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.
/21 split into /28 · 128 subnets
close ×| # | network | host range | broadcast |
|---|---|---|---|
| 1 | 10.7.224.0/28 | 10.7.224.1 – 10.7.224.14 | 10.7.224.15 |
| 2 | 10.7.224.16/28 | 10.7.224.17 – 10.7.224.30 | 10.7.224.31 |
| 3 | 10.7.224.32/28 | 10.7.224.33 – 10.7.224.46 | 10.7.224.47 |
| 4 | 10.7.224.48/28 | 10.7.224.49 – 10.7.224.62 | 10.7.224.63 |
| 5 | 10.7.224.64/28 | 10.7.224.65 – 10.7.224.78 | 10.7.224.79 |
| 6 | 10.7.224.80/28 | 10.7.224.81 – 10.7.224.94 | 10.7.224.95 |
| 7 | 10.7.224.96/28 | 10.7.224.97 – 10.7.224.110 | 10.7.224.111 |
| 8 | 10.7.224.112/28 | 10.7.224.113 – 10.7.224.126 | 10.7.224.127 |
| 9 | 10.7.224.128/28 | 10.7.224.129 – 10.7.224.142 | 10.7.224.143 |
| 10 | 10.7.224.144/28 | 10.7.224.145 – 10.7.224.158 | 10.7.224.159 |
| 11 | 10.7.224.160/28 | 10.7.224.161 – 10.7.224.174 | 10.7.224.175 |
| 12 | 10.7.224.176/28 | 10.7.224.177 – 10.7.224.190 | 10.7.224.191 |
| 13 | 10.7.224.192/28 | 10.7.224.193 – 10.7.224.206 | 10.7.224.207 |
| 14 | 10.7.224.208/28 | 10.7.224.209 – 10.7.224.222 | 10.7.224.223 |
| 15 | 10.7.224.224/28 | 10.7.224.225 – 10.7.224.238 | 10.7.224.239 |
| 16 | 10.7.224.240/28 | 10.7.224.241 – 10.7.224.254 | 10.7.224.255 |
| 17 | 10.7.225.0/28 | 10.7.225.1 – 10.7.225.14 | 10.7.225.15 |
| 18 | 10.7.225.16/28 | 10.7.225.17 – 10.7.225.30 | 10.7.225.31 |
| 19 | 10.7.225.32/28 | 10.7.225.33 – 10.7.225.46 | 10.7.225.47 |
| 20 | 10.7.225.48/28 | 10.7.225.49 – 10.7.225.62 | 10.7.225.63 |
| 21 | 10.7.225.64/28 | 10.7.225.65 – 10.7.225.78 | 10.7.225.79 |
| 22 | 10.7.225.80/28 | 10.7.225.81 – 10.7.225.94 | 10.7.225.95 |
| 23 | 10.7.225.96/28 | 10.7.225.97 – 10.7.225.110 | 10.7.225.111 |
| 24 | 10.7.225.112/28 | 10.7.225.113 – 10.7.225.126 | 10.7.225.127 |
| 25 | 10.7.225.128/28 | 10.7.225.129 – 10.7.225.142 | 10.7.225.143 |
| 26 | 10.7.225.144/28 | 10.7.225.145 – 10.7.225.158 | 10.7.225.159 |
| 27 | 10.7.225.160/28 | 10.7.225.161 – 10.7.225.174 | 10.7.225.175 |
| 28 | 10.7.225.176/28 | 10.7.225.177 – 10.7.225.190 | 10.7.225.191 |
| 29 | 10.7.225.192/28 | 10.7.225.193 – 10.7.225.206 | 10.7.225.207 |
| 30 | 10.7.225.208/28 | 10.7.225.209 – 10.7.225.222 | 10.7.225.223 |
| 31 | 10.7.225.224/28 | 10.7.225.225 – 10.7.225.238 | 10.7.225.239 |
| 32 | 10.7.225.240/28 | 10.7.225.241 – 10.7.225.254 | 10.7.225.255 |
| 33 | 10.7.226.0/28 | 10.7.226.1 – 10.7.226.14 | 10.7.226.15 |
| 34 | 10.7.226.16/28 | 10.7.226.17 – 10.7.226.30 | 10.7.226.31 |
| 35 | 10.7.226.32/28 | 10.7.226.33 – 10.7.226.46 | 10.7.226.47 |
| 36 | 10.7.226.48/28 | 10.7.226.49 – 10.7.226.62 | 10.7.226.63 |
| 37 | 10.7.226.64/28 | 10.7.226.65 – 10.7.226.78 | 10.7.226.79 |
| 38 | 10.7.226.80/28 | 10.7.226.81 – 10.7.226.94 | 10.7.226.95 |
| 39 | 10.7.226.96/28 | 10.7.226.97 – 10.7.226.110 | 10.7.226.111 |
| 40 | 10.7.226.112/28 | 10.7.226.113 – 10.7.226.126 | 10.7.226.127 |
| 41 | 10.7.226.128/28 | 10.7.226.129 – 10.7.226.142 | 10.7.226.143 |
| 42 | 10.7.226.144/28 | 10.7.226.145 – 10.7.226.158 | 10.7.226.159 |
| 43 | 10.7.226.160/28 | 10.7.226.161 – 10.7.226.174 | 10.7.226.175 |
| 44 | 10.7.226.176/28 | 10.7.226.177 – 10.7.226.190 | 10.7.226.191 |
| 45 | 10.7.226.192/28 | 10.7.226.193 – 10.7.226.206 | 10.7.226.207 |
| 46 | 10.7.226.208/28 | 10.7.226.209 – 10.7.226.222 | 10.7.226.223 |
| 47 | 10.7.226.224/28 | 10.7.226.225 – 10.7.226.238 | 10.7.226.239 |
| 48 | 10.7.226.240/28 | 10.7.226.241 – 10.7.226.254 | 10.7.226.255 |
| 49 | 10.7.227.0/28 | 10.7.227.1 – 10.7.227.14 | 10.7.227.15 |
| 50 | 10.7.227.16/28 | 10.7.227.17 – 10.7.227.30 | 10.7.227.31 |
| 51 | 10.7.227.32/28 | 10.7.227.33 – 10.7.227.46 | 10.7.227.47 |
| 52 | 10.7.227.48/28 | 10.7.227.49 – 10.7.227.62 | 10.7.227.63 |
| 53 | 10.7.227.64/28 | 10.7.227.65 – 10.7.227.78 | 10.7.227.79 |
| 54 | 10.7.227.80/28 | 10.7.227.81 – 10.7.227.94 | 10.7.227.95 |
| 55 | 10.7.227.96/28 | 10.7.227.97 – 10.7.227.110 | 10.7.227.111 |
| 56 | 10.7.227.112/28 | 10.7.227.113 – 10.7.227.126 | 10.7.227.127 |
| 57 | 10.7.227.128/28 | 10.7.227.129 – 10.7.227.142 | 10.7.227.143 |
| 58 | 10.7.227.144/28 | 10.7.227.145 – 10.7.227.158 | 10.7.227.159 |
| 59 | 10.7.227.160/28 | 10.7.227.161 – 10.7.227.174 | 10.7.227.175 |
| 60 | 10.7.227.176/28 | 10.7.227.177 – 10.7.227.190 | 10.7.227.191 |
| 61 | 10.7.227.192/28 | 10.7.227.193 – 10.7.227.206 | 10.7.227.207 |
| 62 | 10.7.227.208/28 | 10.7.227.209 – 10.7.227.222 | 10.7.227.223 |
| 63 | 10.7.227.224/28 | 10.7.227.225 – 10.7.227.238 | 10.7.227.239 |
| 64 | 10.7.227.240/28 | 10.7.227.241 – 10.7.227.254 | 10.7.227.255 |
| 65 | 10.7.228.0/28 | 10.7.228.1 – 10.7.228.14 | 10.7.228.15 |
| 66 | 10.7.228.16/28 | 10.7.228.17 – 10.7.228.30 | 10.7.228.31 |
| 67 | 10.7.228.32/28 | 10.7.228.33 – 10.7.228.46 | 10.7.228.47 |
| 68 | 10.7.228.48/28 | 10.7.228.49 – 10.7.228.62 | 10.7.228.63 |
| 69 | 10.7.228.64/28 | 10.7.228.65 – 10.7.228.78 | 10.7.228.79 |
| 70 | 10.7.228.80/28 | 10.7.228.81 – 10.7.228.94 | 10.7.228.95 |
| 71 | 10.7.228.96/28 | 10.7.228.97 – 10.7.228.110 | 10.7.228.111 |
| 72 | 10.7.228.112/28 | 10.7.228.113 – 10.7.228.126 | 10.7.228.127 |
| 73 | 10.7.228.128/28 | 10.7.228.129 – 10.7.228.142 | 10.7.228.143 |
| 74 | 10.7.228.144/28 | 10.7.228.145 – 10.7.228.158 | 10.7.228.159 |
| 75 | 10.7.228.160/28 | 10.7.228.161 – 10.7.228.174 | 10.7.228.175 |
| 76 | 10.7.228.176/28 | 10.7.228.177 – 10.7.228.190 | 10.7.228.191 |
| 77 | 10.7.228.192/28 | 10.7.228.193 – 10.7.228.206 | 10.7.228.207 |
| 78 | 10.7.228.208/28 | 10.7.228.209 – 10.7.228.222 | 10.7.228.223 |
| 79 | 10.7.228.224/28 | 10.7.228.225 – 10.7.228.238 | 10.7.228.239 |
| 80 | 10.7.228.240/28 | 10.7.228.241 – 10.7.228.254 | 10.7.228.255 |
| 81 | 10.7.229.0/28 | 10.7.229.1 – 10.7.229.14 | 10.7.229.15 |
| 82 | 10.7.229.16/28 | 10.7.229.17 – 10.7.229.30 | 10.7.229.31 |
| 83 | 10.7.229.32/28 | 10.7.229.33 – 10.7.229.46 | 10.7.229.47 |
| 84 | 10.7.229.48/28 | 10.7.229.49 – 10.7.229.62 | 10.7.229.63 |
| 85 | 10.7.229.64/28 | 10.7.229.65 – 10.7.229.78 | 10.7.229.79 |
| 86 | 10.7.229.80/28 | 10.7.229.81 – 10.7.229.94 | 10.7.229.95 |
| 87 | 10.7.229.96/28 | 10.7.229.97 – 10.7.229.110 | 10.7.229.111 |
| 88 | 10.7.229.112/28 | 10.7.229.113 – 10.7.229.126 | 10.7.229.127 |
| 89 | 10.7.229.128/28 | 10.7.229.129 – 10.7.229.142 | 10.7.229.143 |
| 90 | 10.7.229.144/28 | 10.7.229.145 – 10.7.229.158 | 10.7.229.159 |
| 91 | 10.7.229.160/28 | 10.7.229.161 – 10.7.229.174 | 10.7.229.175 |
| 92 | 10.7.229.176/28 | 10.7.229.177 – 10.7.229.190 | 10.7.229.191 |
| 93 | 10.7.229.192/28 | 10.7.229.193 – 10.7.229.206 | 10.7.229.207 |
| 94 | 10.7.229.208/28 | 10.7.229.209 – 10.7.229.222 | 10.7.229.223 |
| 95 | 10.7.229.224/28 | 10.7.229.225 – 10.7.229.238 | 10.7.229.239 |
| 96 | 10.7.229.240/28 | 10.7.229.241 – 10.7.229.254 | 10.7.229.255 |
| 97 | 10.7.230.0/28 | 10.7.230.1 – 10.7.230.14 | 10.7.230.15 |
| 98 | 10.7.230.16/28 | 10.7.230.17 – 10.7.230.30 | 10.7.230.31 |
| 99 | 10.7.230.32/28 | 10.7.230.33 – 10.7.230.46 | 10.7.230.47 |
| 100 | 10.7.230.48/28 | 10.7.230.49 – 10.7.230.62 | 10.7.230.63 |
| 101 | 10.7.230.64/28 | 10.7.230.65 – 10.7.230.78 | 10.7.230.79 |
| 102 | 10.7.230.80/28 | 10.7.230.81 – 10.7.230.94 | 10.7.230.95 |
| 103 | 10.7.230.96/28 | 10.7.230.97 – 10.7.230.110 | 10.7.230.111 |
| 104 | 10.7.230.112/28 | 10.7.230.113 – 10.7.230.126 | 10.7.230.127 |
| 105 | 10.7.230.128/28 | 10.7.230.129 – 10.7.230.142 | 10.7.230.143 |
| 106 | 10.7.230.144/28 | 10.7.230.145 – 10.7.230.158 | 10.7.230.159 |
| 107 | 10.7.230.160/28 | 10.7.230.161 – 10.7.230.174 | 10.7.230.175 |
| 108 | 10.7.230.176/28 | 10.7.230.177 – 10.7.230.190 | 10.7.230.191 |
| 109 | 10.7.230.192/28 | 10.7.230.193 – 10.7.230.206 | 10.7.230.207 |
| 110 | 10.7.230.208/28 | 10.7.230.209 – 10.7.230.222 | 10.7.230.223 |
| 111 | 10.7.230.224/28 | 10.7.230.225 – 10.7.230.238 | 10.7.230.239 |
| 112 | 10.7.230.240/28 | 10.7.230.241 – 10.7.230.254 | 10.7.230.255 |
| 113 | 10.7.231.0/28 | 10.7.231.1 – 10.7.231.14 | 10.7.231.15 |
| 114 | 10.7.231.16/28 | 10.7.231.17 – 10.7.231.30 | 10.7.231.31 |
| 115 | 10.7.231.32/28 | 10.7.231.33 – 10.7.231.46 | 10.7.231.47 |
| 116 | 10.7.231.48/28 | 10.7.231.49 – 10.7.231.62 | 10.7.231.63 |
| 117 | 10.7.231.64/28 | 10.7.231.65 – 10.7.231.78 | 10.7.231.79 |
| 118 | 10.7.231.80/28 | 10.7.231.81 – 10.7.231.94 | 10.7.231.95 |
| 119 | 10.7.231.96/28 | 10.7.231.97 – 10.7.231.110 | 10.7.231.111 |
| 120 | 10.7.231.112/28 | 10.7.231.113 – 10.7.231.126 | 10.7.231.127 |
| 121 | 10.7.231.128/28 | 10.7.231.129 – 10.7.231.142 | 10.7.231.143 |
| 122 | 10.7.231.144/28 | 10.7.231.145 – 10.7.231.158 | 10.7.231.159 |
| 123 | 10.7.231.160/28 | 10.7.231.161 – 10.7.231.174 | 10.7.231.175 |
| 124 | 10.7.231.176/28 | 10.7.231.177 – 10.7.231.190 | 10.7.231.191 |
| 125 | 10.7.231.192/28 | 10.7.231.193 – 10.7.231.206 | 10.7.231.207 |
| 126 | 10.7.231.208/28 | 10.7.231.209 – 10.7.231.222 | 10.7.231.223 |
| 127 | 10.7.231.224/28 | 10.7.231.225 – 10.7.231.238 | 10.7.231.239 |
| 128 | 10.7.231.240/28 | 10.7.231.241 – 10.7.231.254 | 10.7.231.255 |
IPv4 CIDR prefix table.
Click a prefix longer than your network to split it into subnets.
| prefix | subnet mask | addresses | hosts | in your /21 |
|---|---|---|---|---|
| /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 | 1 |
| /22 | 255.255.252.0 | 1,024 | 1,022 | 2 split → |
| /23 | 255.255.254.0 | 512 | 510 | 4 split → |
| /24 | 255.255.255.0 | 256 | 254 | 8 split → |
| /25 | 255.255.255.128 | 128 | 126 | 16 split → |
| /26 | 255.255.255.192 | 64 | 62 | 32 split → |
| /27 | 255.255.255.224 | 32 | 30 | 64 split → |
| /28 | 255.255.255.240 | 16 | 14 | 128 split → |
| /29 | 255.255.255.248 | 8 | 6 | 256 split → |
| /30 | 255.255.255.252 | 4 | 2 | 512 split → |
| /31 | 255.255.255.254 | 2 | 2 | 1,024 split → |
| /32 | 255.255.255.255 | 1 | 1 | 2,048 split → |
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.