.0/1678.75.0.1 to 78.75.255.25478.75.255.25565,534
7778.76.0.0/1678.76.0.1 to 78.76.255.25478.76.255.25565,534
7878.77.0.0/1678.77.0.1 to 78.77.255.25478.77.255.25565,534
7978.78.0.0/1678.78.0.1 to 78.78.255.25478.78.255.25565,534
8078.79.0.0/1678.79.0.1 to 78.79.255.25478.79.255.25565,534
8178.80.0.0/1678.80.0.1 to 78.80.255.25478.80.255.25565,534
8278.81.0.0/1678.81.0.1 to 78.81.255.25478.81.255.25565,534
8378.82.0.0/1678.82.0.1 to 78.82.255.25478.82.255.25565,534
8478.83.0.0/1678.83.0.1 to 78.83.255.25478.83.255.25565,534
8578.84.0.0/1678.84.0.1 to 78.84.255.25478.84.255.25565,534
8678.85.0.0/1678.85.0.1 to 78.85.255.25478.85.255.25565,534
8778.86.0.0/1678.86.0.1 to 78.86.255.25478.86.255.25565,534
8878.87.0.0/1678.87.0.1 to 78.87.255.25478.87.255.25565,534
8978.88.0.0/1678.88.0.1 to 78.88.255.25478.88.255.25565,534
9078.89.0.0/1678.89.0.1 to 78.89.255.25478.89.255.25565,534
9178.90.0.0/1678.90.0.1 to 78.90.255.25478.90.255.25565,534
9278.91.0.0/1678.91.0.1 to 78.91.255.25478.91.255.25565,534
9378.92.0.0/1678.92.0.1 to 78.92.255.25478.92.255.25565,534
9478.93.0.0/1678.93.0.1 to 78.93.255.25478.93.255.25565,534
9578.94.0.0/1678.94.0.1 to 78.94.255.25478.94.255.25565,534
9678.95.0.0/1678.95.0.1 to 78.95.255.25478.95.255.25565,534
9778.96.0.0/1678.96.0.1 to 78.96.255.25478.96.255.25565,534
9878.97.0.0/1678.97.0.1 to 78.97.255.25478.97.255.25565,534
9978.98.0.0/1678.98.0.1 to 78.98.255.25478.98.255.25565,534
10078.99.0.0/1678.99.0.1 to 78.99.255.25478.99.255.25565,534
10178.100.0.0/1678.100.0.1 to 78.100.255.25478.100.255.25565,534
10278.101.0.0/1678.101.0.1 to 78.101.255.25478.101.255.25565,534
10378.102.0.0/1678.102.0.1 to 78.102.255.25478.102.255.25565,534
10478.103.0.0/1678.103.0.1 to 78.103.255.25478.103.255.25565,534
10578.104.0.0/1678.104.0.1 to 78.104.255.25478.104.255.25565,534
10678.105.0.0/1678.105.0.1 to 78.105.255.25478.105.255.25565,534
10778.106.0.0/1678.106.0.1 to 78.106.255.25478.106.255.25565,534
10878.107.0.0/1678.107.0.1 to 78.107.255.25478.107.255.25565,534
10978.108.0.0/1678.108.0.1 to 78.108.255.25478.108.255.25565,534
11078.109.0.0/1678.109.0.1 to 78.109.255.25478.109.255.25565,534
11178.110.0.0/1678.110.0.1 to 78.110.255.25478.110.255.25565,534
11278.111.0.0/1678.111.0.1 to 78.111.255.25478.111.255.25565,534
11378.112.0.0/1678.112.0.1 to 78.112.255.25478.112.255.25565,534
11478.113.0.0/1678.113.0.1 to 78.113.255.25478.113.255.25565,534
11578.114.0.0/1678.114.0.1 to 78.114.255.25478.114.255.25565,534
11678.115.0.0/1678.115.0.1 to 78.115.255.25478.115.255.25565,534
11778.116.0.0/1678.116.0.1 to 78.116.255.25478.116.255.25565,534
11878.117.0.0/1678.117.0.1 to 78.117.255.25478.117.255.25565,534
11978.118.0.0/1678.118.0.1 to 78.118.255.25478.118.255.25565,534
12078.119.0.0/1678.119.0.1 to 78.119.255.25478.119.255.25565,534
12178.120.0.0/1678.120.0.1 to 78.120.255.25478.120.255.25565,534
12278.121.0.0/1678.121.0.1 to 78.121.255.25478.121.255.25565,534
12378.122.0.0/1678.122.0.1 to 78.122.255.25478.122.255.25565,534
12478.123.0.0/1678.123.0.1 to 78.123.255.25478.123.255.25565,534
12578.124.0.0/1678.124.0.1 to 78.124.255.25478.124.255.25565,534
12678.125.0.0/1678.125.0.1 to 78.125.255.25478.125.255.25565,534
12778.126.0.0/1678.126.0.1 to 78.126.255.25478.126.255.25565,534
12878.127.0.0/1678.127.0.1 to 78.127.255.25478.127.255.25565,534
12978.128.0.0/1678.128.0.1 to 78.128.255.25478.128.255.25565,534
13078.129.0.0/1678.129.0.1 to 78.129.255.25478.129.255.25565,534
13178.130.0.0/1678.130.0.1 to 78.130.255.25478.130.255.25565,534
13278.131.0.0/1678.131.0.1 to 78.131.255.25478.131.255.25565,534
13378.132.0.0/1678.132.0.1 to 78.132.255.25478.132.255.25565,534
13478.133.0.0/1678.133.0.1 to 78.133.255.25478.133.255.25565,534
13578.134.0.0/1678.134.0.1 to 78.134.255.25478.134.255.25565,534
13678.135.0.0/1678.135.0.1 to 78.135.255.25478.135.255.25565,534
13778.136.0.0/1678.136.0.1 to 78.136.255.25478.136.255.25565,534
13878.137.0.0/1678.137.0.1 to 78.137.255.25478.137.255.25565,534
13978.138.0.0/1678.138.0.1 to 78.138.255.25478.138.255.25565,534
14078.139.0.0/1678.139.0.1 to 78.139.255.25478.139.255.25565,534
14178.140.0.0/1678.140.0.1 to 78.140.255.25478.140.255.25565,534
14278.141.0.0/1678.141.0.1 to 78.141.255.25478.141.255.25565,534
14378.142.0.0/1678.142.0.1 to 78.142.255.25478.142.255.25565,534
14478.143.0.0/1678.143.0.1 to 78.143.255.25478.143.255.25565,534
14578.144.0.0/1678.144.0.1 to 78.144.255.25478.144.255.25565,534
14678.145.0.0/1678.145.0.1 to 78.145.255.25478.145.255.25565,534
14778.146.0.0/1678.146.0.1 to 78.146.255.25478.146.255.25565,534
14878.147.0.0/1678.147.0.1 to 78.147.255.25478.147.255.25565,534
14978.148.0.0/1678.148.0.1 to 78.148.255.25478.148.255.25565,534
15078.149.0.0/1678.149.0.1 to 78.149.255.25478.149.255.25565,534
15178.150.0.0/1678.150.0.1 to 78.150.255.25478.150.255.25565,534
15278.151.0.0/1678.151.0.1 to 78.151.255.25478.151.255.25565,534
15378.152.0.0/1678.152.0.1 to 78.152.255.25478.152.255.25565,534
15478.153.0.0/1678.153.0.1 to 78.153.255.25478.153.255.25565,534
15578.154.0.0/1678.154.0.1 to 78.154.255.25478.154.255.25565,534
15678.155.0.0/1678.155.0.1 to 78.155.255.25478.155.255.25565,534
15778.156.0.0/1678.156.0.1 to 78.156.255.25478.156.255.25565,534
15878.157.0.0/1678.157.0.1 to 78.157.255.25478.157.255.25565,534
15978.158.0.0/1678.158.0.1 to 78.158.255.25478.158.255.25565,534
16078.159.0.0/1678.159.0.1 to 78.159.255.25478.159.255.25565,534
16178.160.0.0/1678.160.0.1 to 78.160.255.25478.160.255.25565,534
16278.161.0.0/1678.161.0.1 to 78.161.255.25478.161.255.25565,534
16378.162.0.0/1678.162.0.1 to 78.162.255.25478.162.255.25565,534
16478.163.0.0/1678.163.0.1 to 78.163.255.25478.163.255.25565,534
16578.164.0.0/1678.164.0.1 to 78.164.255.25478.164.255.25565,534
16678.165.0.0/1678.165.0.1 to 78.165.255.25478.165.255.25565,534
16778.166.0.0/1678.166.0.1 to 78.166.255.25478.166.255.25565,534
16878.167.0.0/1678.167.0.1 to 78.167.255.25478.167.255.25565,534
16978.168.0.0/1678.168.0.1 to 78.168.255.25478.168.255.25565,534
17078.169.0.0/1678.169.0.1 to 78.169.255.25478.169.255.25565,534
17178.170.0.0/1678.170.0.1 to 78.170.255.25478.170.255.25565,534
17278.171.0.0/1678.171.0.1 to 78.171.255.25478.171.255.25565,534
17378.172.0.0/1678.172.0.1 to 78.172.255.25478.172.255.25565,534
17478.173.0.0/1678.173.0.1 to 78.173.255.25478.173.255.25565,534
17578.174.0.0/1678.174.0.1 to 78.174.255.25478.174.255.25565,534
17678.175.0.0/1678.175.0.1 to 78.175.255.25478.175.255.25565,534
17778.176.0.0/1678.176.0.1 to 78.176.255.25478.176.255.25565,534
17878.177.0.0/1678.177.0.1 to 78.177.255.25478.177.255.25565,534
17978.178.0.0/1678.178.0.1 to 78.178.255.25478.178.255.25565,534
18078.179.0.0/1678.179.0.1 to 78.179.255.25478.179.255.25565,534
18178.180.0.0/1678.180.0.1 to 78.180.255.25478.180.255.25565,534
18278.181.0.0/1678.181.0.1 to 78.181.255.25478.181.255.25565,534
18378.182.0.0/1678.182.0.1 to 78.182.255.25478.182.255.25565,534
18478.183.0.0/1678.183.0.1 to 78.183.255.25478.183.255.25565,534
18578.184.0.0/1678.184.0.1 to 78.184.255.25478.184.255.25565,534
18678.185.0.0/1678.185.0.1 to 78.185.255.25478.185.255.25565,534
18778.186.0.0/1678.186.0.1 to 78.186.255.25478.186.255.25565,534
18878.187.0.0/1678.187.0.1 to 78.187.255.25478.187.255.25565,534
18978.188.0.0/1678.188.0.1 to 78.188.255.25478.188.255.25565,534
19078.189.0.0/1678.189.0.1 to 78.189.255.25478.189.255.25565,534
19178.190.0.0/1678.190.0.1 to 78.190.255.25478.190.255.25565,534
19278.191.0.0/1678.191.0.1 to 78.191.255.25478.191.255.25565,534
19378.192.0.0/1678.192.0.1 to 78.192.255.25478.192.255.25565,534
19478.193.0.0/1678.193.0.1 to 78.193.255.25478.193.255.25565,534
19578.194.0.0/1678.194.0.1 to 78.194.255.25478.194.255.25565,534
19678.195.0.0/1678.195.0.1 to 78.195.255.25478.195.255.25565,534
19778.196.0.0/1678.196.0.1 to 78.196.255.25478.196.255.25565,534
19878.197.0.0/1678.197.0.1 to 78.197.255.25478.197.255.25565,534
19978.198.0.0/1678.198.0.1 to 78.198.255.25478.198.255.25565,534
20078.199.0.0/1678.199.0.1 to 78.199.255.25478.199.255.25565,534
20178.200.0.0/1678.200.0.1 to 78.200.255.25478.200.255.25565,534
20278.201.0.0/1678.201.0.1 to 78.201.255.25478.201.255.25565,534
20378.202.0.0/1678.202.0.1 to 78.202.255.25478.202.255.25565,534
20478.203.0.0/1678.203.0.1 to 78.203.255.25478.203.255.25565,534
20578.204.0.0/1678.204.0.1 to 78.204.255.25478.204.255.25565,534
20678.205.0.0/1678.205.0.1 to 78.205.255.25478.205.255.25565,534
20778.206.0.0/1678.206.0.1 to 78.206.255.25478.206.255.25565,534
20878.207.0.0/1678.207.0.1 to 78.207.255.25478.207.255.25565,534
20978.208.0.0/1678.208.0.1 to 78.208.255.25478.208.255.25565,534
21078.209.0.0/1678.209.0.1 to 78.209.255.25478.209.255.25565,534
21178.210.0.0/1678.210.0.1 to 78.210.255.25478.210.255.25565,534
21278.211.0.0/1678.211.0.1 to 78.211.255.25478.211.255.25565,534
21378.212.0.0/1678.212.0.1 to 78.212.255.25478.212.255.25565,534
21478.213.0.0/1678.213.0.1 to 78.213.255.25478.213.255.25565,534
21578.214.0.0/1678.214.0.1 to 78.214.255.25478.214.255.25565,534
21678.215.0.0/1678.215.0.1 to 78.215.255.25478.215.255.25565,534
21778.216.0.0/1678.216.0.1 to 78.216.255.25478.216.255.25565,534
21878.217.0.0/1678.217.0.1 to 78.217.255.25478.217.255.25565,534
21978.218.0.0/1678.218.0.1 to 78.218.255.25478.218.255.25565,534
22078.219.0.0/1678.219.0.1 to 78.219.255.25478.219.255.25565,534
22178.220.0.0/1678.220.0.1 to 78.220.255.25478.220.255.25565,534
22278.221.0.0/1678.221.0.1 to 78.221.255.25478.221.255.25565,534
22378.222.0.0/1678.222.0.1 to 78.222.255.25478.222.255.25565,534
22478.223.0.0/1678.223.0.1 to 78.223.255.25478.223.255.25565,534
22578.224.0.0/1678.224.0.1 to 78.224.255.25478.224.255.25565,534
22678.225.0.0/1678.225.0.1 to 78.225.255.25478.225.255.25565,534
22778.226.0.0/1678.226.0.1 to 78.226.255.25478.226.255.25565,534
22878.227.0.0/1678.227.0.1 to 78.227.255.25478.227.255.25565,534
22978.228.0.0/1678.228.0.1 to 78.228.255.25478.228.255.25565,534
23078.229.0.0/1678.229.0.1 to 78.229.255.25478.229.255.25565,534
23178.230.0.0/1678.230.0.1 to 78.230.255.25478.230.255.25565,534
23278.231.0.0/1678.231.0.1 to 78.231.255.25478.231.255.25565,534
23378.232.0.0/1678.232.0.1 to 78.232.255.25478.232.255.25565,534
23478.233.0.0/1678.233.0.1 to 78.233.255.25478.233.255.25565,534
23578.234.0.0/1678.234.0.1 to 78.234.255.25478.234.255.25565,534
23678.235.0.0/1678.235.0.1 to 78.235.255.25478.235.255.25565,534
23778.236.0.0/1678.236.0.1 to 78.236.255.25478.236.255.25565,534
23878.237.0.0/1678.237.0.1 to 78.237.255.25478.237.255.25565,534
23978.238.0.0/1678.238.0.1 to 78.238.255.25478.238.255.25565,534
24078.239.0.0/1678.239.0.1 to 78.239.255.25478.239.255.25565,534
24178.240.0.0/1678.240.0.1 to 78.240.255.25478.240.255.25565,534
24278.241.0.0/1678.241.0.1 to 78.241.255.25478.241.255.25565,534
24378.242.0.0/1678.242.0.1 to 78.242.255.25478.242.255.25565,534
24478.243.0.0/1678.243.0.1 to 78.243.255.25478.243.255.25565,534
24578.244.0.0/1678.244.0.1 to 78.244.255.25478.244.255.25565,534
24678.245.0.0/1678.245.0.1 to 78.245.255.25478.245.255.25565,534
24778.246.0.0/1678.246.0.1 to 78.246.255.25478.246.255.25565,534
24878.247.0.0/1678.247.0.1 to 78.247.255.25478.247.255.25565,534
24978.248.0.0/1678.248.0.1 to 78.248.255.25478.248.255.25565,534
25078.249.0.0/1678.249.0.1 to 78.249.255.25478.249.255.25565,534
25178.250.0.0/1678.250.0.1 to 78.250.255.25478.250.255.25565,534
25278.251.0.0/1678.251.0.1 to 78.251.255.25478.251.255.25565,534
25378.252.0.0/1678.252.0.1 to 78.252.255.25478.252.255.25565,534
25478.253.0.0/1678.253.0.1 to 78.253.255.25478.253.255.25565,534
25578.254.0.0/1678.254.0.1 to 78.254.255.25478.254.255.25565,534
25678.255.0.0/1678.255.0.1 to 78.255.255.25478.255.255.25565,534

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.