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)172.16.12.0/25
network172.16.12.0/25
broadcast172.16.12.127
first host172.16.12.1
last host172.16.12.126
subnet mask255.255.255.128
wildcard0.0.0.127
addresses128
usable hosts126
classB
ipcalc 172.16.12.0/25
address10101100.00010000.00001100.00000000
subnet mask11111111.11111111.11111111.10000000
network10101100.00010000.00001100.00000000
broadcast10101100.00010000.00001100.01111111
green = network part, grey = host part
hex0xac100c00
decimal2886732800
reverse dns0.12.16.172.in-addr.arpa
ipv4-mapped::ffff:ac10:c00
/25 split into /32 · 128 subnets
close ×| # | network | host range | broadcast |
|---|---|---|---|
| 1 | 172.16.12.0/32 | 172.16.12.0 – 172.16.12.0 | 172.16.12.0 |
| 2 | 172.16.12.1/32 | 172.16.12.1 – 172.16.12.1 | 172.16.12.1 |
| 3 | 172.16.12.2/32 | 172.16.12.2 – 172.16.12.2 | 172.16.12.2 |
| 4 | 172.16.12.3/32 | 172.16.12.3 – 172.16.12.3 | 172.16.12.3 |
| 5 | 172.16.12.4/32 | 172.16.12.4 – 172.16.12.4 | 172.16.12.4 |
| 6 | 172.16.12.5/32 | 172.16.12.5 – 172.16.12.5 | 172.16.12.5 |
| 7 | 172.16.12.6/32 | 172.16.12.6 – 172.16.12.6 | 172.16.12.6 |
| 8 | 172.16.12.7/32 | 172.16.12.7 – 172.16.12.7 | 172.16.12.7 |
| 9 | 172.16.12.8/32 | 172.16.12.8 – 172.16.12.8 | 172.16.12.8 |
| 10 | 172.16.12.9/32 | 172.16.12.9 – 172.16.12.9 | 172.16.12.9 |
| 11 | 172.16.12.10/32 | 172.16.12.10 – 172.16.12.10 | 172.16.12.10 |
| 12 | 172.16.12.11/32 | 172.16.12.11 – 172.16.12.11 | 172.16.12.11 |
| 13 | 172.16.12.12/32 | 172.16.12.12 – 172.16.12.12 | 172.16.12.12 |
| 14 | 172.16.12.13/32 | 172.16.12.13 – 172.16.12.13 | 172.16.12.13 |
| 15 | 172.16.12.14/32 | 172.16.12.14 – 172.16.12.14 | 172.16.12.14 |
| 16 | 172.16.12.15/32 | 172.16.12.15 – 172.16.12.15 | 172.16.12.15 |
| 17 | 172.16.12.16/32 | 172.16.12.16 – 172.16.12.16 | 172.16.12.16 |
| 18 | 172.16.12.17/32 | 172.16.12.17 – 172.16.12.17 | 172.16.12.17 |
| 19 | 172.16.12.18/32 | 172.16.12.18 – 172.16.12.18 | 172.16.12.18 |
| 20 | 172.16.12.19/32 | 172.16.12.19 – 172.16.12.19 | 172.16.12.19 |
| 21 | 172.16.12.20/32 | 172.16.12.20 – 172.16.12.20 | 172.16.12.20 |
| 22 | 172.16.12.21/32 | 172.16.12.21 – 172.16.12.21 | 172.16.12.21 |
| 23 | 172.16.12.22/32 | 172.16.12.22 – 172.16.12.22 | 172.16.12.22 |
| 24 | 172.16.12.23/32 | 172.16.12.23 – 172.16.12.23 | 172.16.12.23 |
| 25 | 172.16.12.24/32 | 172.16.12.24 – 172.16.12.24 | 172.16.12.24 |
| 26 | 172.16.12.25/32 | 172.16.12.25 – 172.16.12.25 | 172.16.12.25 |
| 27 | 172.16.12.26/32 | 172.16.12.26 – 172.16.12.26 | 172.16.12.26 |
| 28 | 172.16.12.27/32 | 172.16.12.27 – 172.16.12.27 | 172.16.12.27 |
| 29 | 172.16.12.28/32 | 172.16.12.28 – 172.16.12.28 | 172.16.12.28 |
| 30 | 172.16.12.29/32 | 172.16.12.29 – 172.16.12.29 | 172.16.12.29 |
| 31 | 172.16.12.30/32 | 172.16.12.30 – 172.16.12.30 | 172.16.12.30 |
| 32 | 172.16.12.31/32 | 172.16.12.31 – 172.16.12.31 | 172.16.12.31 |
| 33 | 172.16.12.32/32 | 172.16.12.32 – 172.16.12.32 | 172.16.12.32 |
| 34 | 172.16.12.33/32 | 172.16.12.33 – 172.16.12.33 | 172.16.12.33 |
| 35 | 172.16.12.34/32 | 172.16.12.34 – 172.16.12.34 | 172.16.12.34 |
| 36 | 172.16.12.35/32 | 172.16.12.35 – 172.16.12.35 | 172.16.12.35 |
| 37 | 172.16.12.36/32 | 172.16.12.36 – 172.16.12.36 | 172.16.12.36 |
| 38 | 172.16.12.37/32 | 172.16.12.37 – 172.16.12.37 | 172.16.12.37 |
| 39 | 172.16.12.38/32 | 172.16.12.38 – 172.16.12.38 | 172.16.12.38 |
| 40 | 172.16.12.39/32 | 172.16.12.39 – 172.16.12.39 | 172.16.12.39 |
| 41 | 172.16.12.40/32 | 172.16.12.40 – 172.16.12.40 | 172.16.12.40 |
| 42 | 172.16.12.41/32 | 172.16.12.41 – 172.16.12.41 | 172.16.12.41 |
| 43 | 172.16.12.42/32 | 172.16.12.42 – 172.16.12.42 | 172.16.12.42 |
| 44 | 172.16.12.43/32 | 172.16.12.43 – 172.16.12.43 | 172.16.12.43 |
| 45 | 172.16.12.44/32 | 172.16.12.44 – 172.16.12.44 | 172.16.12.44 |
| 46 | 172.16.12.45/32 | 172.16.12.45 – 172.16.12.45 | 172.16.12.45 |
| 47 | 172.16.12.46/32 | 172.16.12.46 – 172.16.12.46 | 172.16.12.46 |
| 48 | 172.16.12.47/32 | 172.16.12.47 – 172.16.12.47 | 172.16.12.47 |
| 49 | 172.16.12.48/32 | 172.16.12.48 – 172.16.12.48 | 172.16.12.48 |
| 50 | 172.16.12.49/32 | 172.16.12.49 – 172.16.12.49 | 172.16.12.49 |
| 51 | 172.16.12.50/32 | 172.16.12.50 – 172.16.12.50 | 172.16.12.50 |
| 52 | 172.16.12.51/32 | 172.16.12.51 – 172.16.12.51 | 172.16.12.51 |
| 53 | 172.16.12.52/32 | 172.16.12.52 – 172.16.12.52 | 172.16.12.52 |
| 54 | 172.16.12.53/32 | 172.16.12.53 – 172.16.12.53 | 172.16.12.53 |
| 55 | 172.16.12.54/32 | 172.16.12.54 – 172.16.12.54 | 172.16.12.54 |
| 56 | 172.16.12.55/32 | 172.16.12.55 – 172.16.12.55 | 172.16.12.55 |
| 57 | 172.16.12.56/32 | 172.16.12.56 – 172.16.12.56 | 172.16.12.56 |
| 58 | 172.16.12.57/32 | 172.16.12.57 – 172.16.12.57 | 172.16.12.57 |
| 59 | 172.16.12.58/32 | 172.16.12.58 – 172.16.12.58 | 172.16.12.58 |
| 60 | 172.16.12.59/32 | 172.16.12.59 – 172.16.12.59 | 172.16.12.59 |
| 61 | 172.16.12.60/32 | 172.16.12.60 – 172.16.12.60 | 172.16.12.60 |
| 62 | 172.16.12.61/32 | 172.16.12.61 – 172.16.12.61 | 172.16.12.61 |
| 63 | 172.16.12.62/32 | 172.16.12.62 – 172.16.12.62 | 172.16.12.62 |
| 64 | 172.16.12.63/32 | 172.16.12.63 – 172.16.12.63 | 172.16.12.63 |
| 65 | 172.16.12.64/32 | 172.16.12.64 – 172.16.12.64 | 172.16.12.64 |
| 66 | 172.16.12.65/32 | 172.16.12.65 – 172.16.12.65 | 172.16.12.65 |
| 67 | 172.16.12.66/32 | 172.16.12.66 – 172.16.12.66 | 172.16.12.66 |
| 68 | 172.16.12.67/32 | 172.16.12.67 – 172.16.12.67 | 172.16.12.67 |
| 69 | 172.16.12.68/32 | 172.16.12.68 – 172.16.12.68 | 172.16.12.68 |
| 70 | 172.16.12.69/32 | 172.16.12.69 – 172.16.12.69 | 172.16.12.69 |
| 71 | 172.16.12.70/32 | 172.16.12.70 – 172.16.12.70 | 172.16.12.70 |
| 72 | 172.16.12.71/32 | 172.16.12.71 – 172.16.12.71 | 172.16.12.71 |
| 73 | 172.16.12.72/32 | 172.16.12.72 – 172.16.12.72 | 172.16.12.72 |
| 74 | 172.16.12.73/32 | 172.16.12.73 – 172.16.12.73 | 172.16.12.73 |
| 75 | 172.16.12.74/32 | 172.16.12.74 – 172.16.12.74 | 172.16.12.74 |
| 76 | 172.16.12.75/32 | 172.16.12.75 – 172.16.12.75 | 172.16.12.75 |
| 77 | 172.16.12.76/32 | 172.16.12.76 – 172.16.12.76 | 172.16.12.76 |
| 78 | 172.16.12.77/32 | 172.16.12.77 – 172.16.12.77 | 172.16.12.77 |
| 79 | 172.16.12.78/32 | 172.16.12.78 – 172.16.12.78 | 172.16.12.78 |
| 80 | 172.16.12.79/32 | 172.16.12.79 – 172.16.12.79 | 172.16.12.79 |
| 81 | 172.16.12.80/32 | 172.16.12.80 – 172.16.12.80 | 172.16.12.80 |
| 82 | 172.16.12.81/32 | 172.16.12.81 – 172.16.12.81 | 172.16.12.81 |
| 83 | 172.16.12.82/32 | 172.16.12.82 – 172.16.12.82 | 172.16.12.82 |
| 84 | 172.16.12.83/32 | 172.16.12.83 – 172.16.12.83 | 172.16.12.83 |
| 85 | 172.16.12.84/32 | 172.16.12.84 – 172.16.12.84 | 172.16.12.84 |
| 86 | 172.16.12.85/32 | 172.16.12.85 – 172.16.12.85 | 172.16.12.85 |
| 87 | 172.16.12.86/32 | 172.16.12.86 – 172.16.12.86 | 172.16.12.86 |
| 88 | 172.16.12.87/32 | 172.16.12.87 – 172.16.12.87 | 172.16.12.87 |
| 89 | 172.16.12.88/32 | 172.16.12.88 – 172.16.12.88 | 172.16.12.88 |
| 90 | 172.16.12.89/32 | 172.16.12.89 – 172.16.12.89 | 172.16.12.89 |
| 91 | 172.16.12.90/32 | 172.16.12.90 – 172.16.12.90 | 172.16.12.90 |
| 92 | 172.16.12.91/32 | 172.16.12.91 – 172.16.12.91 | 172.16.12.91 |
| 93 | 172.16.12.92/32 | 172.16.12.92 – 172.16.12.92 | 172.16.12.92 |
| 94 | 172.16.12.93/32 | 172.16.12.93 – 172.16.12.93 | 172.16.12.93 |
| 95 | 172.16.12.94/32 | 172.16.12.94 – 172.16.12.94 | 172.16.12.94 |
| 96 | 172.16.12.95/32 | 172.16.12.95 – 172.16.12.95 | 172.16.12.95 |
| 97 | 172.16.12.96/32 | 172.16.12.96 – 172.16.12.96 | 172.16.12.96 |
| 98 | 172.16.12.97/32 | 172.16.12.97 – 172.16.12.97 | 172.16.12.97 |
| 99 | 172.16.12.98/32 | 172.16.12.98 – 172.16.12.98 | 172.16.12.98 |
| 100 | 172.16.12.99/32 | 172.16.12.99 – 172.16.12.99 | 172.16.12.99 |
| 101 | 172.16.12.100/32 | 172.16.12.100 – 172.16.12.100 | 172.16.12.100 |
| 102 | 172.16.12.101/32 | 172.16.12.101 – 172.16.12.101 | 172.16.12.101 |
| 103 | 172.16.12.102/32 | 172.16.12.102 – 172.16.12.102 | 172.16.12.102 |
| 104 | 172.16.12.103/32 | 172.16.12.103 – 172.16.12.103 | 172.16.12.103 |
| 105 | 172.16.12.104/32 | 172.16.12.104 – 172.16.12.104 | 172.16.12.104 |
| 106 | 172.16.12.105/32 | 172.16.12.105 – 172.16.12.105 | 172.16.12.105 |
| 107 | 172.16.12.106/32 | 172.16.12.106 – 172.16.12.106 | 172.16.12.106 |
| 108 | 172.16.12.107/32 | 172.16.12.107 – 172.16.12.107 | 172.16.12.107 |
| 109 | 172.16.12.108/32 | 172.16.12.108 – 172.16.12.108 | 172.16.12.108 |
| 110 | 172.16.12.109/32 | 172.16.12.109 – 172.16.12.109 | 172.16.12.109 |
| 111 | 172.16.12.110/32 | 172.16.12.110 – 172.16.12.110 | 172.16.12.110 |
| 112 | 172.16.12.111/32 | 172.16.12.111 – 172.16.12.111 | 172.16.12.111 |
| 113 | 172.16.12.112/32 | 172.16.12.112 – 172.16.12.112 | 172.16.12.112 |
| 114 | 172.16.12.113/32 | 172.16.12.113 – 172.16.12.113 | 172.16.12.113 |
| 115 | 172.16.12.114/32 | 172.16.12.114 – 172.16.12.114 | 172.16.12.114 |
| 116 | 172.16.12.115/32 | 172.16.12.115 – 172.16.12.115 | 172.16.12.115 |
| 117 | 172.16.12.116/32 | 172.16.12.116 – 172.16.12.116 | 172.16.12.116 |
| 118 | 172.16.12.117/32 | 172.16.12.117 – 172.16.12.117 | 172.16.12.117 |
| 119 | 172.16.12.118/32 | 172.16.12.118 – 172.16.12.118 | 172.16.12.118 |
| 120 | 172.16.12.119/32 | 172.16.12.119 – 172.16.12.119 | 172.16.12.119 |
| 121 | 172.16.12.120/32 | 172.16.12.120 – 172.16.12.120 | 172.16.12.120 |
| 122 | 172.16.12.121/32 | 172.16.12.121 – 172.16.12.121 | 172.16.12.121 |
| 123 | 172.16.12.122/32 | 172.16.12.122 – 172.16.12.122 | 172.16.12.122 |
| 124 | 172.16.12.123/32 | 172.16.12.123 – 172.16.12.123 | 172.16.12.123 |
| 125 | 172.16.12.124/32 | 172.16.12.124 – 172.16.12.124 | 172.16.12.124 |
| 126 | 172.16.12.125/32 | 172.16.12.125 – 172.16.12.125 | 172.16.12.125 |
| 127 | 172.16.12.126/32 | 172.16.12.126 – 172.16.12.126 | 172.16.12.126 |
| 128 | 172.16.12.127/32 | 172.16.12.127 – 172.16.12.127 | 172.16.12.127 |
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 /25 |
|---|---|---|---|---|
| /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 | - |
| /19 | 255.255.224.0 | 8,192 | 8,190 | - |
| /20 | 255.255.240.0 | 4,096 | 4,094 | - |
| /21 | 255.255.248.0 | 2,048 | 2,046 | - |
| /22 | 255.255.252.0 | 1,024 | 1,022 | - |
| /23 | 255.255.254.0 | 512 | 510 | - |
| /24 | 255.255.255.0 | 256 | 254 | - |
| /25 | 255.255.255.128 | 128 | 126 | 1 |
| /26 | 255.255.255.192 | 64 | 62 | 2 split → |
| /27 | 255.255.255.224 | 32 | 30 | 4 split → |
| /28 | 255.255.255.240 | 16 | 14 | 8 split → |
| /29 | 255.255.255.248 | 8 | 6 | 16 split → |
| /30 | 255.255.255.252 | 4 | 2 | 32 split → |
| /31 | 255.255.255.254 | 2 | 2 | 64 split → |
| /32 | 255.255.255.255 | 1 | 1 | 128 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.