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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.

Network49.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
49.0.0.0
Broadcast address
49.255.255.255
First usable
49.0.0.1
Last usable
49.255.255.254
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 31000000 · Integer 822083584 to 838860799
Reverse DNS zone
49.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110001..00000000.00000000.0000000049.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network00110001..00000000.00000000.0000000049.0.0.0
Broadcast00110001..11111111.11111111.1111111149.255.255.255
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)

49.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
149.0.0.0/1649.0.0.1 to 49.0.255.25449.0.255.25565,534
249.1.0.0/1649.1.0.1 to 49.1.255.25449.1.255.25565,534
349.2.0.0/1649.2.0.1 to 49.2.255.25449.2.255.25565,534
449.3.0.0/1649.3.0.1 to 49.3.255.25449.3.255.25565,534
549.4.0.0/1649.4.0.1 to 49.4.255.25449.4.255.25565,534
649.5.0.0/1649.5.0.1 to 49.5.255.25449.5.255.25565,534
749.6.0.0/1649.6.0.1 to 49.6.255.25449.6.255.25565,534
849.7.0.0/1649.7.0.1 to 49.7.255.25449.7.255.25565,534
949.8.0.0/1649.8.0.1 to 49.8.255.25449.8.255.25565,534
1049.9.0.0/1649.9.0.1 to 49.9.255.25449.9.255.25565,534
1149.10.0.0/1649.10.0.1 to 49.10.255.25449.10.255.25565,534
1249.11.0.0/1649.11.0.1 to 49.11.255.25449.11.255.25565,534
1349.12.0.0/1649.12.0.1 to 49.12.255.25449.12.255.25565,534
1449.13.0.0/1649.13.0.1 to 49.13.255.25449.13.255.25565,534
1549.14.0.0/1649.14.0.1 to 49.14.255.25449.14.255.25565,534
1649.15.0.0/1649.15.0.1 to 49.15.255.25449.15.255.25565,534
1749.16.0.0/1649.16.0.1 to 49.16.255.25449.16.255.25565,534
1849.17.0.0/1649.17.0.1 to 49.17.255.25449.17.255.25565,534
1949.18.0.0/1649.18.0.1 to 49.18.255.25449.18.255.25565,534
2049.19.0.0/1649.19.0.1 to 49.19.255.25449.19.255.25565,534
2149.20.0.0/1649.20.0.1 to 49.20.255.25449.20.255.25565,534
2249.21.0.0/1649.21.0.1 to 49.21.255.25449.21.255.25565,534
2349.22.0.0/1649.22.0.1 to 49.22.255.25449.22.255.25565,534
2449.23.0.0/1649.23.0.1 to 49.23.255.25449.23.255.25565,534
2549.24.0.0/1649.24.0.1 to 49.24.255.25449.24.255.25565,534
2649.25.0.0/1649.25.0.1 to 49.25.255.25449.25.255.25565,534
2749.26.0.0/1649.26.0.1 to 49.26.255.25449.26.255.25565,534
2849.27.0.0/1649.27.0.1 to 49.27.255.25449.27.255.25565,534
2949.28.0.0/1649.28.0.1 to 49.28.255.25449.28.255.25565,534
3049.29.0.0/1649.29.0.1 to 49.29.255.25449.29.255.25565,534
3149.30.0.0/1649.30.0.1 to 49.30.255.25449.30.255.25565,534
3249.31.0.0/1649.31.0.1 to 49.31.255.25449.31.255.25565,534
3349.32.0.0/1649.32.0.1 to 49.32.255.25449.32.255.25565,534
3449.33.0.0/1649.33.0.1 to 49.33.255.25449.33.255.25565,534
3549.34.0.0/1649.34.0.1 to 49.34.255.25449.34.255.25565,534
3649.35.0.0/1649.35.0.1 to 49.35.255.25449.35.255.25565,534
3749.36.0.0/1649.36.0.1 to 49.36.255.25449.36.255.25565,534
3849.37.0.0/1649.37.0.1 to 49.37.255.25449.37.255.25565,534
3949.38.0.0/1649.38.0.1 to 49.38.255.25449.38.255.25565,534
4049.39.0.0/1649.39.0.1 to 49.39.255.25449.39.255.25565,534
4149.40.0.0/1649.40.0.1 to 49.40.255.25449.40.255.25565,534
4249.41.0.0/1649.41.0.1 to 49.41.255.25449.41.255.25565,534
4349.42.0.0/1649.42.0.1 to 49.42.255.25449.42.255.25565,534
4449.43.0.0/1649.43.0.1 to 49.43.255.25449.43.255.25565,534
4549.44.0.0/1649.44.0.1 to 49.44.255.25449.44.255.25565,534
4649.45.0.0/1649.45.0.1 to 49.45.255.25449.45.255.25565,534
4749.46.0.0/1649.46.0.1 to 49.46.255.25449.46.255.25565,534
4849.47.0.0/1649.47.0.1 to 49.47.255.25449.47.255.25565,534
4949.48.0.0/1649.48.0.1 to 49.48.255.25449.48.255.25565,534
5049.49.0.0/1649.49.0.1 to 49.49.255.25449.49.255.25565,534
5149.50.0.0/1649.50.0.1 to 49.50.255.25449.50.255.25565,534
5249.51.0.0/1649.51.0.1 to 49.51.255.25449.51.255.25565,534
5349.52.0.0/1649.52.0.1 to 49.52.255.25449.52.255.25565,534
5449.53.0.0/1649.53.0.1 to 49.53.255.25449.53.255.25565,534
5549.54.0.0/1649.54.0.1 to 49.54.255.25449.54.255.25565,534
5649.55.0.0/1649.55.0.1 to 49.55.255.25449.55.255.25565,534
5749.56.0.0/1649.56.0.1 to 49.56.255.25449.56.255.25565,534
5849.57.0.0/1649.57.0.1 to 49.57.255.25449.57.255.25565,534
5949.58.0.0/1649.58.0.1 to 49.58.255.25449.58.255.25565,534
6049.59.0.0/1649.59.0.1 to 49.59.255.25449.59.255.25565,534
6149.60.0.0/1649.60.0.1 to 49.60.255.25449.60.255.25565,534
6249.61.0.0/1649.61.0.1 to 49.61.255.25449.61.255.25565,534
6349.62.0.0/1649.62.0.1 to 49.62.255.25449.62.255.25565,534
6449.63.0.0/1649.63.0.1 to 49.63.255.25449.63.255.25565,534
6549.64.0.0/1649.64.0.1 to 49.64.255.25449.64.255.25565,534
6649.65.0.0/1649.65.0.1 to 49.65.255.25449.65.255.25565,534
6749.66.0.0/1649.66.0.1 to 49.66.255.25449.66.255.25565,534
6849.67.0.0/1649.67.0.1 to 49.67.255.25449.67.255.25565,534
6949.68.0.0/1649.68.0.1 to 49.68.255.25449.68.255.25565,534
7049.69.0.0/1649.69.0.1 to 49.69.255.25449.69.255.25565,534
7149.70.0.0/1649.70.0.1 to 49.70.255.25449.70.255.25565,534
7249.71.0.0/1649.71.0.1 to 49.71.255.25449.71.255.25565,534
7349.72.0.0/1649.72.0.1 to 49.72.255.25449.72.255.25565,534
7449.73.0.0/1649.73.0.1 to 49.73.255.25449.73.255.25565,534
7549.74.0.0/1649.74.0.1 to 49.74.255.25449.74.255.25565,534
7649.75.0.0/1649.75.0.1 to 49.75.255.25449.75.255.25565,534
7749.76.0.0/1649.76.0.1 to 49.76.255.25449.76.255.25565,534
7849.77.0.0/1649.77.0.1 to 49.77.255.25449.77.255.25565,534
7949.78.0.0/1649.78.0.1 to 49.78.255.25449.78.255.25565,534
8049.79.0.0/1649.79.0.1 to 49.79.255.25449.79.255.25565,534
8149.80.0.0/1649.80.0.1 to 49.80.255.25449.80.255.25565,534
8249.81.0.0/1649.81.0.1 to 49.81.255.25449.81.255.25565,534
8349.82.0.0/1649.82.0.1 to 49.82.255.25449.82.255.25565,534
8449.83.0.0/1649.83.0.1 to 49.83.255.25449.83.255.25565,534
8549.84.0.0/1649.84.0.1 to 49.84.255.25449.84.255.25565,534
8649.85.0.0/1649.85.0.1 to 49.85.255.25449.85.255.25565,534
8749.86.0.0/1649.86.0.1 to 49.86.255.25449.86.255.25565,534
8849.87.0.0/1649.87.0.1 to 49.87.255.25449.87.255.25565,534
8949.88.0.0/1649.88.0.1 to 49.88.255.25449.88.255.25565,534
9049.89.0.0/1649.89.0.1 to 49.89.255.25449.89.255.25565,534
9149.90.0.0/1649.90.0.1 to 49.90.255.25449.90.255.25565,534
9249.91.0.0/1649.91.0.1 to 49.91.255.25449.91.255.25565,534
9349.92.0.0/1649.92.0.1 to 49.92.255.25449.92.255.25565,534
9449.93.0.0/1649.93.0.1 to 49.93.255.25449.93.255.25565,534
9549.94.0.0/1649.94.0.1 to 49.94.255.25449.94.255.25565,534
9649.95.0.0/1649.95.0.1 to 49.95.255.25449.95.255.25565,534
9749.96.0.0/1649.96.0.1 to 49.96.255.25449.96.255.25565,534
9849.97.0.0/1649.97.0.1 to 49.97.255.25449.97.255.25565,534
9949.98.0.0/1649.98.0.1 to 49.98.255.25449.98.255.25565,534
10049.99.0.0/1649.99.0.1 to 49.99.255.25449.99.255.25565,534
10149.100.0.0/1649.100.0.1 to 49.100.255.25449.100.255.25565,534
10249.101.0.0/1649.101.0.1 to 49.101.255.25449.101.255.25565,534
10349.102.0.0/1649.102.0.1 to 49.102.255.25449.102.255.25565,534
10449.103.0.0/1649.103.0.1 to 49.103.255.25449.103.255.25565,534
10549.104.0.0/1649.104.0.1 to 49.104.255.25449.104.255.25565,534
10649.105.0.0/1649.105.0.1 to 49.105.255.25449.105.255.25565,534
10749.106.0.0/1649.106.0.1 to 49.106.255.25449.106.255.25565,534
10849.107.0.0/1649.107.0.1 to 49.107.255.25449.107.255.25565,534
10949.108.0.0/1649.108.0.1 to 49.108.255.25449.108.255.25565,534
11049.109.0.0/1649.109.0.1 to 49.109.255.25449.109.255.25565,534
11149.110.0.0/1649.110.0.1 to 49.110.255.25449.110.255.25565,534
11249.111.0.0/1649.111.0.1 to 49.111.255.25449.111.255.25565,534
11349.112.0.0/1649.112.0.1 to 49.112.255.25449.112.255.25565,534
11449.113.0.0/1649.113.0.1 to 49.113.255.25449.113.255.25565,534
11549.114.0.0/1649.114.0.1 to 49.114.255.25449.114.255.25565,534
11649.115.0.0/1649.115.0.1 to 49.115.255.25449.115.255.25565,534
11749.116.0.0/1649.116.0.1 to 49.116.255.25449.116.255.25565,534
11849.117.0.0/1649.117.0.1 to 49.117.255.25449.117.255.25565,534
11949.118.0.0/1649.118.0.1 to 49.118.255.25449.118.255.25565,534
12049.119.0.0/1649.119.0.1 to 49.119.255.25449.119.255.25565,534
12149.120.0.0/1649.120.0.1 to 49.120.255.25449.120.255.25565,534
12249.121.0.0/1649.121.0.1 to 49.121.255.25449.121.255.25565,534
12349.122.0.0/1649.122.0.1 to 49.122.255.25449.122.255.25565,534
12449.123.0.0/1649.123.0.1 to 49.123.255.25449.123.255.25565,534
12549.124.0.0/1649.124.0.1 to 49.124.255.25449.124.255.25565,534
12649.125.0.0/1649.125.0.1 to 49.125.255.25449.125.255.25565,534
12749.126.0.0/1649.126.0.1 to 49.126.255.25449.126.255.25565,534
12849.127.0.0/1649.127.0.1 to 49.127.255.25449.127.255.25565,534
12949.128.0.0/1649.128.0.1 to 49.128.255.25449.128.255.25565,534
13049.129.0.0/1649.129.0.1 to 49.129.255.25449.129.255.25565,534
13149.130.0.0/1649.130.0.1 to 49.130.255.25449.130.255.25565,534
13249.131.0.0/1649.131.0.1 to 49.131.255.25449.131.255.25565,534
13349.132.0.0/1649.132.0.1 to 49.132.255.25449.132.255.25565,534
13449.133.0.0/1649.133.0.1 to 49.133.255.25449.133.255.25565,534
13549.134.0.0/1649.134.0.1 to 49.134.255.25449.134.255.25565,534
13649.135.0.0/1649.135.0.1 to 49.135.255.25449.135.255.25565,534
13749.136.0.0/1649.136.0.1 to 49.136.255.25449.136.255.25565,534
13849.137.0.0/1649.137.0.1 to 49.137.255.25449.137.255.25565,534
13949.138.0.0/1649.138.0.1 to 49.138.255.25449.138.255.25565,534
14049.139.0.0/1649.139.0.1 to 49.139.255.25449.139.255.25565,534
14149.140.0.0/1649.140.0.1 to 49.140.255.25449.140.255.25565,534
14249.141.0.0/1649.141.0.1 to 49.141.255.25449.141.255.25565,534
14349.142.0.0/1649.142.0.1 to 49.142.255.25449.142.255.25565,534
14449.143.0.0/1649.143.0.1 to 49.143.255.25449.143.255.25565,534
14549.144.0.0/1649.144.0.1 to 49.144.255.25449.144.255.25565,534
14649.145.0.0/1649.145.0.1 to 49.145.255.25449.145.255.25565,534
14749.146.0.0/1649.146.0.1 to 49.146.255.25449.146.255.25565,534
14849.147.0.0/1649.147.0.1 to 49.147.255.25449.147.255.25565,534
14949.148.0.0/1649.148.0.1 to 49.148.255.25449.148.255.25565,534
15049.149.0.0/1649.149.0.1 to 49.149.255.25449.149.255.25565,534
15149.150.0.0/1649.150.0.1 to 49.150.255.25449.150.255.25565,534
15249.151.0.0/1649.151.0.1 to 49.151.255.25449.151.255.25565,534
15349.152.0.0/1649.152.0.1 to 49.152.255.25449.152.255.25565,534
15449.153.0.0/1649.153.0.1 to 49.153.255.25449.153.255.25565,534
15549.154.0.0/1649.154.0.1 to 49.154.255.25449.154.255.25565,534
15649.155.0.0/1649.155.0.1 to 49.155.255.25449.155.255.25565,534
15749.156.0.0/1649.156.0.1 to 49.156.255.25449.156.255.25565,534
15849.157.0.0/1649.157.0.1 to 49.157.255.25449.157.255.25565,534
15949.158.0.0/1649.158.0.1 to 49.158.255.25449.158.255.25565,534
16049.159.0.0/1649.159.0.1 to 49.159.255.25449.159.255.25565,534
16149.160.0.0/1649.160.0.1 to 49.160.255.25449.160.255.25565,534
16249.161.0.0/1649.161.0.1 to 49.161.255.25449.161.255.25565,534
16349.162.0.0/1649.162.0.1 to 49.162.255.25449.162.255.25565,534
16449.163.0.0/1649.163.0.1 to 49.163.255.25449.163.255.25565,534
16549.164.0.0/1649.164.0.1 to 49.164.255.25449.164.255.25565,534
16649.165.0.0/1649.165.0.1 to 49.165.255.25449.165.255.25565,534
16749.166.0.0/1649.166.0.1 to 49.166.255.25449.166.255.25565,534
16849.167.0.0/1649.167.0.1 to 49.167.255.25449.167.255.25565,534
16949.168.0.0/1649.168.0.1 to 49.168.255.25449.168.255.25565,534
17049.169.0.0/1649.169.0.1 to 49.169.255.25449.169.255.25565,534
17149.170.0.0/1649.170.0.1 to 49.170.255.25449.170.255.25565,534
17249.171.0.0/1649.171.0.1 to 49.171.255.25449.171.255.25565,534
17349.172.0.0/1649.172.0.1 to 49.172.255.25449.172.255.25565,534
17449.173.0.0/1649.173.0.1 to 49.173.255.25449.173.255.25565,534
17549.174.0.0/1649.174.0.1 to 49.174.255.25449.174.255.25565,534
17649.175.0.0/1649.175.0.1 to 49.175.255.25449.175.255.25565,534
17749.176.0.0/1649.176.0.1 to 49.176.255.25449.176.255.25565,534
17849.177.0.0/1649.177.0.1 to 49.177.255.25449.177.255.25565,534
17949.178.0.0/1649.178.0.1 to 49.178.255.25449.178.255.25565,534
18049.179.0.0/1649.179.0.1 to 49.179.255.25449.179.255.25565,534
18149.180.0.0/1649.180.0.1 to 49.180.255.25449.180.255.25565,534
18249.181.0.0/1649.181.0.1 to 49.181.255.25449.181.255.25565,534
18349.182.0.0/1649.182.0.1 to 49.182.255.25449.182.255.25565,534
18449.183.0.0/1649.183.0.1 to 49.183.255.25449.183.255.25565,534
18549.184.0.0/1649.184.0.1 to 49.184.255.25449.184.255.25565,534
18649.185.0.0/1649.185.0.1 to 49.185.255.25449.185.255.25565,534
18749.186.0.0/1649.186.0.1 to 49.186.255.25449.186.255.25565,534
18849.187.0.0/1649.187.0.1 to 49.187.255.25449.187.255.25565,534
18949.188.0.0/1649.188.0.1 to 49.188.255.25449.188.255.25565,534
19049.189.0.0/1649.189.0.1 to 49.189.255.25449.189.255.25565,534
19149.190.0.0/1649.190.0.1 to 49.190.255.25449.190.255.25565,534
19249.191.0.0/1649.191.0.1 to 49.191.255.25449.191.255.25565,534
19349.192.0.0/1649.192.0.1 to 49.192.255.25449.192.255.25565,534
19449.193.0.0/1649.193.0.1 to 49.193.255.25449.193.255.25565,534
19549.194.0.0/1649.194.0.1 to 49.194.255.25449.194.255.25565,534
19649.195.0.0/1649.195.0.1 to 49.195.255.25449.195.255.25565,534
19749.196.0.0/1649.196.0.1 to 49.196.255.25449.196.255.25565,534
19849.197.0.0/1649.197.0.1 to 49.197.255.25449.197.255.25565,534
19949.198.0.0/1649.198.0.1 to 49.198.255.25449.198.255.25565,534
20049.199.0.0/1649.199.0.1 to 49.199.255.25449.199.255.25565,534
20149.200.0.0/1649.200.0.1 to 49.200.255.25449.200.255.25565,534
20249.201.0.0/1649.201.0.1 to 49.201.255.25449.201.255.25565,534
20349.202.0.0/1649.202.0.1 to 49.202.255.25449.202.255.25565,534
20449.203.0.0/1649.203.0.1 to 49.203.255.25449.203.255.25565,534
20549.204.0.0/1649.204.0.1 to 49.204.255.25449.204.255.25565,534
20649.205.0.0/1649.205.0.1 to 49.205.255.25449.205.255.25565,534
20749.206.0.0/1649.206.0.1 to 49.206.255.25449.206.255.25565,534
20849.207.0.0/1649.207.0.1 to 49.207.255.25449.207.255.25565,534
20949.208.0.0/1649.208.0.1 to 49.208.255.25449.208.255.25565,534
21049.209.0.0/1649.209.0.1 to 49.209.255.25449.209.255.25565,534
21149.210.0.0/1649.210.0.1 to 49.210.255.25449.210.255.25565,534
21249.211.0.0/1649.211.0.1 to 49.211.255.25449.211.255.25565,534
21349.212.0.0/1649.212.0.1 to 49.212.255.25449.212.255.25565,534
21449.213.0.0/1649.213.0.1 to 49.213.255.25449.213.255.25565,534
21549.214.0.0/1649.214.0.1 to 49.214.255.25449.214.255.25565,534
21649.215.0.0/1649.215.0.1 to 49.215.255.25449.215.255.25565,534
21749.216.0.0/1649.216.0.1 to 49.216.255.25449.216.255.25565,534
21849.217.0.0/1649.217.0.1 to 49.217.255.25449.217.255.25565,534
21949.218.0.0/1649.218.0.1 to 49.218.255.25449.218.255.25565,534
22049.219.0.0/1649.219.0.1 to 49.219.255.25449.219.255.25565,534
22149.220.0.0/1649.220.0.1 to 49.220.255.25449.220.255.25565,534
22249.221.0.0/1649.221.0.1 to 49.221.255.25449.221.255.25565,534
22349.222.0.0/1649.222.0.1 to 49.222.255.25449.222.255.25565,534
22449.223.0.0/1649.223.0.1 to 49.223.255.25449.223.255.25565,534
22549.224.0.0/1649.224.0.1 to 49.224.255.25449.224.255.25565,534
22649.225.0.0/1649.225.0.1 to 49.225.255.25449.225.255.25565,534
22749.226.0.0/1649.226.0.1 to 49.226.255.25449.226.255.25565,534
22849.227.0.0/1649.227.0.1 to 49.227.255.25449.227.255.25565,534
22949.228.0.0/1649.228.0.1 to 49.228.255.25449.228.255.25565,534
23049.229.0.0/1649.229.0.1 to 49.229.255.25449.229.255.25565,534
23149.230.0.0/1649.230.0.1 to 49.230.255.25449.230.255.25565,534
23249.231.0.0/1649.231.0.1 to 49.231.255.25449.231.255.25565,534
23349.232.0.0/1649.232.0.1 to 49.232.255.25449.232.255.25565,534
23449.233.0.0/1649.233.0.1 to 49.233.255.25449.233.255.25565,534
23549.234.0.0/1649.234.0.1 to 49.234.255.25449.234.255.25565,534
23649.235.0.0/1649.235.0.1 to 49.235.255.25449.235.255.25565,534
23749.236.0.0/1649.236.0.1 to 49.236.255.25449.236.255.25565,534
23849.237.0.0/1649.237.0.1 to 49.237.255.25449.237.255.25565,534
23949.238.0.0/1649.238.0.1 to 49.238.255.25449.238.255.25565,534
24049.239.0.0/1649.239.0.1 to 49.239.255.25449.239.255.25565,534
24149.240.0.0/1649.240.0.1 to 49.240.255.25449.240.255.25565,534
24249.241.0.0/1649.241.0.1 to 49.241.255.25449.241.255.25565,534
24349.242.0.0/1649.242.0.1 to 49.242.255.25449.242.255.25565,534
24449.243.0.0/1649.243.0.1 to 49.243.255.25449.243.255.25565,534
24549.244.0.0/1649.244.0.1 to 49.244.255.25449.244.255.25565,534
24649.245.0.0/1649.245.0.1 to 49.245.255.25449.245.255.25565,534
24749.246.0.0/1649.246.0.1 to 49.246.255.25449.246.255.25565,534
24849.247.0.0/1649.247.0.1 to 49.247.255.25449.247.255.25565,534
24949.248.0.0/1649.248.0.1 to 49.248.255.25449.248.255.25565,534
25049.249.0.0/1649.249.0.1 to 49.249.255.25449.249.255.25565,534
25149.250.0.0/1649.250.0.1 to 49.250.255.25449.250.255.25565,534
25249.251.0.0/1649.251.0.1 to 49.251.255.25449.251.255.25565,534
25349.252.0.0/1649.252.0.1 to 49.252.255.25449.252.255.25565,534
25449.253.0.0/1649.253.0.1 to 49.253.255.25449.253.255.25565,534
25549.254.0.0/1649.254.0.1 to 49.254.255.25449.254.255.25565,534
25649.255.0.0/1649.255.0.1 to 49.255.255.25449.255.255.25565,534

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.