IPv4 Subnet Calculator
Enter an IP with a CIDR prefix or a subnet mask to see its network, broadcast, host range, and host count. You can also split the network into smaller subnets.
private IP (RFC 1918)10.51.192.0/18
network10.51.192.0/18
broadcast10.51.255.255
first host10.51.192.1
last host10.51.255.254
subnet mask255.255.192.0
wildcard0.0.63.255
addresses16,384
usable hosts16,382
classA
ipcalc 10.51.192.0/18
address00001010.00110011.11000000.00000000
subnet mask11111111.11111111.11000000.00000000
network00001010.00110011.11000000.00000000
broadcast00001010.00110011.11111111.11111111
green = network part, grey = host part
hex0x0a33c000
decimal171163648
reverse dns0.192.51.10.in-addr.arpa
ipv4-mapped::ffff:a33:c000
/18 split into /25 · 128 subnets
close ×| # | network | host range | broadcast |
|---|---|---|---|
| 1 | 10.51.192.0/25 | 10.51.192.1 – 10.51.192.126 | 10.51.192.127 |
| 2 | 10.51.192.128/25 | 10.51.192.129 – 10.51.192.254 | 10.51.192.255 |
| 3 | 10.51.193.0/25 | 10.51.193.1 – 10.51.193.126 | 10.51.193.127 |
| 4 | 10.51.193.128/25 | 10.51.193.129 – 10.51.193.254 | 10.51.193.255 |
| 5 | 10.51.194.0/25 | 10.51.194.1 – 10.51.194.126 | 10.51.194.127 |
| 6 | 10.51.194.128/25 | 10.51.194.129 – 10.51.194.254 | 10.51.194.255 |
| 7 | 10.51.195.0/25 | 10.51.195.1 – 10.51.195.126 | 10.51.195.127 |
| 8 | 10.51.195.128/25 | 10.51.195.129 – 10.51.195.254 | 10.51.195.255 |
| 9 | 10.51.196.0/25 | 10.51.196.1 – 10.51.196.126 | 10.51.196.127 |
| 10 | 10.51.196.128/25 | 10.51.196.129 – 10.51.196.254 | 10.51.196.255 |
| 11 | 10.51.197.0/25 | 10.51.197.1 – 10.51.197.126 | 10.51.197.127 |
| 12 | 10.51.197.128/25 | 10.51.197.129 – 10.51.197.254 | 10.51.197.255 |
| 13 | 10.51.198.0/25 | 10.51.198.1 – 10.51.198.126 | 10.51.198.127 |
| 14 | 10.51.198.128/25 | 10.51.198.129 – 10.51.198.254 | 10.51.198.255 |
| 15 | 10.51.199.0/25 | 10.51.199.1 – 10.51.199.126 | 10.51.199.127 |
| 16 | 10.51.199.128/25 | 10.51.199.129 – 10.51.199.254 | 10.51.199.255 |
| 17 | 10.51.200.0/25 | 10.51.200.1 – 10.51.200.126 | 10.51.200.127 |
| 18 | 10.51.200.128/25 | 10.51.200.129 – 10.51.200.254 | 10.51.200.255 |
| 19 | 10.51.201.0/25 | 10.51.201.1 – 10.51.201.126 | 10.51.201.127 |
| 20 | 10.51.201.128/25 | 10.51.201.129 – 10.51.201.254 | 10.51.201.255 |
| 21 | 10.51.202.0/25 | 10.51.202.1 – 10.51.202.126 | 10.51.202.127 |
| 22 | 10.51.202.128/25 | 10.51.202.129 – 10.51.202.254 | 10.51.202.255 |
| 23 | 10.51.203.0/25 | 10.51.203.1 – 10.51.203.126 | 10.51.203.127 |
| 24 | 10.51.203.128/25 | 10.51.203.129 – 10.51.203.254 | 10.51.203.255 |
| 25 | 10.51.204.0/25 | 10.51.204.1 – 10.51.204.126 | 10.51.204.127 |
| 26 | 10.51.204.128/25 | 10.51.204.129 – 10.51.204.254 | 10.51.204.255 |
| 27 | 10.51.205.0/25 | 10.51.205.1 – 10.51.205.126 | 10.51.205.127 |
| 28 | 10.51.205.128/25 | 10.51.205.129 – 10.51.205.254 | 10.51.205.255 |
| 29 | 10.51.206.0/25 | 10.51.206.1 – 10.51.206.126 | 10.51.206.127 |
| 30 | 10.51.206.128/25 | 10.51.206.129 – 10.51.206.254 | 10.51.206.255 |
| 31 | 10.51.207.0/25 | 10.51.207.1 – 10.51.207.126 | 10.51.207.127 |
| 32 | 10.51.207.128/25 | 10.51.207.129 – 10.51.207.254 | 10.51.207.255 |
| 33 | 10.51.208.0/25 | 10.51.208.1 – 10.51.208.126 | 10.51.208.127 |
| 34 | 10.51.208.128/25 | 10.51.208.129 – 10.51.208.254 | 10.51.208.255 |
| 35 | 10.51.209.0/25 | 10.51.209.1 – 10.51.209.126 | 10.51.209.127 |
| 36 | 10.51.209.128/25 | 10.51.209.129 – 10.51.209.254 | 10.51.209.255 |
| 37 | 10.51.210.0/25 | 10.51.210.1 – 10.51.210.126 | 10.51.210.127 |
| 38 | 10.51.210.128/25 | 10.51.210.129 – 10.51.210.254 | 10.51.210.255 |
| 39 | 10.51.211.0/25 | 10.51.211.1 – 10.51.211.126 | 10.51.211.127 |
| 40 | 10.51.211.128/25 | 10.51.211.129 – 10.51.211.254 | 10.51.211.255 |
| 41 | 10.51.212.0/25 | 10.51.212.1 – 10.51.212.126 | 10.51.212.127 |
| 42 | 10.51.212.128/25 | 10.51.212.129 – 10.51.212.254 | 10.51.212.255 |
| 43 | 10.51.213.0/25 | 10.51.213.1 – 10.51.213.126 | 10.51.213.127 |
| 44 | 10.51.213.128/25 | 10.51.213.129 – 10.51.213.254 | 10.51.213.255 |
| 45 | 10.51.214.0/25 | 10.51.214.1 – 10.51.214.126 | 10.51.214.127 |
| 46 | 10.51.214.128/25 | 10.51.214.129 – 10.51.214.254 | 10.51.214.255 |
| 47 | 10.51.215.0/25 | 10.51.215.1 – 10.51.215.126 | 10.51.215.127 |
| 48 | 10.51.215.128/25 | 10.51.215.129 – 10.51.215.254 | 10.51.215.255 |
| 49 | 10.51.216.0/25 | 10.51.216.1 – 10.51.216.126 | 10.51.216.127 |
| 50 | 10.51.216.128/25 | 10.51.216.129 – 10.51.216.254 | 10.51.216.255 |
| 51 | 10.51.217.0/25 | 10.51.217.1 – 10.51.217.126 | 10.51.217.127 |
| 52 | 10.51.217.128/25 | 10.51.217.129 – 10.51.217.254 | 10.51.217.255 |
| 53 | 10.51.218.0/25 | 10.51.218.1 – 10.51.218.126 | 10.51.218.127 |
| 54 | 10.51.218.128/25 | 10.51.218.129 – 10.51.218.254 | 10.51.218.255 |
| 55 | 10.51.219.0/25 | 10.51.219.1 – 10.51.219.126 | 10.51.219.127 |
| 56 | 10.51.219.128/25 | 10.51.219.129 – 10.51.219.254 | 10.51.219.255 |
| 57 | 10.51.220.0/25 | 10.51.220.1 – 10.51.220.126 | 10.51.220.127 |
| 58 | 10.51.220.128/25 | 10.51.220.129 – 10.51.220.254 | 10.51.220.255 |
| 59 | 10.51.221.0/25 | 10.51.221.1 – 10.51.221.126 | 10.51.221.127 |
| 60 | 10.51.221.128/25 | 10.51.221.129 – 10.51.221.254 | 10.51.221.255 |
| 61 | 10.51.222.0/25 | 10.51.222.1 – 10.51.222.126 | 10.51.222.127 |
| 62 | 10.51.222.128/25 | 10.51.222.129 – 10.51.222.254 | 10.51.222.255 |
| 63 | 10.51.223.0/25 | 10.51.223.1 – 10.51.223.126 | 10.51.223.127 |
| 64 | 10.51.223.128/25 | 10.51.223.129 – 10.51.223.254 | 10.51.223.255 |
| 65 | 10.51.224.0/25 | 10.51.224.1 – 10.51.224.126 | 10.51.224.127 |
| 66 | 10.51.224.128/25 | 10.51.224.129 – 10.51.224.254 | 10.51.224.255 |
| 67 | 10.51.225.0/25 | 10.51.225.1 – 10.51.225.126 | 10.51.225.127 |
| 68 | 10.51.225.128/25 | 10.51.225.129 – 10.51.225.254 | 10.51.225.255 |
| 69 | 10.51.226.0/25 | 10.51.226.1 – 10.51.226.126 | 10.51.226.127 |
| 70 | 10.51.226.128/25 | 10.51.226.129 – 10.51.226.254 | 10.51.226.255 |
| 71 | 10.51.227.0/25 | 10.51.227.1 – 10.51.227.126 | 10.51.227.127 |
| 72 | 10.51.227.128/25 | 10.51.227.129 – 10.51.227.254 | 10.51.227.255 |
| 73 | 10.51.228.0/25 | 10.51.228.1 – 10.51.228.126 | 10.51.228.127 |
| 74 | 10.51.228.128/25 | 10.51.228.129 – 10.51.228.254 | 10.51.228.255 |
| 75 | 10.51.229.0/25 | 10.51.229.1 – 10.51.229.126 | 10.51.229.127 |
| 76 | 10.51.229.128/25 | 10.51.229.129 – 10.51.229.254 | 10.51.229.255 |
| 77 | 10.51.230.0/25 | 10.51.230.1 – 10.51.230.126 | 10.51.230.127 |
| 78 | 10.51.230.128/25 | 10.51.230.129 – 10.51.230.254 | 10.51.230.255 |
| 79 | 10.51.231.0/25 | 10.51.231.1 – 10.51.231.126 | 10.51.231.127 |
| 80 | 10.51.231.128/25 | 10.51.231.129 – 10.51.231.254 | 10.51.231.255 |
| 81 | 10.51.232.0/25 | 10.51.232.1 – 10.51.232.126 | 10.51.232.127 |
| 82 | 10.51.232.128/25 | 10.51.232.129 – 10.51.232.254 | 10.51.232.255 |
| 83 | 10.51.233.0/25 | 10.51.233.1 – 10.51.233.126 | 10.51.233.127 |
| 84 | 10.51.233.128/25 | 10.51.233.129 – 10.51.233.254 | 10.51.233.255 |
| 85 | 10.51.234.0/25 | 10.51.234.1 – 10.51.234.126 | 10.51.234.127 |
| 86 | 10.51.234.128/25 | 10.51.234.129 – 10.51.234.254 | 10.51.234.255 |
| 87 | 10.51.235.0/25 | 10.51.235.1 – 10.51.235.126 | 10.51.235.127 |
| 88 | 10.51.235.128/25 | 10.51.235.129 – 10.51.235.254 | 10.51.235.255 |
| 89 | 10.51.236.0/25 | 10.51.236.1 – 10.51.236.126 | 10.51.236.127 |
| 90 | 10.51.236.128/25 | 10.51.236.129 – 10.51.236.254 | 10.51.236.255 |
| 91 | 10.51.237.0/25 | 10.51.237.1 – 10.51.237.126 | 10.51.237.127 |
| 92 | 10.51.237.128/25 | 10.51.237.129 – 10.51.237.254 | 10.51.237.255 |
| 93 | 10.51.238.0/25 | 10.51.238.1 – 10.51.238.126 | 10.51.238.127 |
| 94 | 10.51.238.128/25 | 10.51.238.129 – 10.51.238.254 | 10.51.238.255 |
| 95 | 10.51.239.0/25 | 10.51.239.1 – 10.51.239.126 | 10.51.239.127 |
| 96 | 10.51.239.128/25 | 10.51.239.129 – 10.51.239.254 | 10.51.239.255 |
| 97 | 10.51.240.0/25 | 10.51.240.1 – 10.51.240.126 | 10.51.240.127 |
| 98 | 10.51.240.128/25 | 10.51.240.129 – 10.51.240.254 | 10.51.240.255 |
| 99 | 10.51.241.0/25 | 10.51.241.1 – 10.51.241.126 | 10.51.241.127 |
| 100 | 10.51.241.128/25 | 10.51.241.129 – 10.51.241.254 | 10.51.241.255 |
| 101 | 10.51.242.0/25 | 10.51.242.1 – 10.51.242.126 | 10.51.242.127 |
| 102 | 10.51.242.128/25 | 10.51.242.129 – 10.51.242.254 | 10.51.242.255 |
| 103 | 10.51.243.0/25 | 10.51.243.1 – 10.51.243.126 | 10.51.243.127 |
| 104 | 10.51.243.128/25 | 10.51.243.129 – 10.51.243.254 | 10.51.243.255 |
| 105 | 10.51.244.0/25 | 10.51.244.1 – 10.51.244.126 | 10.51.244.127 |
| 106 | 10.51.244.128/25 | 10.51.244.129 – 10.51.244.254 | 10.51.244.255 |
| 107 | 10.51.245.0/25 | 10.51.245.1 – 10.51.245.126 | 10.51.245.127 |
| 108 | 10.51.245.128/25 | 10.51.245.129 – 10.51.245.254 | 10.51.245.255 |
| 109 | 10.51.246.0/25 | 10.51.246.1 – 10.51.246.126 | 10.51.246.127 |
| 110 | 10.51.246.128/25 | 10.51.246.129 – 10.51.246.254 | 10.51.246.255 |
| 111 | 10.51.247.0/25 | 10.51.247.1 – 10.51.247.126 | 10.51.247.127 |
| 112 | 10.51.247.128/25 | 10.51.247.129 – 10.51.247.254 | 10.51.247.255 |
| 113 | 10.51.248.0/25 | 10.51.248.1 – 10.51.248.126 | 10.51.248.127 |
| 114 | 10.51.248.128/25 | 10.51.248.129 – 10.51.248.254 | 10.51.248.255 |
| 115 | 10.51.249.0/25 | 10.51.249.1 – 10.51.249.126 | 10.51.249.127 |
| 116 | 10.51.249.128/25 | 10.51.249.129 – 10.51.249.254 | 10.51.249.255 |
| 117 | 10.51.250.0/25 | 10.51.250.1 – 10.51.250.126 | 10.51.250.127 |
| 118 | 10.51.250.128/25 | 10.51.250.129 – 10.51.250.254 | 10.51.250.255 |
| 119 | 10.51.251.0/25 | 10.51.251.1 – 10.51.251.126 | 10.51.251.127 |
| 120 | 10.51.251.128/25 | 10.51.251.129 – 10.51.251.254 | 10.51.251.255 |
| 121 | 10.51.252.0/25 | 10.51.252.1 – 10.51.252.126 | 10.51.252.127 |
| 122 | 10.51.252.128/25 | 10.51.252.129 – 10.51.252.254 | 10.51.252.255 |
| 123 | 10.51.253.0/25 | 10.51.253.1 – 10.51.253.126 | 10.51.253.127 |
| 124 | 10.51.253.128/25 | 10.51.253.129 – 10.51.253.254 | 10.51.253.255 |
| 125 | 10.51.254.0/25 | 10.51.254.1 – 10.51.254.126 | 10.51.254.127 |
| 126 | 10.51.254.128/25 | 10.51.254.129 – 10.51.254.254 | 10.51.254.255 |
| 127 | 10.51.255.0/25 | 10.51.255.1 – 10.51.255.126 | 10.51.255.127 |
| 128 | 10.51.255.128/25 | 10.51.255.129 – 10.51.255.254 | 10.51.255.255 |
01 / table
IPv4 CIDR prefix table.
Click a prefix longer than your network to split it into subnets.
| prefix | subnet mask | addresses | hosts | in your /18 |
|---|---|---|---|---|
| /0 | 0.0.0.0 | 4,294,967,296 | 4,294,967,294 | - |
| /1 | 128.0.0.0 | 2,147,483,648 | 2,147,483,646 | - |
| /2 | 192.0.0.0 | 1,073,741,824 | 1,073,741,822 | - |
| /3 | 224.0.0.0 | 536,870,912 | 536,870,910 | - |
| /4 | 240.0.0.0 | 268,435,456 | 268,435,454 | - |
| /5 | 248.0.0.0 | 134,217,728 | 134,217,726 | - |
| /6 | 252.0.0.0 | 67,108,864 | 67,108,862 | - |
| /7 | 254.0.0.0 | 33,554,432 | 33,554,430 | - |
| /8 | 255.0.0.0 | 16,777,216 | 16,777,214 | - |
| /9 | 255.128.0.0 | 8,388,608 | 8,388,606 | - |
| /10 | 255.192.0.0 | 4,194,304 | 4,194,302 | - |
| /11 | 255.224.0.0 | 2,097,152 | 2,097,150 | - |
| /12 | 255.240.0.0 | 1,048,576 | 1,048,574 | - |
| /13 | 255.248.0.0 | 524,288 | 524,286 | - |
| /14 | 255.252.0.0 | 262,144 | 262,142 | - |
| /15 | 255.254.0.0 | 131,072 | 131,070 | - |
| /16 | 255.255.0.0 | 65,536 | 65,534 | - |
| /17 | 255.255.128.0 | 32,768 | 32,766 | - |
| /18 | 255.255.192.0 | 16,384 | 16,382 | 1 |
| /19 | 255.255.224.0 | 8,192 | 8,190 | 2 split → |
| /20 | 255.255.240.0 | 4,096 | 4,094 | 4 split → |
| /21 | 255.255.248.0 | 2,048 | 2,046 | 8 split → |
| /22 | 255.255.252.0 | 1,024 | 1,022 | 16 split → |
| /23 | 255.255.254.0 | 512 | 510 | 32 split → |
| /24 | 255.255.255.0 | 256 | 254 | 64 split → |
| /25 | 255.255.255.128 | 128 | 126 | 128 split → |
| /26 | 255.255.255.192 | 64 | 62 | 256 split → |
| /27 | 255.255.255.224 | 32 | 30 | 512 split → |
| /28 | 255.255.255.240 | 16 | 14 | 1,024 split → |
| /29 | 255.255.255.248 | 8 | 6 | 2,048 split → |
| /30 | 255.255.255.252 | 4 | 2 | 4,096 split → |
| /31 | 255.255.255.254 | 2 | 2 | 8,192 split → |
| /32 | 255.255.255.255 | 1 | 1 | 16,384 split → |
02 / faq
About this calculator.
How do I use this subnet calculator?
▼
Type an IP address followed by a prefix, like 192.168.1.10/24, or by a subnet mask, like 192.168.1.10 255.255.255.0. Without a prefix it uses /24. Click a row in the table to split the network into smaller subnets.
Why are usable hosts always 2 fewer?
▼
The first address in a subnet is the network address and the last is the broadcast address, so neither can go to a device. The exceptions are /31 (point-to-point links, RFC 3021) and /32 (a single address), which use every address.
Can I use it from a terminal?
▼
Yes. curl 'ipku.in/en/tools/ipv4-subnet-calculator?q=192.168.1.10/24' returns the result as plain text.