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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.

Network48.0.0.0/5
Usable hosts134,217,726
Subnet mask248.0.0.0
Addresses134,217,728
Network address
48.0.0.0
Broadcast address
55.255.255.255
First usable
48.0.0.1
Last usable
55.255.255.254
Usable hosts
134,217,726 (134,217,728 less the network and broadcast addresses)
Subnet mask
248.0.0.0
Wildcard mask
7.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/5
Type
Public public
Old class
A (default /8)
As numbers
Hex 30000000 · Integer 805306368 to 939524095
Reverse DNS zones
48.in-addr.arpa
49.in-addr.arpa
50.in-addr.arpa
51.in-addr.arpa
52.in-addr.arpa
53.in-addr.arpa
54.in-addr.arpa
55.in-addr.arpa
/5 is not on a 8-bit boundary, so it takes 8 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110000.00000000.00000000.0000000048.0.0.0
Subnet mask11111000.00000000.00000000.00000000248.0.0.0
Network00110000.00000000.00000000.0000000048.0.0.0
Broadcast00110111.11111111.11111111.1111111155.255.255.255
Split into smaller subnets/13
/6 (2)/7 (4)/8 (8)/9 (16)/10 (32)/11 (64)/12 (128)/13 (256)/14 (512)/15 (1,024)/16 (2,048)/17 (4,096)

48.0.0.0/5 makes 256 subnets of /13.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
148.0.0.0/1348.0.0.1 to 48.7.255.25448.7.255.255524,286
248.8.0.0/1348.8.0.1 to 48.15.255.25448.15.255.255524,286
348.16.0.0/1348.16.0.1 to 48.23.255.25448.23.255.255524,286
448.24.0.0/1348.24.0.1 to 48.31.255.25448.31.255.255524,286
548.32.0.0/1348.32.0.1 to 48.39.255.25448.39.255.255524,286
648.40.0.0/1348.40.0.1 to 48.47.255.25448.47.255.255524,286
748.48.0.0/1348.48.0.1 to 48.55.255.25448.55.255.255524,286
848.56.0.0/1348.56.0.1 to 48.63.255.25448.63.255.255524,286
948.64.0.0/1348.64.0.1 to 48.71.255.25448.71.255.255524,286
1048.72.0.0/1348.72.0.1 to 48.79.255.25448.79.255.255524,286
1148.80.0.0/1348.80.0.1 to 48.87.255.25448.87.255.255524,286
1248.88.0.0/1348.88.0.1 to 48.95.255.25448.95.255.255524,286
1348.96.0.0/1348.96.0.1 to 48.103.255.25448.103.255.255524,286
1448.104.0.0/1348.104.0.1 to 48.111.255.25448.111.255.255524,286
1548.112.0.0/1348.112.0.1 to 48.119.255.25448.119.255.255524,286
1648.120.0.0/1348.120.0.1 to 48.127.255.25448.127.255.255524,286
1748.128.0.0/1348.128.0.1 to 48.135.255.25448.135.255.255524,286
1848.136.0.0/1348.136.0.1 to 48.143.255.25448.143.255.255524,286
1948.144.0.0/1348.144.0.1 to 48.151.255.25448.151.255.255524,286
2048.152.0.0/1348.152.0.1 to 48.159.255.25448.159.255.255524,286
2148.160.0.0/1348.160.0.1 to 48.167.255.25448.167.255.255524,286
2248.168.0.0/1348.168.0.1 to 48.175.255.25448.175.255.255524,286
2348.176.0.0/1348.176.0.1 to 48.183.255.25448.183.255.255524,286
2448.184.0.0/1348.184.0.1 to 48.191.255.25448.191.255.255524,286
2548.192.0.0/1348.192.0.1 to 48.199.255.25448.199.255.255524,286
2648.200.0.0/1348.200.0.1 to 48.207.255.25448.207.255.255524,286
2748.208.0.0/1348.208.0.1 to 48.215.255.25448.215.255.255524,286
2848.216.0.0/1348.216.0.1 to 48.223.255.25448.223.255.255524,286
2948.224.0.0/1348.224.0.1 to 48.231.255.25448.231.255.255524,286
3048.232.0.0/1348.232.0.1 to 48.239.255.25448.239.255.255524,286
3148.240.0.0/1348.240.0.1 to 48.247.255.25448.247.255.255524,286
3248.248.0.0/1348.248.0.1 to 48.255.255.25448.255.255.255524,286
3349.0.0.0/1349.0.0.1 to 49.7.255.25449.7.255.255524,286
3449.8.0.0/1349.8.0.1 to 49.15.255.25449.15.255.255524,286
3549.16.0.0/1349.16.0.1 to 49.23.255.25449.23.255.255524,286
3649.24.0.0/1349.24.0.1 to 49.31.255.25449.31.255.255524,286
3749.32.0.0/1349.32.0.1 to 49.39.255.25449.39.255.255524,286
3849.40.0.0/1349.40.0.1 to 49.47.255.25449.47.255.255524,286
3949.48.0.0/1349.48.0.1 to 49.55.255.25449.55.255.255524,286
4049.56.0.0/1349.56.0.1 to 49.63.255.25449.63.255.255524,286
4149.64.0.0/1349.64.0.1 to 49.71.255.25449.71.255.255524,286
4249.72.0.0/1349.72.0.1 to 49.79.255.25449.79.255.255524,286
4349.80.0.0/1349.80.0.1 to 49.87.255.25449.87.255.255524,286
4449.88.0.0/1349.88.0.1 to 49.95.255.25449.95.255.255524,286
4549.96.0.0/1349.96.0.1 to 49.103.255.25449.103.255.255524,286
4649.104.0.0/1349.104.0.1 to 49.111.255.25449.111.255.255524,286
4749.112.0.0/1349.112.0.1 to 49.119.255.25449.119.255.255524,286
4849.120.0.0/1349.120.0.1 to 49.127.255.25449.127.255.255524,286
4949.128.0.0/1349.128.0.1 to 49.135.255.25449.135.255.255524,286
5049.136.0.0/1349.136.0.1 to 49.143.255.25449.143.255.255524,286
5149.144.0.0/1349.144.0.1 to 49.151.255.25449.151.255.255524,286
5249.152.0.0/1349.152.0.1 to 49.159.255.25449.159.255.255524,286
5349.160.0.0/1349.160.0.1 to 49.167.255.25449.167.255.255524,286
5449.168.0.0/1349.168.0.1 to 49.175.255.25449.175.255.255524,286
5549.176.0.0/1349.176.0.1 to 49.183.255.25449.183.255.255524,286
5649.184.0.0/1349.184.0.1 to 49.191.255.25449.191.255.255524,286
5749.192.0.0/1349.192.0.1 to 49.199.255.25449.199.255.255524,286
5849.200.0.0/1349.200.0.1 to 49.207.255.25449.207.255.255524,286
5949.208.0.0/1349.208.0.1 to 49.215.255.25449.215.255.255524,286
6049.216.0.0/1349.216.0.1 to 49.223.255.25449.223.255.255524,286
6149.224.0.0/1349.224.0.1 to 49.231.255.25449.231.255.255524,286
6249.232.0.0/1349.232.0.1 to 49.239.255.25449.239.255.255524,286
6349.240.0.0/1349.240.0.1 to 49.247.255.25449.247.255.255524,286
6449.248.0.0/1349.248.0.1 to 49.255.255.25449.255.255.255524,286
6550.0.0.0/1350.0.0.1 to 50.7.255.25450.7.255.255524,286
6650.8.0.0/1350.8.0.1 to 50.15.255.25450.15.255.255524,286
6750.16.0.0/1350.16.0.1 to 50.23.255.25450.23.255.255524,286
6850.24.0.0/1350.24.0.1 to 50.31.255.25450.31.255.255524,286
6950.32.0.0/1350.32.0.1 to 50.39.255.25450.39.255.255524,286
7050.40.0.0/1350.40.0.1 to 50.47.255.25450.47.255.255524,286
7150.48.0.0/1350.48.0.1 to 50.55.255.25450.55.255.255524,286
7250.56.0.0/1350.56.0.1 to 50.63.255.25450.63.255.255524,286
7350.64.0.0/1350.64.0.1 to 50.71.255.25450.71.255.255524,286
7450.72.0.0/1350.72.0.1 to 50.79.255.25450.79.255.255524,286
7550.80.0.0/1350.80.0.1 to 50.87.255.25450.87.255.255524,286
7650.88.0.0/1350.88.0.1 to 50.95.255.25450.95.255.255524,286
7750.96.0.0/1350.96.0.1 to 50.103.255.25450.103.255.255524,286
7850.104.0.0/1350.104.0.1 to 50.111.255.25450.111.255.255524,286
7950.112.0.0/1350.112.0.1 to 50.119.255.25450.119.255.255524,286
8050.120.0.0/1350.120.0.1 to 50.127.255.25450.127.255.255524,286
8150.128.0.0/1350.128.0.1 to 50.135.255.25450.135.255.255524,286
8250.136.0.0/1350.136.0.1 to 50.143.255.25450.143.255.255524,286
8350.144.0.0/1350.144.0.1 to 50.151.255.25450.151.255.255524,286
8450.152.0.0/1350.152.0.1 to 50.159.255.25450.159.255.255524,286
8550.160.0.0/1350.160.0.1 to 50.167.255.25450.167.255.255524,286
8650.168.0.0/1350.168.0.1 to 50.175.255.25450.175.255.255524,286
8750.176.0.0/1350.176.0.1 to 50.183.255.25450.183.255.255524,286
8850.184.0.0/1350.184.0.1 to 50.191.255.25450.191.255.255524,286
8950.192.0.0/1350.192.0.1 to 50.199.255.25450.199.255.255524,286
9050.200.0.0/1350.200.0.1 to 50.207.255.25450.207.255.255524,286
9150.208.0.0/1350.208.0.1 to 50.215.255.25450.215.255.255524,286
9250.216.0.0/1350.216.0.1 to 50.223.255.25450.223.255.255524,286
9350.224.0.0/1350.224.0.1 to 50.231.255.25450.231.255.255524,286
9450.232.0.0/1350.232.0.1 to 50.239.255.25450.239.255.255524,286
9550.240.0.0/1350.240.0.1 to 50.247.255.25450.247.255.255524,286
9650.248.0.0/1350.248.0.1 to 50.255.255.25450.255.255.255524,286
9751.0.0.0/1351.0.0.1 to 51.7.255.25451.7.255.255524,286
9851.8.0.0/1351.8.0.1 to 51.15.255.25451.15.255.255524,286
9951.16.0.0/1351.16.0.1 to 51.23.255.25451.23.255.255524,286
10051.24.0.0/1351.24.0.1 to 51.31.255.25451.31.255.255524,286
10151.32.0.0/1351.32.0.1 to 51.39.255.25451.39.255.255524,286
10251.40.0.0/1351.40.0.1 to 51.47.255.25451.47.255.255524,286
10351.48.0.0/1351.48.0.1 to 51.55.255.25451.55.255.255524,286
10451.56.0.0/1351.56.0.1 to 51.63.255.25451.63.255.255524,286
10551.64.0.0/1351.64.0.1 to 51.71.255.25451.71.255.255524,286
10651.72.0.0/1351.72.0.1 to 51.79.255.25451.79.255.255524,286
10751.80.0.0/1351.80.0.1 to 51.87.255.25451.87.255.255524,286
10851.88.0.0/1351.88.0.1 to 51.95.255.25451.95.255.255524,286
10951.96.0.0/1351.96.0.1 to 51.103.255.25451.103.255.255524,286
11051.104.0.0/1351.104.0.1 to 51.111.255.25451.111.255.255524,286
11151.112.0.0/1351.112.0.1 to 51.119.255.25451.119.255.255524,286
11251.120.0.0/1351.120.0.1 to 51.127.255.25451.127.255.255524,286
11351.128.0.0/1351.128.0.1 to 51.135.255.25451.135.255.255524,286
11451.136.0.0/1351.136.0.1 to 51.143.255.25451.143.255.255524,286
11551.144.0.0/1351.144.0.1 to 51.151.255.25451.151.255.255524,286
11651.152.0.0/1351.152.0.1 to 51.159.255.25451.159.255.255524,286
11751.160.0.0/1351.160.0.1 to 51.167.255.25451.167.255.255524,286
11851.168.0.0/1351.168.0.1 to 51.175.255.25451.175.255.255524,286
11951.176.0.0/1351.176.0.1 to 51.183.255.25451.183.255.255524,286
12051.184.0.0/1351.184.0.1 to 51.191.255.25451.191.255.255524,286
12151.192.0.0/1351.192.0.1 to 51.199.255.25451.199.255.255524,286
12251.200.0.0/1351.200.0.1 to 51.207.255.25451.207.255.255524,286
12351.208.0.0/1351.208.0.1 to 51.215.255.25451.215.255.255524,286
12451.216.0.0/1351.216.0.1 to 51.223.255.25451.223.255.255524,286
12551.224.0.0/1351.224.0.1 to 51.231.255.25451.231.255.255524,286
12651.232.0.0/1351.232.0.1 to 51.239.255.25451.239.255.255524,286
12751.240.0.0/1351.240.0.1 to 51.247.255.25451.247.255.255524,286
12851.248.0.0/1351.248.0.1 to 51.255.255.25451.255.255.255524,286
12952.0.0.0/1352.0.0.1 to 52.7.255.25452.7.255.255524,286
13052.8.0.0/1352.8.0.1 to 52.15.255.25452.15.255.255524,286
13152.16.0.0/1352.16.0.1 to 52.23.255.25452.23.255.255524,286
13252.24.0.0/1352.24.0.1 to 52.31.255.25452.31.255.255524,286
13352.32.0.0/1352.32.0.1 to 52.39.255.25452.39.255.255524,286
13452.40.0.0/1352.40.0.1 to 52.47.255.25452.47.255.255524,286
13552.48.0.0/1352.48.0.1 to 52.55.255.25452.55.255.255524,286
13652.56.0.0/1352.56.0.1 to 52.63.255.25452.63.255.255524,286
13752.64.0.0/1352.64.0.1 to 52.71.255.25452.71.255.255524,286
13852.72.0.0/1352.72.0.1 to 52.79.255.25452.79.255.255524,286
13952.80.0.0/1352.80.0.1 to 52.87.255.25452.87.255.255524,286
14052.88.0.0/1352.88.0.1 to 52.95.255.25452.95.255.255524,286
14152.96.0.0/1352.96.0.1 to 52.103.255.25452.103.255.255524,286
14252.104.0.0/1352.104.0.1 to 52.111.255.25452.111.255.255524,286
14352.112.0.0/1352.112.0.1 to 52.119.255.25452.119.255.255524,286
14452.120.0.0/1352.120.0.1 to 52.127.255.25452.127.255.255524,286
14552.128.0.0/1352.128.0.1 to 52.135.255.25452.135.255.255524,286
14652.136.0.0/1352.136.0.1 to 52.143.255.25452.143.255.255524,286
14752.144.0.0/1352.144.0.1 to 52.151.255.25452.151.255.255524,286
14852.152.0.0/1352.152.0.1 to 52.159.255.25452.159.255.255524,286
14952.160.0.0/1352.160.0.1 to 52.167.255.25452.167.255.255524,286
15052.168.0.0/1352.168.0.1 to 52.175.255.25452.175.255.255524,286
15152.176.0.0/1352.176.0.1 to 52.183.255.25452.183.255.255524,286
15252.184.0.0/1352.184.0.1 to 52.191.255.25452.191.255.255524,286
15352.192.0.0/1352.192.0.1 to 52.199.255.25452.199.255.255524,286
15452.200.0.0/1352.200.0.1 to 52.207.255.25452.207.255.255524,286
15552.208.0.0/1352.208.0.1 to 52.215.255.25452.215.255.255524,286
15652.216.0.0/1352.216.0.1 to 52.223.255.25452.223.255.255524,286
15752.224.0.0/1352.224.0.1 to 52.231.255.25452.231.255.255524,286
15852.232.0.0/1352.232.0.1 to 52.239.255.25452.239.255.255524,286
15952.240.0.0/1352.240.0.1 to 52.247.255.25452.247.255.255524,286
16052.248.0.0/1352.248.0.1 to 52.255.255.25452.255.255.255524,286
16153.0.0.0/1353.0.0.1 to 53.7.255.25453.7.255.255524,286
16253.8.0.0/1353.8.0.1 to 53.15.255.25453.15.255.255524,286
16353.16.0.0/1353.16.0.1 to 53.23.255.25453.23.255.255524,286
16453.24.0.0/1353.24.0.1 to 53.31.255.25453.31.255.255524,286
16553.32.0.0/1353.32.0.1 to 53.39.255.25453.39.255.255524,286
16653.40.0.0/1353.40.0.1 to 53.47.255.25453.47.255.255524,286
16753.48.0.0/1353.48.0.1 to 53.55.255.25453.55.255.255524,286
16853.56.0.0/1353.56.0.1 to 53.63.255.25453.63.255.255524,286
16953.64.0.0/1353.64.0.1 to 53.71.255.25453.71.255.255524,286
17053.72.0.0/1353.72.0.1 to 53.79.255.25453.79.255.255524,286
17153.80.0.0/1353.80.0.1 to 53.87.255.25453.87.255.255524,286
17253.88.0.0/1353.88.0.1 to 53.95.255.25453.95.255.255524,286
17353.96.0.0/1353.96.0.1 to 53.103.255.25453.103.255.255524,286
17453.104.0.0/1353.104.0.1 to 53.111.255.25453.111.255.255524,286
17553.112.0.0/1353.112.0.1 to 53.119.255.25453.119.255.255524,286
17653.120.0.0/1353.120.0.1 to 53.127.255.25453.127.255.255524,286
17753.128.0.0/1353.128.0.1 to 53.135.255.25453.135.255.255524,286
17853.136.0.0/1353.136.0.1 to 53.143.255.25453.143.255.255524,286
17953.144.0.0/1353.144.0.1 to 53.151.255.25453.151.255.255524,286
18053.152.0.0/1353.152.0.1 to 53.159.255.25453.159.255.255524,286
18153.160.0.0/1353.160.0.1 to 53.167.255.25453.167.255.255524,286
18253.168.0.0/1353.168.0.1 to 53.175.255.25453.175.255.255524,286
18353.176.0.0/1353.176.0.1 to 53.183.255.25453.183.255.255524,286
18453.184.0.0/1353.184.0.1 to 53.191.255.25453.191.255.255524,286
18553.192.0.0/1353.192.0.1 to 53.199.255.25453.199.255.255524,286
18653.200.0.0/1353.200.0.1 to 53.207.255.25453.207.255.255524,286
18753.208.0.0/1353.208.0.1 to 53.215.255.25453.215.255.255524,286
18853.216.0.0/1353.216.0.1 to 53.223.255.25453.223.255.255524,286
18953.224.0.0/1353.224.0.1 to 53.231.255.25453.231.255.255524,286
19053.232.0.0/1353.232.0.1 to 53.239.255.25453.239.255.255524,286
19153.240.0.0/1353.240.0.1 to 53.247.255.25453.247.255.255524,286
19253.248.0.0/1353.248.0.1 to 53.255.255.25453.255.255.255524,286
19354.0.0.0/1354.0.0.1 to 54.7.255.25454.7.255.255524,286
19454.8.0.0/1354.8.0.1 to 54.15.255.25454.15.255.255524,286
19554.16.0.0/1354.16.0.1 to 54.23.255.25454.23.255.255524,286
19654.24.0.0/1354.24.0.1 to 54.31.255.25454.31.255.255524,286
19754.32.0.0/1354.32.0.1 to 54.39.255.25454.39.255.255524,286
19854.40.0.0/1354.40.0.1 to 54.47.255.25454.47.255.255524,286
19954.48.0.0/1354.48.0.1 to 54.55.255.25454.55.255.255524,286
20054.56.0.0/1354.56.0.1 to 54.63.255.25454.63.255.255524,286
20154.64.0.0/1354.64.0.1 to 54.71.255.25454.71.255.255524,286
20254.72.0.0/1354.72.0.1 to 54.79.255.25454.79.255.255524,286
20354.80.0.0/1354.80.0.1 to 54.87.255.25454.87.255.255524,286
20454.88.0.0/1354.88.0.1 to 54.95.255.25454.95.255.255524,286
20554.96.0.0/1354.96.0.1 to 54.103.255.25454.103.255.255524,286
20654.104.0.0/1354.104.0.1 to 54.111.255.25454.111.255.255524,286
20754.112.0.0/1354.112.0.1 to 54.119.255.25454.119.255.255524,286
20854.120.0.0/1354.120.0.1 to 54.127.255.25454.127.255.255524,286
20954.128.0.0/1354.128.0.1 to 54.135.255.25454.135.255.255524,286
21054.136.0.0/1354.136.0.1 to 54.143.255.25454.143.255.255524,286
21154.144.0.0/1354.144.0.1 to 54.151.255.25454.151.255.255524,286
21254.152.0.0/1354.152.0.1 to 54.159.255.25454.159.255.255524,286
21354.160.0.0/1354.160.0.1 to 54.167.255.25454.167.255.255524,286
21454.168.0.0/1354.168.0.1 to 54.175.255.25454.175.255.255524,286
21554.176.0.0/1354.176.0.1 to 54.183.255.25454.183.255.255524,286
21654.184.0.0/1354.184.0.1 to 54.191.255.25454.191.255.255524,286
21754.192.0.0/1354.192.0.1 to 54.199.255.25454.199.255.255524,286
21854.200.0.0/1354.200.0.1 to 54.207.255.25454.207.255.255524,286
21954.208.0.0/1354.208.0.1 to 54.215.255.25454.215.255.255524,286
22054.216.0.0/1354.216.0.1 to 54.223.255.25454.223.255.255524,286
22154.224.0.0/1354.224.0.1 to 54.231.255.25454.231.255.255524,286
22254.232.0.0/1354.232.0.1 to 54.239.255.25454.239.255.255524,286
22354.240.0.0/1354.240.0.1 to 54.247.255.25454.247.255.255524,286
22454.248.0.0/1354.248.0.1 to 54.255.255.25454.255.255.255524,286
22555.0.0.0/1355.0.0.1 to 55.7.255.25455.7.255.255524,286
22655.8.0.0/1355.8.0.1 to 55.15.255.25455.15.255.255524,286
22755.16.0.0/1355.16.0.1 to 55.23.255.25455.23.255.255524,286
22855.24.0.0/1355.24.0.1 to 55.31.255.25455.31.255.255524,286
22955.32.0.0/1355.32.0.1 to 55.39.255.25455.39.255.255524,286
23055.40.0.0/1355.40.0.1 to 55.47.255.25455.47.255.255524,286
23155.48.0.0/1355.48.0.1 to 55.55.255.25455.55.255.255524,286
23255.56.0.0/1355.56.0.1 to 55.63.255.25455.63.255.255524,286
23355.64.0.0/1355.64.0.1 to 55.71.255.25455.71.255.255524,286
23455.72.0.0/1355.72.0.1 to 55.79.255.25455.79.255.255524,286
23555.80.0.0/1355.80.0.1 to 55.87.255.25455.87.255.255524,286
23655.88.0.0/1355.88.0.1 to 55.95.255.25455.95.255.255524,286
23755.96.0.0/1355.96.0.1 to 55.103.255.25455.103.255.255524,286
23855.104.0.0/1355.104.0.1 to 55.111.255.25455.111.255.255524,286
23955.112.0.0/1355.112.0.1 to 55.119.255.25455.119.255.255524,286
24055.120.0.0/1355.120.0.1 to 55.127.255.25455.127.255.255524,286
24155.128.0.0/1355.128.0.1 to 55.135.255.25455.135.255.255524,286
24255.136.0.0/1355.136.0.1 to 55.143.255.25455.143.255.255524,286
24355.144.0.0/1355.144.0.1 to 55.151.255.25455.151.255.255524,286
24455.152.0.0/1355.152.0.1 to 55.159.255.25455.159.255.255524,286
24555.160.0.0/1355.160.0.1 to 55.167.255.25455.167.255.255524,286
24655.168.0.0/1355.168.0.1 to 55.175.255.25455.175.255.255524,286
24755.176.0.0/1355.176.0.1 to 55.183.255.25455.183.255.255524,286
24855.184.0.0/1355.184.0.1 to 55.191.255.25455.191.255.255524,286
24955.192.0.0/1355.192.0.1 to 55.199.255.25455.199.255.255524,286
25055.200.0.0/1355.200.0.1 to 55.207.255.25455.207.255.255524,286
25155.208.0.0/1355.208.0.1 to 55.215.255.25455.215.255.255524,286
25255.216.0.0/1355.216.0.1 to 55.223.255.25455.223.255.255524,286
25355.224.0.0/1355.224.0.1 to 55.231.255.25455.231.255.255524,286
25455.232.0.0/1355.232.0.1 to 55.239.255.25455.239.255.255524,286
25555.240.0.0/1355.240.0.1 to 55.247.255.25455.247.255.255524,286
25655.248.0.0/1355.248.0.1 to 55.255.255.25455.255.255.255524,286

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.