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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.

Network49.0.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
49.0.0.0
Broadcast address
49.63.255.255
First usable
49.0.0.1
Last usable
49.63.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Public public
Old class
A (default /8)
As numbers
Hex 31000000 · Integer 822083584 to 826277887
Reverse DNS zones
0.49.in-addr.arpa
1.49.in-addr.arpa
2.49.in-addr.arpa
3.49.in-addr.arpa
4.49.in-addr.arpa
5.49.in-addr.arpa
6.49.in-addr.arpa
7.49.in-addr.arpa
8.49.in-addr.arpa
9.49.in-addr.arpa
10.49.in-addr.arpa
11.49.in-addr.arpa
12.49.in-addr.arpa
13.49.in-addr.arpa
14.49.in-addr.arpa
15.49.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110001.00000000.00000000.0000000049.0.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00110001.00000000.00000000.0000000049.0.0.0
Broadcast00110001.00111111.11111111.1111111149.63.255.255
Split into smaller subnets/22
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

49.0.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
149.0.0.0/2249.0.0.1 to 49.0.3.25449.0.3.2551,022
249.0.4.0/2249.0.4.1 to 49.0.7.25449.0.7.2551,022
349.0.8.0/2249.0.8.1 to 49.0.11.25449.0.11.2551,022
449.0.12.0/2249.0.12.1 to 49.0.15.25449.0.15.2551,022
549.0.16.0/2249.0.16.1 to 49.0.19.25449.0.19.2551,022
649.0.20.0/2249.0.20.1 to 49.0.23.25449.0.23.2551,022
749.0.24.0/2249.0.24.1 to 49.0.27.25449.0.27.2551,022
849.0.28.0/2249.0.28.1 to 49.0.31.25449.0.31.2551,022
949.0.32.0/2249.0.32.1 to 49.0.35.25449.0.35.2551,022
1049.0.36.0/2249.0.36.1 to 49.0.39.25449.0.39.2551,022
1149.0.40.0/2249.0.40.1 to 49.0.43.25449.0.43.2551,022
1249.0.44.0/2249.0.44.1 to 49.0.47.25449.0.47.2551,022
1349.0.48.0/2249.0.48.1 to 49.0.51.25449.0.51.2551,022
1449.0.52.0/2249.0.52.1 to 49.0.55.25449.0.55.2551,022
1549.0.56.0/2249.0.56.1 to 49.0.59.25449.0.59.2551,022
1649.0.60.0/2249.0.60.1 to 49.0.63.25449.0.63.2551,022
1749.0.64.0/2249.0.64.1 to 49.0.67.25449.0.67.2551,022
1849.0.68.0/2249.0.68.1 to 49.0.71.25449.0.71.2551,022
1949.0.72.0/2249.0.72.1 to 49.0.75.25449.0.75.2551,022
2049.0.76.0/2249.0.76.1 to 49.0.79.25449.0.79.2551,022
2149.0.80.0/2249.0.80.1 to 49.0.83.25449.0.83.2551,022
2249.0.84.0/2249.0.84.1 to 49.0.87.25449.0.87.2551,022
2349.0.88.0/2249.0.88.1 to 49.0.91.25449.0.91.2551,022
2449.0.92.0/2249.0.92.1 to 49.0.95.25449.0.95.2551,022
2549.0.96.0/2249.0.96.1 to 49.0.99.25449.0.99.2551,022
2649.0.100.0/2249.0.100.1 to 49.0.103.25449.0.103.2551,022
2749.0.104.0/2249.0.104.1 to 49.0.107.25449.0.107.2551,022
2849.0.108.0/2249.0.108.1 to 49.0.111.25449.0.111.2551,022
2949.0.112.0/2249.0.112.1 to 49.0.115.25449.0.115.2551,022
3049.0.116.0/2249.0.116.1 to 49.0.119.25449.0.119.2551,022
3149.0.120.0/2249.0.120.1 to 49.0.123.25449.0.123.2551,022
3249.0.124.0/2249.0.124.1 to 49.0.127.25449.0.127.2551,022
3349.0.128.0/2249.0.128.1 to 49.0.131.25449.0.131.2551,022
3449.0.132.0/2249.0.132.1 to 49.0.135.25449.0.135.2551,022
3549.0.136.0/2249.0.136.1 to 49.0.139.25449.0.139.2551,022
3649.0.140.0/2249.0.140.1 to 49.0.143.25449.0.143.2551,022
3749.0.144.0/2249.0.144.1 to 49.0.147.25449.0.147.2551,022
3849.0.148.0/2249.0.148.1 to 49.0.151.25449.0.151.2551,022
3949.0.152.0/2249.0.152.1 to 49.0.155.25449.0.155.2551,022
4049.0.156.0/2249.0.156.1 to 49.0.159.25449.0.159.2551,022
4149.0.160.0/2249.0.160.1 to 49.0.163.25449.0.163.2551,022
4249.0.164.0/2249.0.164.1 to 49.0.167.25449.0.167.2551,022
4349.0.168.0/2249.0.168.1 to 49.0.171.25449.0.171.2551,022
4449.0.172.0/2249.0.172.1 to 49.0.175.25449.0.175.2551,022
4549.0.176.0/2249.0.176.1 to 49.0.179.25449.0.179.2551,022
4649.0.180.0/2249.0.180.1 to 49.0.183.25449.0.183.2551,022
4749.0.184.0/2249.0.184.1 to 49.0.187.25449.0.187.2551,022
4849.0.188.0/2249.0.188.1 to 49.0.191.25449.0.191.2551,022
4949.0.192.0/2249.0.192.1 to 49.0.195.25449.0.195.2551,022
5049.0.196.0/2249.0.196.1 to 49.0.199.25449.0.199.2551,022
5149.0.200.0/2249.0.200.1 to 49.0.203.25449.0.203.2551,022
5249.0.204.0/2249.0.204.1 to 49.0.207.25449.0.207.2551,022
5349.0.208.0/2249.0.208.1 to 49.0.211.25449.0.211.2551,022
5449.0.212.0/2249.0.212.1 to 49.0.215.25449.0.215.2551,022
5549.0.216.0/2249.0.216.1 to 49.0.219.25449.0.219.2551,022
5649.0.220.0/2249.0.220.1 to 49.0.223.25449.0.223.2551,022
5749.0.224.0/2249.0.224.1 to 49.0.227.25449.0.227.2551,022
5849.0.228.0/2249.0.228.1 to 49.0.231.25449.0.231.2551,022
5949.0.232.0/2249.0.232.1 to 49.0.235.25449.0.235.2551,022
6049.0.236.0/2249.0.236.1 to 49.0.239.25449.0.239.2551,022
6149.0.240.0/2249.0.240.1 to 49.0.243.25449.0.243.2551,022
6249.0.244.0/2249.0.244.1 to 49.0.247.25449.0.247.2551,022
6349.0.248.0/2249.0.248.1 to 49.0.251.25449.0.251.2551,022
6449.0.252.0/2249.0.252.1 to 49.0.255.25449.0.255.2551,022
6549.1.0.0/2249.1.0.1 to 49.1.3.25449.1.3.2551,022
6649.1.4.0/2249.1.4.1 to 49.1.7.25449.1.7.2551,022
6749.1.8.0/2249.1.8.1 to 49.1.11.25449.1.11.2551,022
6849.1.12.0/2249.1.12.1 to 49.1.15.25449.1.15.2551,022
6949.1.16.0/2249.1.16.1 to 49.1.19.25449.1.19.2551,022
7049.1.20.0/2249.1.20.1 to 49.1.23.25449.1.23.2551,022
7149.1.24.0/2249.1.24.1 to 49.1.27.25449.1.27.2551,022
7249.1.28.0/2249.1.28.1 to 49.1.31.25449.1.31.2551,022
7349.1.32.0/2249.1.32.1 to 49.1.35.25449.1.35.2551,022
7449.1.36.0/2249.1.36.1 to 49.1.39.25449.1.39.2551,022
7549.1.40.0/2249.1.40.1 to 49.1.43.25449.1.43.2551,022
7649.1.44.0/2249.1.44.1 to 49.1.47.25449.1.47.2551,022
7749.1.48.0/2249.1.48.1 to 49.1.51.25449.1.51.2551,022
7849.1.52.0/2249.1.52.1 to 49.1.55.25449.1.55.2551,022
7949.1.56.0/2249.1.56.1 to 49.1.59.25449.1.59.2551,022
8049.1.60.0/2249.1.60.1 to 49.1.63.25449.1.63.2551,022
8149.1.64.0/2249.1.64.1 to 49.1.67.25449.1.67.2551,022
8249.1.68.0/2249.1.68.1 to 49.1.71.25449.1.71.2551,022
8349.1.72.0/2249.1.72.1 to 49.1.75.25449.1.75.2551,022
8449.1.76.0/2249.1.76.1 to 49.1.79.25449.1.79.2551,022
8549.1.80.0/2249.1.80.1 to 49.1.83.25449.1.83.2551,022
8649.1.84.0/2249.1.84.1 to 49.1.87.25449.1.87.2551,022
8749.1.88.0/2249.1.88.1 to 49.1.91.25449.1.91.2551,022
8849.1.92.0/2249.1.92.1 to 49.1.95.25449.1.95.2551,022
8949.1.96.0/2249.1.96.1 to 49.1.99.25449.1.99.2551,022
9049.1.100.0/2249.1.100.1 to 49.1.103.25449.1.103.2551,022
9149.1.104.0/2249.1.104.1 to 49.1.107.25449.1.107.2551,022
9249.1.108.0/2249.1.108.1 to 49.1.111.25449.1.111.2551,022
9349.1.112.0/2249.1.112.1 to 49.1.115.25449.1.115.2551,022
9449.1.116.0/2249.1.116.1 to 49.1.119.25449.1.119.2551,022
9549.1.120.0/2249.1.120.1 to 49.1.123.25449.1.123.2551,022
9649.1.124.0/2249.1.124.1 to 49.1.127.25449.1.127.2551,022
9749.1.128.0/2249.1.128.1 to 49.1.131.25449.1.131.2551,022
9849.1.132.0/2249.1.132.1 to 49.1.135.25449.1.135.2551,022
9949.1.136.0/2249.1.136.1 to 49.1.139.25449.1.139.2551,022
10049.1.140.0/2249.1.140.1 to 49.1.143.25449.1.143.2551,022
10149.1.144.0/2249.1.144.1 to 49.1.147.25449.1.147.2551,022
10249.1.148.0/2249.1.148.1 to 49.1.151.25449.1.151.2551,022
10349.1.152.0/2249.1.152.1 to 49.1.155.25449.1.155.2551,022
10449.1.156.0/2249.1.156.1 to 49.1.159.25449.1.159.2551,022
10549.1.160.0/2249.1.160.1 to 49.1.163.25449.1.163.2551,022
10649.1.164.0/2249.1.164.1 to 49.1.167.25449.1.167.2551,022
10749.1.168.0/2249.1.168.1 to 49.1.171.25449.1.171.2551,022
10849.1.172.0/2249.1.172.1 to 49.1.175.25449.1.175.2551,022
10949.1.176.0/2249.1.176.1 to 49.1.179.25449.1.179.2551,022
11049.1.180.0/2249.1.180.1 to 49.1.183.25449.1.183.2551,022
11149.1.184.0/2249.1.184.1 to 49.1.187.25449.1.187.2551,022
11249.1.188.0/2249.1.188.1 to 49.1.191.25449.1.191.2551,022
11349.1.192.0/2249.1.192.1 to 49.1.195.25449.1.195.2551,022
11449.1.196.0/2249.1.196.1 to 49.1.199.25449.1.199.2551,022
11549.1.200.0/2249.1.200.1 to 49.1.203.25449.1.203.2551,022
11649.1.204.0/2249.1.204.1 to 49.1.207.25449.1.207.2551,022
11749.1.208.0/2249.1.208.1 to 49.1.211.25449.1.211.2551,022
11849.1.212.0/2249.1.212.1 to 49.1.215.25449.1.215.2551,022
11949.1.216.0/2249.1.216.1 to 49.1.219.25449.1.219.2551,022
12049.1.220.0/2249.1.220.1 to 49.1.223.25449.1.223.2551,022
12149.1.224.0/2249.1.224.1 to 49.1.227.25449.1.227.2551,022
12249.1.228.0/2249.1.228.1 to 49.1.231.25449.1.231.2551,022
12349.1.232.0/2249.1.232.1 to 49.1.235.25449.1.235.2551,022
12449.1.236.0/2249.1.236.1 to 49.1.239.25449.1.239.2551,022
12549.1.240.0/2249.1.240.1 to 49.1.243.25449.1.243.2551,022
12649.1.244.0/2249.1.244.1 to 49.1.247.25449.1.247.2551,022
12749.1.248.0/2249.1.248.1 to 49.1.251.25449.1.251.2551,022
12849.1.252.0/2249.1.252.1 to 49.1.255.25449.1.255.2551,022
12949.2.0.0/2249.2.0.1 to 49.2.3.25449.2.3.2551,022
13049.2.4.0/2249.2.4.1 to 49.2.7.25449.2.7.2551,022
13149.2.8.0/2249.2.8.1 to 49.2.11.25449.2.11.2551,022
13249.2.12.0/2249.2.12.1 to 49.2.15.25449.2.15.2551,022
13349.2.16.0/2249.2.16.1 to 49.2.19.25449.2.19.2551,022
13449.2.20.0/2249.2.20.1 to 49.2.23.25449.2.23.2551,022
13549.2.24.0/2249.2.24.1 to 49.2.27.25449.2.27.2551,022
13649.2.28.0/2249.2.28.1 to 49.2.31.25449.2.31.2551,022
13749.2.32.0/2249.2.32.1 to 49.2.35.25449.2.35.2551,022
13849.2.36.0/2249.2.36.1 to 49.2.39.25449.2.39.2551,022
13949.2.40.0/2249.2.40.1 to 49.2.43.25449.2.43.2551,022
14049.2.44.0/2249.2.44.1 to 49.2.47.25449.2.47.2551,022
14149.2.48.0/2249.2.48.1 to 49.2.51.25449.2.51.2551,022
14249.2.52.0/2249.2.52.1 to 49.2.55.25449.2.55.2551,022
14349.2.56.0/2249.2.56.1 to 49.2.59.25449.2.59.2551,022
14449.2.60.0/2249.2.60.1 to 49.2.63.25449.2.63.2551,022
14549.2.64.0/2249.2.64.1 to 49.2.67.25449.2.67.2551,022
14649.2.68.0/2249.2.68.1 to 49.2.71.25449.2.71.2551,022
14749.2.72.0/2249.2.72.1 to 49.2.75.25449.2.75.2551,022
14849.2.76.0/2249.2.76.1 to 49.2.79.25449.2.79.2551,022
14949.2.80.0/2249.2.80.1 to 49.2.83.25449.2.83.2551,022
15049.2.84.0/2249.2.84.1 to 49.2.87.25449.2.87.2551,022
15149.2.88.0/2249.2.88.1 to 49.2.91.25449.2.91.2551,022
15249.2.92.0/2249.2.92.1 to 49.2.95.25449.2.95.2551,022
15349.2.96.0/2249.2.96.1 to 49.2.99.25449.2.99.2551,022
15449.2.100.0/2249.2.100.1 to 49.2.103.25449.2.103.2551,022
15549.2.104.0/2249.2.104.1 to 49.2.107.25449.2.107.2551,022
15649.2.108.0/2249.2.108.1 to 49.2.111.25449.2.111.2551,022
15749.2.112.0/2249.2.112.1 to 49.2.115.25449.2.115.2551,022
15849.2.116.0/2249.2.116.1 to 49.2.119.25449.2.119.2551,022
15949.2.120.0/2249.2.120.1 to 49.2.123.25449.2.123.2551,022
16049.2.124.0/2249.2.124.1 to 49.2.127.25449.2.127.2551,022
16149.2.128.0/2249.2.128.1 to 49.2.131.25449.2.131.2551,022
16249.2.132.0/2249.2.132.1 to 49.2.135.25449.2.135.2551,022
16349.2.136.0/2249.2.136.1 to 49.2.139.25449.2.139.2551,022
16449.2.140.0/2249.2.140.1 to 49.2.143.25449.2.143.2551,022
16549.2.144.0/2249.2.144.1 to 49.2.147.25449.2.147.2551,022
16649.2.148.0/2249.2.148.1 to 49.2.151.25449.2.151.2551,022
16749.2.152.0/2249.2.152.1 to 49.2.155.25449.2.155.2551,022
16849.2.156.0/2249.2.156.1 to 49.2.159.25449.2.159.2551,022
16949.2.160.0/2249.2.160.1 to 49.2.163.25449.2.163.2551,022
17049.2.164.0/2249.2.164.1 to 49.2.167.25449.2.167.2551,022
17149.2.168.0/2249.2.168.1 to 49.2.171.25449.2.171.2551,022
17249.2.172.0/2249.2.172.1 to 49.2.175.25449.2.175.2551,022
17349.2.176.0/2249.2.176.1 to 49.2.179.25449.2.179.2551,022
17449.2.180.0/2249.2.180.1 to 49.2.183.25449.2.183.2551,022
17549.2.184.0/2249.2.184.1 to 49.2.187.25449.2.187.2551,022
17649.2.188.0/2249.2.188.1 to 49.2.191.25449.2.191.2551,022
17749.2.192.0/2249.2.192.1 to 49.2.195.25449.2.195.2551,022
17849.2.196.0/2249.2.196.1 to 49.2.199.25449.2.199.2551,022
17949.2.200.0/2249.2.200.1 to 49.2.203.25449.2.203.2551,022
18049.2.204.0/2249.2.204.1 to 49.2.207.25449.2.207.2551,022
18149.2.208.0/2249.2.208.1 to 49.2.211.25449.2.211.2551,022
18249.2.212.0/2249.2.212.1 to 49.2.215.25449.2.215.2551,022
18349.2.216.0/2249.2.216.1 to 49.2.219.25449.2.219.2551,022
18449.2.220.0/2249.2.220.1 to 49.2.223.25449.2.223.2551,022
18549.2.224.0/2249.2.224.1 to 49.2.227.25449.2.227.2551,022
18649.2.228.0/2249.2.228.1 to 49.2.231.25449.2.231.2551,022
18749.2.232.0/2249.2.232.1 to 49.2.235.25449.2.235.2551,022
18849.2.236.0/2249.2.236.1 to 49.2.239.25449.2.239.2551,022
18949.2.240.0/2249.2.240.1 to 49.2.243.25449.2.243.2551,022
19049.2.244.0/2249.2.244.1 to 49.2.247.25449.2.247.2551,022
19149.2.248.0/2249.2.248.1 to 49.2.251.25449.2.251.2551,022
19249.2.252.0/2249.2.252.1 to 49.2.255.25449.2.255.2551,022
19349.3.0.0/2249.3.0.1 to 49.3.3.25449.3.3.2551,022
19449.3.4.0/2249.3.4.1 to 49.3.7.25449.3.7.2551,022
19549.3.8.0/2249.3.8.1 to 49.3.11.25449.3.11.2551,022
19649.3.12.0/2249.3.12.1 to 49.3.15.25449.3.15.2551,022
19749.3.16.0/2249.3.16.1 to 49.3.19.25449.3.19.2551,022
19849.3.20.0/2249.3.20.1 to 49.3.23.25449.3.23.2551,022
19949.3.24.0/2249.3.24.1 to 49.3.27.25449.3.27.2551,022
20049.3.28.0/2249.3.28.1 to 49.3.31.25449.3.31.2551,022
20149.3.32.0/2249.3.32.1 to 49.3.35.25449.3.35.2551,022
20249.3.36.0/2249.3.36.1 to 49.3.39.25449.3.39.2551,022
20349.3.40.0/2249.3.40.1 to 49.3.43.25449.3.43.2551,022
20449.3.44.0/2249.3.44.1 to 49.3.47.25449.3.47.2551,022
20549.3.48.0/2249.3.48.1 to 49.3.51.25449.3.51.2551,022
20649.3.52.0/2249.3.52.1 to 49.3.55.25449.3.55.2551,022
20749.3.56.0/2249.3.56.1 to 49.3.59.25449.3.59.2551,022
20849.3.60.0/2249.3.60.1 to 49.3.63.25449.3.63.2551,022
20949.3.64.0/2249.3.64.1 to 49.3.67.25449.3.67.2551,022
21049.3.68.0/2249.3.68.1 to 49.3.71.25449.3.71.2551,022
21149.3.72.0/2249.3.72.1 to 49.3.75.25449.3.75.2551,022
21249.3.76.0/2249.3.76.1 to 49.3.79.25449.3.79.2551,022
21349.3.80.0/2249.3.80.1 to 49.3.83.25449.3.83.2551,022
21449.3.84.0/2249.3.84.1 to 49.3.87.25449.3.87.2551,022
21549.3.88.0/2249.3.88.1 to 49.3.91.25449.3.91.2551,022
21649.3.92.0/2249.3.92.1 to 49.3.95.25449.3.95.2551,022
21749.3.96.0/2249.3.96.1 to 49.3.99.25449.3.99.2551,022
21849.3.100.0/2249.3.100.1 to 49.3.103.25449.3.103.2551,022
21949.3.104.0/2249.3.104.1 to 49.3.107.25449.3.107.2551,022
22049.3.108.0/2249.3.108.1 to 49.3.111.25449.3.111.2551,022
22149.3.112.0/2249.3.112.1 to 49.3.115.25449.3.115.2551,022
22249.3.116.0/2249.3.116.1 to 49.3.119.25449.3.119.2551,022
22349.3.120.0/2249.3.120.1 to 49.3.123.25449.3.123.2551,022
22449.3.124.0/2249.3.124.1 to 49.3.127.25449.3.127.2551,022
22549.3.128.0/2249.3.128.1 to 49.3.131.25449.3.131.2551,022
22649.3.132.0/2249.3.132.1 to 49.3.135.25449.3.135.2551,022
22749.3.136.0/2249.3.136.1 to 49.3.139.25449.3.139.2551,022
22849.3.140.0/2249.3.140.1 to 49.3.143.25449.3.143.2551,022
22949.3.144.0/2249.3.144.1 to 49.3.147.25449.3.147.2551,022
23049.3.148.0/2249.3.148.1 to 49.3.151.25449.3.151.2551,022
23149.3.152.0/2249.3.152.1 to 49.3.155.25449.3.155.2551,022
23249.3.156.0/2249.3.156.1 to 49.3.159.25449.3.159.2551,022
23349.3.160.0/2249.3.160.1 to 49.3.163.25449.3.163.2551,022
23449.3.164.0/2249.3.164.1 to 49.3.167.25449.3.167.2551,022
23549.3.168.0/2249.3.168.1 to 49.3.171.25449.3.171.2551,022
23649.3.172.0/2249.3.172.1 to 49.3.175.25449.3.175.2551,022
23749.3.176.0/2249.3.176.1 to 49.3.179.25449.3.179.2551,022
23849.3.180.0/2249.3.180.1 to 49.3.183.25449.3.183.2551,022
23949.3.184.0/2249.3.184.1 to 49.3.187.25449.3.187.2551,022
24049.3.188.0/2249.3.188.1 to 49.3.191.25449.3.191.2551,022
24149.3.192.0/2249.3.192.1 to 49.3.195.25449.3.195.2551,022
24249.3.196.0/2249.3.196.1 to 49.3.199.25449.3.199.2551,022
24349.3.200.0/2249.3.200.1 to 49.3.203.25449.3.203.2551,022
24449.3.204.0/2249.3.204.1 to 49.3.207.25449.3.207.2551,022
24549.3.208.0/2249.3.208.1 to 49.3.211.25449.3.211.2551,022
24649.3.212.0/2249.3.212.1 to 49.3.215.25449.3.215.2551,022
24749.3.216.0/2249.3.216.1 to 49.3.219.25449.3.219.2551,022
24849.3.220.0/2249.3.220.1 to 49.3.223.25449.3.223.2551,022
24949.3.224.0/2249.3.224.1 to 49.3.227.25449.3.227.2551,022
25049.3.228.0/2249.3.228.1 to 49.3.231.25449.3.231.2551,022
25149.3.232.0/2249.3.232.1 to 49.3.235.25449.3.235.2551,022
25249.3.236.0/2249.3.236.1 to 49.3.239.25449.3.239.2551,022
25349.3.240.0/2249.3.240.1 to 49.3.243.25449.3.243.2551,022
25449.3.244.0/2249.3.244.1 to 49.3.247.25449.3.247.2551,022
25549.3.248.0/2249.3.248.1 to 49.3.251.25449.3.251.2551,022
25649.3.252.0/2249.3.252.1 to 49.3.255.25449.3.255.2551,022

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.