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)10.166.80.0/20
network10.166.80.0/20
broadcast10.166.95.255
first host10.166.80.1
last host10.166.95.254
subnet mask255.255.240.0
wildcard0.0.15.255
addresses4,096
usable hosts4,094
classA
ipcalc 10.166.80.0/20
address00001010.10100110.01010000.00000000
subnet mask11111111.11111111.11110000.00000000
network00001010.10100110.01010000.00000000
broadcast00001010.10100110.01011111.11111111
green = network part, grey = host part
hex0x0aa65000
decimal178671616
reverse dns0.80.166.10.in-addr.arpa
ipv4-mapped::ffff:aa6:5000
/20 split into /27 · 128 subnets
close ×| # | network | host range | broadcast |
|---|---|---|---|
| 1 | 10.166.80.0/27 | 10.166.80.1 – 10.166.80.30 | 10.166.80.31 |
| 2 | 10.166.80.32/27 | 10.166.80.33 – 10.166.80.62 | 10.166.80.63 |
| 3 | 10.166.80.64/27 | 10.166.80.65 – 10.166.80.94 | 10.166.80.95 |
| 4 | 10.166.80.96/27 | 10.166.80.97 – 10.166.80.126 | 10.166.80.127 |
| 5 | 10.166.80.128/27 | 10.166.80.129 – 10.166.80.158 | 10.166.80.159 |
| 6 | 10.166.80.160/27 | 10.166.80.161 – 10.166.80.190 | 10.166.80.191 |
| 7 | 10.166.80.192/27 | 10.166.80.193 – 10.166.80.222 | 10.166.80.223 |
| 8 | 10.166.80.224/27 | 10.166.80.225 – 10.166.80.254 | 10.166.80.255 |
| 9 | 10.166.81.0/27 | 10.166.81.1 – 10.166.81.30 | 10.166.81.31 |
| 10 | 10.166.81.32/27 | 10.166.81.33 – 10.166.81.62 | 10.166.81.63 |
| 11 | 10.166.81.64/27 | 10.166.81.65 – 10.166.81.94 | 10.166.81.95 |
| 12 | 10.166.81.96/27 | 10.166.81.97 – 10.166.81.126 | 10.166.81.127 |
| 13 | 10.166.81.128/27 | 10.166.81.129 – 10.166.81.158 | 10.166.81.159 |
| 14 | 10.166.81.160/27 | 10.166.81.161 – 10.166.81.190 | 10.166.81.191 |
| 15 | 10.166.81.192/27 | 10.166.81.193 – 10.166.81.222 | 10.166.81.223 |
| 16 | 10.166.81.224/27 | 10.166.81.225 – 10.166.81.254 | 10.166.81.255 |
| 17 | 10.166.82.0/27 | 10.166.82.1 – 10.166.82.30 | 10.166.82.31 |
| 18 | 10.166.82.32/27 | 10.166.82.33 – 10.166.82.62 | 10.166.82.63 |
| 19 | 10.166.82.64/27 | 10.166.82.65 – 10.166.82.94 | 10.166.82.95 |
| 20 | 10.166.82.96/27 | 10.166.82.97 – 10.166.82.126 | 10.166.82.127 |
| 21 | 10.166.82.128/27 | 10.166.82.129 – 10.166.82.158 | 10.166.82.159 |
| 22 | 10.166.82.160/27 | 10.166.82.161 – 10.166.82.190 | 10.166.82.191 |
| 23 | 10.166.82.192/27 | 10.166.82.193 – 10.166.82.222 | 10.166.82.223 |
| 24 | 10.166.82.224/27 | 10.166.82.225 – 10.166.82.254 | 10.166.82.255 |
| 25 | 10.166.83.0/27 | 10.166.83.1 – 10.166.83.30 | 10.166.83.31 |
| 26 | 10.166.83.32/27 | 10.166.83.33 – 10.166.83.62 | 10.166.83.63 |
| 27 | 10.166.83.64/27 | 10.166.83.65 – 10.166.83.94 | 10.166.83.95 |
| 28 | 10.166.83.96/27 | 10.166.83.97 – 10.166.83.126 | 10.166.83.127 |
| 29 | 10.166.83.128/27 | 10.166.83.129 – 10.166.83.158 | 10.166.83.159 |
| 30 | 10.166.83.160/27 | 10.166.83.161 – 10.166.83.190 | 10.166.83.191 |
| 31 | 10.166.83.192/27 | 10.166.83.193 – 10.166.83.222 | 10.166.83.223 |
| 32 | 10.166.83.224/27 | 10.166.83.225 – 10.166.83.254 | 10.166.83.255 |
| 33 | 10.166.84.0/27 | 10.166.84.1 – 10.166.84.30 | 10.166.84.31 |
| 34 | 10.166.84.32/27 | 10.166.84.33 – 10.166.84.62 | 10.166.84.63 |
| 35 | 10.166.84.64/27 | 10.166.84.65 – 10.166.84.94 | 10.166.84.95 |
| 36 | 10.166.84.96/27 | 10.166.84.97 – 10.166.84.126 | 10.166.84.127 |
| 37 | 10.166.84.128/27 | 10.166.84.129 – 10.166.84.158 | 10.166.84.159 |
| 38 | 10.166.84.160/27 | 10.166.84.161 – 10.166.84.190 | 10.166.84.191 |
| 39 | 10.166.84.192/27 | 10.166.84.193 – 10.166.84.222 | 10.166.84.223 |
| 40 | 10.166.84.224/27 | 10.166.84.225 – 10.166.84.254 | 10.166.84.255 |
| 41 | 10.166.85.0/27 | 10.166.85.1 – 10.166.85.30 | 10.166.85.31 |
| 42 | 10.166.85.32/27 | 10.166.85.33 – 10.166.85.62 | 10.166.85.63 |
| 43 | 10.166.85.64/27 | 10.166.85.65 – 10.166.85.94 | 10.166.85.95 |
| 44 | 10.166.85.96/27 | 10.166.85.97 – 10.166.85.126 | 10.166.85.127 |
| 45 | 10.166.85.128/27 | 10.166.85.129 – 10.166.85.158 | 10.166.85.159 |
| 46 | 10.166.85.160/27 | 10.166.85.161 – 10.166.85.190 | 10.166.85.191 |
| 47 | 10.166.85.192/27 | 10.166.85.193 – 10.166.85.222 | 10.166.85.223 |
| 48 | 10.166.85.224/27 | 10.166.85.225 – 10.166.85.254 | 10.166.85.255 |
| 49 | 10.166.86.0/27 | 10.166.86.1 – 10.166.86.30 | 10.166.86.31 |
| 50 | 10.166.86.32/27 | 10.166.86.33 – 10.166.86.62 | 10.166.86.63 |
| 51 | 10.166.86.64/27 | 10.166.86.65 – 10.166.86.94 | 10.166.86.95 |
| 52 | 10.166.86.96/27 | 10.166.86.97 – 10.166.86.126 | 10.166.86.127 |
| 53 | 10.166.86.128/27 | 10.166.86.129 – 10.166.86.158 | 10.166.86.159 |
| 54 | 10.166.86.160/27 | 10.166.86.161 – 10.166.86.190 | 10.166.86.191 |
| 55 | 10.166.86.192/27 | 10.166.86.193 – 10.166.86.222 | 10.166.86.223 |
| 56 | 10.166.86.224/27 | 10.166.86.225 – 10.166.86.254 | 10.166.86.255 |
| 57 | 10.166.87.0/27 | 10.166.87.1 – 10.166.87.30 | 10.166.87.31 |
| 58 | 10.166.87.32/27 | 10.166.87.33 – 10.166.87.62 | 10.166.87.63 |
| 59 | 10.166.87.64/27 | 10.166.87.65 – 10.166.87.94 | 10.166.87.95 |
| 60 | 10.166.87.96/27 | 10.166.87.97 – 10.166.87.126 | 10.166.87.127 |
| 61 | 10.166.87.128/27 | 10.166.87.129 – 10.166.87.158 | 10.166.87.159 |
| 62 | 10.166.87.160/27 | 10.166.87.161 – 10.166.87.190 | 10.166.87.191 |
| 63 | 10.166.87.192/27 | 10.166.87.193 – 10.166.87.222 | 10.166.87.223 |
| 64 | 10.166.87.224/27 | 10.166.87.225 – 10.166.87.254 | 10.166.87.255 |
| 65 | 10.166.88.0/27 | 10.166.88.1 – 10.166.88.30 | 10.166.88.31 |
| 66 | 10.166.88.32/27 | 10.166.88.33 – 10.166.88.62 | 10.166.88.63 |
| 67 | 10.166.88.64/27 | 10.166.88.65 – 10.166.88.94 | 10.166.88.95 |
| 68 | 10.166.88.96/27 | 10.166.88.97 – 10.166.88.126 | 10.166.88.127 |
| 69 | 10.166.88.128/27 | 10.166.88.129 – 10.166.88.158 | 10.166.88.159 |
| 70 | 10.166.88.160/27 | 10.166.88.161 – 10.166.88.190 | 10.166.88.191 |
| 71 | 10.166.88.192/27 | 10.166.88.193 – 10.166.88.222 | 10.166.88.223 |
| 72 | 10.166.88.224/27 | 10.166.88.225 – 10.166.88.254 | 10.166.88.255 |
| 73 | 10.166.89.0/27 | 10.166.89.1 – 10.166.89.30 | 10.166.89.31 |
| 74 | 10.166.89.32/27 | 10.166.89.33 – 10.166.89.62 | 10.166.89.63 |
| 75 | 10.166.89.64/27 | 10.166.89.65 – 10.166.89.94 | 10.166.89.95 |
| 76 | 10.166.89.96/27 | 10.166.89.97 – 10.166.89.126 | 10.166.89.127 |
| 77 | 10.166.89.128/27 | 10.166.89.129 – 10.166.89.158 | 10.166.89.159 |
| 78 | 10.166.89.160/27 | 10.166.89.161 – 10.166.89.190 | 10.166.89.191 |
| 79 | 10.166.89.192/27 | 10.166.89.193 – 10.166.89.222 | 10.166.89.223 |
| 80 | 10.166.89.224/27 | 10.166.89.225 – 10.166.89.254 | 10.166.89.255 |
| 81 | 10.166.90.0/27 | 10.166.90.1 – 10.166.90.30 | 10.166.90.31 |
| 82 | 10.166.90.32/27 | 10.166.90.33 – 10.166.90.62 | 10.166.90.63 |
| 83 | 10.166.90.64/27 | 10.166.90.65 – 10.166.90.94 | 10.166.90.95 |
| 84 | 10.166.90.96/27 | 10.166.90.97 – 10.166.90.126 | 10.166.90.127 |
| 85 | 10.166.90.128/27 | 10.166.90.129 – 10.166.90.158 | 10.166.90.159 |
| 86 | 10.166.90.160/27 | 10.166.90.161 – 10.166.90.190 | 10.166.90.191 |
| 87 | 10.166.90.192/27 | 10.166.90.193 – 10.166.90.222 | 10.166.90.223 |
| 88 | 10.166.90.224/27 | 10.166.90.225 – 10.166.90.254 | 10.166.90.255 |
| 89 | 10.166.91.0/27 | 10.166.91.1 – 10.166.91.30 | 10.166.91.31 |
| 90 | 10.166.91.32/27 | 10.166.91.33 – 10.166.91.62 | 10.166.91.63 |
| 91 | 10.166.91.64/27 | 10.166.91.65 – 10.166.91.94 | 10.166.91.95 |
| 92 | 10.166.91.96/27 | 10.166.91.97 – 10.166.91.126 | 10.166.91.127 |
| 93 | 10.166.91.128/27 | 10.166.91.129 – 10.166.91.158 | 10.166.91.159 |
| 94 | 10.166.91.160/27 | 10.166.91.161 – 10.166.91.190 | 10.166.91.191 |
| 95 | 10.166.91.192/27 | 10.166.91.193 – 10.166.91.222 | 10.166.91.223 |
| 96 | 10.166.91.224/27 | 10.166.91.225 – 10.166.91.254 | 10.166.91.255 |
| 97 | 10.166.92.0/27 | 10.166.92.1 – 10.166.92.30 | 10.166.92.31 |
| 98 | 10.166.92.32/27 | 10.166.92.33 – 10.166.92.62 | 10.166.92.63 |
| 99 | 10.166.92.64/27 | 10.166.92.65 – 10.166.92.94 | 10.166.92.95 |
| 100 | 10.166.92.96/27 | 10.166.92.97 – 10.166.92.126 | 10.166.92.127 |
| 101 | 10.166.92.128/27 | 10.166.92.129 – 10.166.92.158 | 10.166.92.159 |
| 102 | 10.166.92.160/27 | 10.166.92.161 – 10.166.92.190 | 10.166.92.191 |
| 103 | 10.166.92.192/27 | 10.166.92.193 – 10.166.92.222 | 10.166.92.223 |
| 104 | 10.166.92.224/27 | 10.166.92.225 – 10.166.92.254 | 10.166.92.255 |
| 105 | 10.166.93.0/27 | 10.166.93.1 – 10.166.93.30 | 10.166.93.31 |
| 106 | 10.166.93.32/27 | 10.166.93.33 – 10.166.93.62 | 10.166.93.63 |
| 107 | 10.166.93.64/27 | 10.166.93.65 – 10.166.93.94 | 10.166.93.95 |
| 108 | 10.166.93.96/27 | 10.166.93.97 – 10.166.93.126 | 10.166.93.127 |
| 109 | 10.166.93.128/27 | 10.166.93.129 – 10.166.93.158 | 10.166.93.159 |
| 110 | 10.166.93.160/27 | 10.166.93.161 – 10.166.93.190 | 10.166.93.191 |
| 111 | 10.166.93.192/27 | 10.166.93.193 – 10.166.93.222 | 10.166.93.223 |
| 112 | 10.166.93.224/27 | 10.166.93.225 – 10.166.93.254 | 10.166.93.255 |
| 113 | 10.166.94.0/27 | 10.166.94.1 – 10.166.94.30 | 10.166.94.31 |
| 114 | 10.166.94.32/27 | 10.166.94.33 – 10.166.94.62 | 10.166.94.63 |
| 115 | 10.166.94.64/27 | 10.166.94.65 – 10.166.94.94 | 10.166.94.95 |
| 116 | 10.166.94.96/27 | 10.166.94.97 – 10.166.94.126 | 10.166.94.127 |
| 117 | 10.166.94.128/27 | 10.166.94.129 – 10.166.94.158 | 10.166.94.159 |
| 118 | 10.166.94.160/27 | 10.166.94.161 – 10.166.94.190 | 10.166.94.191 |
| 119 | 10.166.94.192/27 | 10.166.94.193 – 10.166.94.222 | 10.166.94.223 |
| 120 | 10.166.94.224/27 | 10.166.94.225 – 10.166.94.254 | 10.166.94.255 |
| 121 | 10.166.95.0/27 | 10.166.95.1 – 10.166.95.30 | 10.166.95.31 |
| 122 | 10.166.95.32/27 | 10.166.95.33 – 10.166.95.62 | 10.166.95.63 |
| 123 | 10.166.95.64/27 | 10.166.95.65 – 10.166.95.94 | 10.166.95.95 |
| 124 | 10.166.95.96/27 | 10.166.95.97 – 10.166.95.126 | 10.166.95.127 |
| 125 | 10.166.95.128/27 | 10.166.95.129 – 10.166.95.158 | 10.166.95.159 |
| 126 | 10.166.95.160/27 | 10.166.95.161 – 10.166.95.190 | 10.166.95.191 |
| 127 | 10.166.95.192/27 | 10.166.95.193 – 10.166.95.222 | 10.166.95.223 |
| 128 | 10.166.95.224/27 | 10.166.95.225 – 10.166.95.254 | 10.166.95.255 |
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 /20 |
|---|---|---|---|---|
| /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 | 1 |
| /21 | 255.255.248.0 | 2,048 | 2,046 | 2 split → |
| /22 | 255.255.252.0 | 1,024 | 1,022 | 4 split → |
| /23 | 255.255.254.0 | 512 | 510 | 8 split → |
| /24 | 255.255.255.0 | 256 | 254 | 16 split → |
| /25 | 255.255.255.128 | 128 | 126 | 32 split → |
| /26 | 255.255.255.192 | 64 | 62 | 64 split → |
| /27 | 255.255.255.224 | 32 | 30 | 128 split → |
| /28 | 255.255.255.240 | 16 | 14 | 256 split → |
| /29 | 255.255.255.248 | 8 | 6 | 512 split → |
| /30 | 255.255.255.252 | 4 | 2 | 1,024 split → |
| /31 | 255.255.255.254 | 2 | 2 | 2,048 split → |
| /32 | 255.255.255.255 | 1 | 1 | 4,096 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.