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)10.25.128.0/18
network10.25.128.0/18
broadcast10.25.191.255
first host10.25.128.1
last host10.25.191.254
subnet mask255.255.192.0
wildcard0.0.63.255
addresses16,384
usable hosts16,382
classA
ipcalc 10.25.128.0/18
address00001010.00011001.10000000.00000000
subnet mask11111111.11111111.11000000.00000000
network00001010.00011001.10000000.00000000
broadcast00001010.00011001.10111111.11111111
green = network part, grey = host part
hex0x0a198000
decimal169443328
reverse dns0.128.25.10.in-addr.arpa
ipv4-mapped::ffff:a19:8000
/18 split into /25 · 128 subnets
close ×| # | network | host range | broadcast |
|---|---|---|---|
| 1 | 10.25.128.0/25 | 10.25.128.1 – 10.25.128.126 | 10.25.128.127 |
| 2 | 10.25.128.128/25 | 10.25.128.129 – 10.25.128.254 | 10.25.128.255 |
| 3 | 10.25.129.0/25 | 10.25.129.1 – 10.25.129.126 | 10.25.129.127 |
| 4 | 10.25.129.128/25 | 10.25.129.129 – 10.25.129.254 | 10.25.129.255 |
| 5 | 10.25.130.0/25 | 10.25.130.1 – 10.25.130.126 | 10.25.130.127 |
| 6 | 10.25.130.128/25 | 10.25.130.129 – 10.25.130.254 | 10.25.130.255 |
| 7 | 10.25.131.0/25 | 10.25.131.1 – 10.25.131.126 | 10.25.131.127 |
| 8 | 10.25.131.128/25 | 10.25.131.129 – 10.25.131.254 | 10.25.131.255 |
| 9 | 10.25.132.0/25 | 10.25.132.1 – 10.25.132.126 | 10.25.132.127 |
| 10 | 10.25.132.128/25 | 10.25.132.129 – 10.25.132.254 | 10.25.132.255 |
| 11 | 10.25.133.0/25 | 10.25.133.1 – 10.25.133.126 | 10.25.133.127 |
| 12 | 10.25.133.128/25 | 10.25.133.129 – 10.25.133.254 | 10.25.133.255 |
| 13 | 10.25.134.0/25 | 10.25.134.1 – 10.25.134.126 | 10.25.134.127 |
| 14 | 10.25.134.128/25 | 10.25.134.129 – 10.25.134.254 | 10.25.134.255 |
| 15 | 10.25.135.0/25 | 10.25.135.1 – 10.25.135.126 | 10.25.135.127 |
| 16 | 10.25.135.128/25 | 10.25.135.129 – 10.25.135.254 | 10.25.135.255 |
| 17 | 10.25.136.0/25 | 10.25.136.1 – 10.25.136.126 | 10.25.136.127 |
| 18 | 10.25.136.128/25 | 10.25.136.129 – 10.25.136.254 | 10.25.136.255 |
| 19 | 10.25.137.0/25 | 10.25.137.1 – 10.25.137.126 | 10.25.137.127 |
| 20 | 10.25.137.128/25 | 10.25.137.129 – 10.25.137.254 | 10.25.137.255 |
| 21 | 10.25.138.0/25 | 10.25.138.1 – 10.25.138.126 | 10.25.138.127 |
| 22 | 10.25.138.128/25 | 10.25.138.129 – 10.25.138.254 | 10.25.138.255 |
| 23 | 10.25.139.0/25 | 10.25.139.1 – 10.25.139.126 | 10.25.139.127 |
| 24 | 10.25.139.128/25 | 10.25.139.129 – 10.25.139.254 | 10.25.139.255 |
| 25 | 10.25.140.0/25 | 10.25.140.1 – 10.25.140.126 | 10.25.140.127 |
| 26 | 10.25.140.128/25 | 10.25.140.129 – 10.25.140.254 | 10.25.140.255 |
| 27 | 10.25.141.0/25 | 10.25.141.1 – 10.25.141.126 | 10.25.141.127 |
| 28 | 10.25.141.128/25 | 10.25.141.129 – 10.25.141.254 | 10.25.141.255 |
| 29 | 10.25.142.0/25 | 10.25.142.1 – 10.25.142.126 | 10.25.142.127 |
| 30 | 10.25.142.128/25 | 10.25.142.129 – 10.25.142.254 | 10.25.142.255 |
| 31 | 10.25.143.0/25 | 10.25.143.1 – 10.25.143.126 | 10.25.143.127 |
| 32 | 10.25.143.128/25 | 10.25.143.129 – 10.25.143.254 | 10.25.143.255 |
| 33 | 10.25.144.0/25 | 10.25.144.1 – 10.25.144.126 | 10.25.144.127 |
| 34 | 10.25.144.128/25 | 10.25.144.129 – 10.25.144.254 | 10.25.144.255 |
| 35 | 10.25.145.0/25 | 10.25.145.1 – 10.25.145.126 | 10.25.145.127 |
| 36 | 10.25.145.128/25 | 10.25.145.129 – 10.25.145.254 | 10.25.145.255 |
| 37 | 10.25.146.0/25 | 10.25.146.1 – 10.25.146.126 | 10.25.146.127 |
| 38 | 10.25.146.128/25 | 10.25.146.129 – 10.25.146.254 | 10.25.146.255 |
| 39 | 10.25.147.0/25 | 10.25.147.1 – 10.25.147.126 | 10.25.147.127 |
| 40 | 10.25.147.128/25 | 10.25.147.129 – 10.25.147.254 | 10.25.147.255 |
| 41 | 10.25.148.0/25 | 10.25.148.1 – 10.25.148.126 | 10.25.148.127 |
| 42 | 10.25.148.128/25 | 10.25.148.129 – 10.25.148.254 | 10.25.148.255 |
| 43 | 10.25.149.0/25 | 10.25.149.1 – 10.25.149.126 | 10.25.149.127 |
| 44 | 10.25.149.128/25 | 10.25.149.129 – 10.25.149.254 | 10.25.149.255 |
| 45 | 10.25.150.0/25 | 10.25.150.1 – 10.25.150.126 | 10.25.150.127 |
| 46 | 10.25.150.128/25 | 10.25.150.129 – 10.25.150.254 | 10.25.150.255 |
| 47 | 10.25.151.0/25 | 10.25.151.1 – 10.25.151.126 | 10.25.151.127 |
| 48 | 10.25.151.128/25 | 10.25.151.129 – 10.25.151.254 | 10.25.151.255 |
| 49 | 10.25.152.0/25 | 10.25.152.1 – 10.25.152.126 | 10.25.152.127 |
| 50 | 10.25.152.128/25 | 10.25.152.129 – 10.25.152.254 | 10.25.152.255 |
| 51 | 10.25.153.0/25 | 10.25.153.1 – 10.25.153.126 | 10.25.153.127 |
| 52 | 10.25.153.128/25 | 10.25.153.129 – 10.25.153.254 | 10.25.153.255 |
| 53 | 10.25.154.0/25 | 10.25.154.1 – 10.25.154.126 | 10.25.154.127 |
| 54 | 10.25.154.128/25 | 10.25.154.129 – 10.25.154.254 | 10.25.154.255 |
| 55 | 10.25.155.0/25 | 10.25.155.1 – 10.25.155.126 | 10.25.155.127 |
| 56 | 10.25.155.128/25 | 10.25.155.129 – 10.25.155.254 | 10.25.155.255 |
| 57 | 10.25.156.0/25 | 10.25.156.1 – 10.25.156.126 | 10.25.156.127 |
| 58 | 10.25.156.128/25 | 10.25.156.129 – 10.25.156.254 | 10.25.156.255 |
| 59 | 10.25.157.0/25 | 10.25.157.1 – 10.25.157.126 | 10.25.157.127 |
| 60 | 10.25.157.128/25 | 10.25.157.129 – 10.25.157.254 | 10.25.157.255 |
| 61 | 10.25.158.0/25 | 10.25.158.1 – 10.25.158.126 | 10.25.158.127 |
| 62 | 10.25.158.128/25 | 10.25.158.129 – 10.25.158.254 | 10.25.158.255 |
| 63 | 10.25.159.0/25 | 10.25.159.1 – 10.25.159.126 | 10.25.159.127 |
| 64 | 10.25.159.128/25 | 10.25.159.129 – 10.25.159.254 | 10.25.159.255 |
| 65 | 10.25.160.0/25 | 10.25.160.1 – 10.25.160.126 | 10.25.160.127 |
| 66 | 10.25.160.128/25 | 10.25.160.129 – 10.25.160.254 | 10.25.160.255 |
| 67 | 10.25.161.0/25 | 10.25.161.1 – 10.25.161.126 | 10.25.161.127 |
| 68 | 10.25.161.128/25 | 10.25.161.129 – 10.25.161.254 | 10.25.161.255 |
| 69 | 10.25.162.0/25 | 10.25.162.1 – 10.25.162.126 | 10.25.162.127 |
| 70 | 10.25.162.128/25 | 10.25.162.129 – 10.25.162.254 | 10.25.162.255 |
| 71 | 10.25.163.0/25 | 10.25.163.1 – 10.25.163.126 | 10.25.163.127 |
| 72 | 10.25.163.128/25 | 10.25.163.129 – 10.25.163.254 | 10.25.163.255 |
| 73 | 10.25.164.0/25 | 10.25.164.1 – 10.25.164.126 | 10.25.164.127 |
| 74 | 10.25.164.128/25 | 10.25.164.129 – 10.25.164.254 | 10.25.164.255 |
| 75 | 10.25.165.0/25 | 10.25.165.1 – 10.25.165.126 | 10.25.165.127 |
| 76 | 10.25.165.128/25 | 10.25.165.129 – 10.25.165.254 | 10.25.165.255 |
| 77 | 10.25.166.0/25 | 10.25.166.1 – 10.25.166.126 | 10.25.166.127 |
| 78 | 10.25.166.128/25 | 10.25.166.129 – 10.25.166.254 | 10.25.166.255 |
| 79 | 10.25.167.0/25 | 10.25.167.1 – 10.25.167.126 | 10.25.167.127 |
| 80 | 10.25.167.128/25 | 10.25.167.129 – 10.25.167.254 | 10.25.167.255 |
| 81 | 10.25.168.0/25 | 10.25.168.1 – 10.25.168.126 | 10.25.168.127 |
| 82 | 10.25.168.128/25 | 10.25.168.129 – 10.25.168.254 | 10.25.168.255 |
| 83 | 10.25.169.0/25 | 10.25.169.1 – 10.25.169.126 | 10.25.169.127 |
| 84 | 10.25.169.128/25 | 10.25.169.129 – 10.25.169.254 | 10.25.169.255 |
| 85 | 10.25.170.0/25 | 10.25.170.1 – 10.25.170.126 | 10.25.170.127 |
| 86 | 10.25.170.128/25 | 10.25.170.129 – 10.25.170.254 | 10.25.170.255 |
| 87 | 10.25.171.0/25 | 10.25.171.1 – 10.25.171.126 | 10.25.171.127 |
| 88 | 10.25.171.128/25 | 10.25.171.129 – 10.25.171.254 | 10.25.171.255 |
| 89 | 10.25.172.0/25 | 10.25.172.1 – 10.25.172.126 | 10.25.172.127 |
| 90 | 10.25.172.128/25 | 10.25.172.129 – 10.25.172.254 | 10.25.172.255 |
| 91 | 10.25.173.0/25 | 10.25.173.1 – 10.25.173.126 | 10.25.173.127 |
| 92 | 10.25.173.128/25 | 10.25.173.129 – 10.25.173.254 | 10.25.173.255 |
| 93 | 10.25.174.0/25 | 10.25.174.1 – 10.25.174.126 | 10.25.174.127 |
| 94 | 10.25.174.128/25 | 10.25.174.129 – 10.25.174.254 | 10.25.174.255 |
| 95 | 10.25.175.0/25 | 10.25.175.1 – 10.25.175.126 | 10.25.175.127 |
| 96 | 10.25.175.128/25 | 10.25.175.129 – 10.25.175.254 | 10.25.175.255 |
| 97 | 10.25.176.0/25 | 10.25.176.1 – 10.25.176.126 | 10.25.176.127 |
| 98 | 10.25.176.128/25 | 10.25.176.129 – 10.25.176.254 | 10.25.176.255 |
| 99 | 10.25.177.0/25 | 10.25.177.1 – 10.25.177.126 | 10.25.177.127 |
| 100 | 10.25.177.128/25 | 10.25.177.129 – 10.25.177.254 | 10.25.177.255 |
| 101 | 10.25.178.0/25 | 10.25.178.1 – 10.25.178.126 | 10.25.178.127 |
| 102 | 10.25.178.128/25 | 10.25.178.129 – 10.25.178.254 | 10.25.178.255 |
| 103 | 10.25.179.0/25 | 10.25.179.1 – 10.25.179.126 | 10.25.179.127 |
| 104 | 10.25.179.128/25 | 10.25.179.129 – 10.25.179.254 | 10.25.179.255 |
| 105 | 10.25.180.0/25 | 10.25.180.1 – 10.25.180.126 | 10.25.180.127 |
| 106 | 10.25.180.128/25 | 10.25.180.129 – 10.25.180.254 | 10.25.180.255 |
| 107 | 10.25.181.0/25 | 10.25.181.1 – 10.25.181.126 | 10.25.181.127 |
| 108 | 10.25.181.128/25 | 10.25.181.129 – 10.25.181.254 | 10.25.181.255 |
| 109 | 10.25.182.0/25 | 10.25.182.1 – 10.25.182.126 | 10.25.182.127 |
| 110 | 10.25.182.128/25 | 10.25.182.129 – 10.25.182.254 | 10.25.182.255 |
| 111 | 10.25.183.0/25 | 10.25.183.1 – 10.25.183.126 | 10.25.183.127 |
| 112 | 10.25.183.128/25 | 10.25.183.129 – 10.25.183.254 | 10.25.183.255 |
| 113 | 10.25.184.0/25 | 10.25.184.1 – 10.25.184.126 | 10.25.184.127 |
| 114 | 10.25.184.128/25 | 10.25.184.129 – 10.25.184.254 | 10.25.184.255 |
| 115 | 10.25.185.0/25 | 10.25.185.1 – 10.25.185.126 | 10.25.185.127 |
| 116 | 10.25.185.128/25 | 10.25.185.129 – 10.25.185.254 | 10.25.185.255 |
| 117 | 10.25.186.0/25 | 10.25.186.1 – 10.25.186.126 | 10.25.186.127 |
| 118 | 10.25.186.128/25 | 10.25.186.129 – 10.25.186.254 | 10.25.186.255 |
| 119 | 10.25.187.0/25 | 10.25.187.1 – 10.25.187.126 | 10.25.187.127 |
| 120 | 10.25.187.128/25 | 10.25.187.129 – 10.25.187.254 | 10.25.187.255 |
| 121 | 10.25.188.0/25 | 10.25.188.1 – 10.25.188.126 | 10.25.188.127 |
| 122 | 10.25.188.128/25 | 10.25.188.129 – 10.25.188.254 | 10.25.188.255 |
| 123 | 10.25.189.0/25 | 10.25.189.1 – 10.25.189.126 | 10.25.189.127 |
| 124 | 10.25.189.128/25 | 10.25.189.129 – 10.25.189.254 | 10.25.189.255 |
| 125 | 10.25.190.0/25 | 10.25.190.1 – 10.25.190.126 | 10.25.190.127 |
| 126 | 10.25.190.128/25 | 10.25.190.129 – 10.25.190.254 | 10.25.190.255 |
| 127 | 10.25.191.0/25 | 10.25.191.1 – 10.25.191.126 | 10.25.191.127 |
| 128 | 10.25.191.128/25 | 10.25.191.129 – 10.25.191.254 | 10.25.191.255 |
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.