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)172.16.12.0/24
network172.16.12.0/24
broadcast172.16.12.255
first host172.16.12.1
last host172.16.12.254
subnet mask255.255.255.0
wildcard0.0.0.255
addresses256
usable hosts254
classB
ipcalc 172.16.12.0/24
address10101100.00010000.00001100.00000000
subnet mask11111111.11111111.11111111.00000000
network10101100.00010000.00001100.00000000
broadcast10101100.00010000.00001100.11111111
green = network part, grey = host part
hex0xac100c00
decimal2886732800
reverse dns0.12.16.172.in-addr.arpa
ipv4-mapped::ffff:ac10:c00
/24 split into /31 · 128 subnets
close ×| # | network | host range | broadcast |
|---|---|---|---|
| 1 | 172.16.12.0/31 | 172.16.12.0 – 172.16.12.1 | 172.16.12.1 |
| 2 | 172.16.12.2/31 | 172.16.12.2 – 172.16.12.3 | 172.16.12.3 |
| 3 | 172.16.12.4/31 | 172.16.12.4 – 172.16.12.5 | 172.16.12.5 |
| 4 | 172.16.12.6/31 | 172.16.12.6 – 172.16.12.7 | 172.16.12.7 |
| 5 | 172.16.12.8/31 | 172.16.12.8 – 172.16.12.9 | 172.16.12.9 |
| 6 | 172.16.12.10/31 | 172.16.12.10 – 172.16.12.11 | 172.16.12.11 |
| 7 | 172.16.12.12/31 | 172.16.12.12 – 172.16.12.13 | 172.16.12.13 |
| 8 | 172.16.12.14/31 | 172.16.12.14 – 172.16.12.15 | 172.16.12.15 |
| 9 | 172.16.12.16/31 | 172.16.12.16 – 172.16.12.17 | 172.16.12.17 |
| 10 | 172.16.12.18/31 | 172.16.12.18 – 172.16.12.19 | 172.16.12.19 |
| 11 | 172.16.12.20/31 | 172.16.12.20 – 172.16.12.21 | 172.16.12.21 |
| 12 | 172.16.12.22/31 | 172.16.12.22 – 172.16.12.23 | 172.16.12.23 |
| 13 | 172.16.12.24/31 | 172.16.12.24 – 172.16.12.25 | 172.16.12.25 |
| 14 | 172.16.12.26/31 | 172.16.12.26 – 172.16.12.27 | 172.16.12.27 |
| 15 | 172.16.12.28/31 | 172.16.12.28 – 172.16.12.29 | 172.16.12.29 |
| 16 | 172.16.12.30/31 | 172.16.12.30 – 172.16.12.31 | 172.16.12.31 |
| 17 | 172.16.12.32/31 | 172.16.12.32 – 172.16.12.33 | 172.16.12.33 |
| 18 | 172.16.12.34/31 | 172.16.12.34 – 172.16.12.35 | 172.16.12.35 |
| 19 | 172.16.12.36/31 | 172.16.12.36 – 172.16.12.37 | 172.16.12.37 |
| 20 | 172.16.12.38/31 | 172.16.12.38 – 172.16.12.39 | 172.16.12.39 |
| 21 | 172.16.12.40/31 | 172.16.12.40 – 172.16.12.41 | 172.16.12.41 |
| 22 | 172.16.12.42/31 | 172.16.12.42 – 172.16.12.43 | 172.16.12.43 |
| 23 | 172.16.12.44/31 | 172.16.12.44 – 172.16.12.45 | 172.16.12.45 |
| 24 | 172.16.12.46/31 | 172.16.12.46 – 172.16.12.47 | 172.16.12.47 |
| 25 | 172.16.12.48/31 | 172.16.12.48 – 172.16.12.49 | 172.16.12.49 |
| 26 | 172.16.12.50/31 | 172.16.12.50 – 172.16.12.51 | 172.16.12.51 |
| 27 | 172.16.12.52/31 | 172.16.12.52 – 172.16.12.53 | 172.16.12.53 |
| 28 | 172.16.12.54/31 | 172.16.12.54 – 172.16.12.55 | 172.16.12.55 |
| 29 | 172.16.12.56/31 | 172.16.12.56 – 172.16.12.57 | 172.16.12.57 |
| 30 | 172.16.12.58/31 | 172.16.12.58 – 172.16.12.59 | 172.16.12.59 |
| 31 | 172.16.12.60/31 | 172.16.12.60 – 172.16.12.61 | 172.16.12.61 |
| 32 | 172.16.12.62/31 | 172.16.12.62 – 172.16.12.63 | 172.16.12.63 |
| 33 | 172.16.12.64/31 | 172.16.12.64 – 172.16.12.65 | 172.16.12.65 |
| 34 | 172.16.12.66/31 | 172.16.12.66 – 172.16.12.67 | 172.16.12.67 |
| 35 | 172.16.12.68/31 | 172.16.12.68 – 172.16.12.69 | 172.16.12.69 |
| 36 | 172.16.12.70/31 | 172.16.12.70 – 172.16.12.71 | 172.16.12.71 |
| 37 | 172.16.12.72/31 | 172.16.12.72 – 172.16.12.73 | 172.16.12.73 |
| 38 | 172.16.12.74/31 | 172.16.12.74 – 172.16.12.75 | 172.16.12.75 |
| 39 | 172.16.12.76/31 | 172.16.12.76 – 172.16.12.77 | 172.16.12.77 |
| 40 | 172.16.12.78/31 | 172.16.12.78 – 172.16.12.79 | 172.16.12.79 |
| 41 | 172.16.12.80/31 | 172.16.12.80 – 172.16.12.81 | 172.16.12.81 |
| 42 | 172.16.12.82/31 | 172.16.12.82 – 172.16.12.83 | 172.16.12.83 |
| 43 | 172.16.12.84/31 | 172.16.12.84 – 172.16.12.85 | 172.16.12.85 |
| 44 | 172.16.12.86/31 | 172.16.12.86 – 172.16.12.87 | 172.16.12.87 |
| 45 | 172.16.12.88/31 | 172.16.12.88 – 172.16.12.89 | 172.16.12.89 |
| 46 | 172.16.12.90/31 | 172.16.12.90 – 172.16.12.91 | 172.16.12.91 |
| 47 | 172.16.12.92/31 | 172.16.12.92 – 172.16.12.93 | 172.16.12.93 |
| 48 | 172.16.12.94/31 | 172.16.12.94 – 172.16.12.95 | 172.16.12.95 |
| 49 | 172.16.12.96/31 | 172.16.12.96 – 172.16.12.97 | 172.16.12.97 |
| 50 | 172.16.12.98/31 | 172.16.12.98 – 172.16.12.99 | 172.16.12.99 |
| 51 | 172.16.12.100/31 | 172.16.12.100 – 172.16.12.101 | 172.16.12.101 |
| 52 | 172.16.12.102/31 | 172.16.12.102 – 172.16.12.103 | 172.16.12.103 |
| 53 | 172.16.12.104/31 | 172.16.12.104 – 172.16.12.105 | 172.16.12.105 |
| 54 | 172.16.12.106/31 | 172.16.12.106 – 172.16.12.107 | 172.16.12.107 |
| 55 | 172.16.12.108/31 | 172.16.12.108 – 172.16.12.109 | 172.16.12.109 |
| 56 | 172.16.12.110/31 | 172.16.12.110 – 172.16.12.111 | 172.16.12.111 |
| 57 | 172.16.12.112/31 | 172.16.12.112 – 172.16.12.113 | 172.16.12.113 |
| 58 | 172.16.12.114/31 | 172.16.12.114 – 172.16.12.115 | 172.16.12.115 |
| 59 | 172.16.12.116/31 | 172.16.12.116 – 172.16.12.117 | 172.16.12.117 |
| 60 | 172.16.12.118/31 | 172.16.12.118 – 172.16.12.119 | 172.16.12.119 |
| 61 | 172.16.12.120/31 | 172.16.12.120 – 172.16.12.121 | 172.16.12.121 |
| 62 | 172.16.12.122/31 | 172.16.12.122 – 172.16.12.123 | 172.16.12.123 |
| 63 | 172.16.12.124/31 | 172.16.12.124 – 172.16.12.125 | 172.16.12.125 |
| 64 | 172.16.12.126/31 | 172.16.12.126 – 172.16.12.127 | 172.16.12.127 |
| 65 | 172.16.12.128/31 | 172.16.12.128 – 172.16.12.129 | 172.16.12.129 |
| 66 | 172.16.12.130/31 | 172.16.12.130 – 172.16.12.131 | 172.16.12.131 |
| 67 | 172.16.12.132/31 | 172.16.12.132 – 172.16.12.133 | 172.16.12.133 |
| 68 | 172.16.12.134/31 | 172.16.12.134 – 172.16.12.135 | 172.16.12.135 |
| 69 | 172.16.12.136/31 | 172.16.12.136 – 172.16.12.137 | 172.16.12.137 |
| 70 | 172.16.12.138/31 | 172.16.12.138 – 172.16.12.139 | 172.16.12.139 |
| 71 | 172.16.12.140/31 | 172.16.12.140 – 172.16.12.141 | 172.16.12.141 |
| 72 | 172.16.12.142/31 | 172.16.12.142 – 172.16.12.143 | 172.16.12.143 |
| 73 | 172.16.12.144/31 | 172.16.12.144 – 172.16.12.145 | 172.16.12.145 |
| 74 | 172.16.12.146/31 | 172.16.12.146 – 172.16.12.147 | 172.16.12.147 |
| 75 | 172.16.12.148/31 | 172.16.12.148 – 172.16.12.149 | 172.16.12.149 |
| 76 | 172.16.12.150/31 | 172.16.12.150 – 172.16.12.151 | 172.16.12.151 |
| 77 | 172.16.12.152/31 | 172.16.12.152 – 172.16.12.153 | 172.16.12.153 |
| 78 | 172.16.12.154/31 | 172.16.12.154 – 172.16.12.155 | 172.16.12.155 |
| 79 | 172.16.12.156/31 | 172.16.12.156 – 172.16.12.157 | 172.16.12.157 |
| 80 | 172.16.12.158/31 | 172.16.12.158 – 172.16.12.159 | 172.16.12.159 |
| 81 | 172.16.12.160/31 | 172.16.12.160 – 172.16.12.161 | 172.16.12.161 |
| 82 | 172.16.12.162/31 | 172.16.12.162 – 172.16.12.163 | 172.16.12.163 |
| 83 | 172.16.12.164/31 | 172.16.12.164 – 172.16.12.165 | 172.16.12.165 |
| 84 | 172.16.12.166/31 | 172.16.12.166 – 172.16.12.167 | 172.16.12.167 |
| 85 | 172.16.12.168/31 | 172.16.12.168 – 172.16.12.169 | 172.16.12.169 |
| 86 | 172.16.12.170/31 | 172.16.12.170 – 172.16.12.171 | 172.16.12.171 |
| 87 | 172.16.12.172/31 | 172.16.12.172 – 172.16.12.173 | 172.16.12.173 |
| 88 | 172.16.12.174/31 | 172.16.12.174 – 172.16.12.175 | 172.16.12.175 |
| 89 | 172.16.12.176/31 | 172.16.12.176 – 172.16.12.177 | 172.16.12.177 |
| 90 | 172.16.12.178/31 | 172.16.12.178 – 172.16.12.179 | 172.16.12.179 |
| 91 | 172.16.12.180/31 | 172.16.12.180 – 172.16.12.181 | 172.16.12.181 |
| 92 | 172.16.12.182/31 | 172.16.12.182 – 172.16.12.183 | 172.16.12.183 |
| 93 | 172.16.12.184/31 | 172.16.12.184 – 172.16.12.185 | 172.16.12.185 |
| 94 | 172.16.12.186/31 | 172.16.12.186 – 172.16.12.187 | 172.16.12.187 |
| 95 | 172.16.12.188/31 | 172.16.12.188 – 172.16.12.189 | 172.16.12.189 |
| 96 | 172.16.12.190/31 | 172.16.12.190 – 172.16.12.191 | 172.16.12.191 |
| 97 | 172.16.12.192/31 | 172.16.12.192 – 172.16.12.193 | 172.16.12.193 |
| 98 | 172.16.12.194/31 | 172.16.12.194 – 172.16.12.195 | 172.16.12.195 |
| 99 | 172.16.12.196/31 | 172.16.12.196 – 172.16.12.197 | 172.16.12.197 |
| 100 | 172.16.12.198/31 | 172.16.12.198 – 172.16.12.199 | 172.16.12.199 |
| 101 | 172.16.12.200/31 | 172.16.12.200 – 172.16.12.201 | 172.16.12.201 |
| 102 | 172.16.12.202/31 | 172.16.12.202 – 172.16.12.203 | 172.16.12.203 |
| 103 | 172.16.12.204/31 | 172.16.12.204 – 172.16.12.205 | 172.16.12.205 |
| 104 | 172.16.12.206/31 | 172.16.12.206 – 172.16.12.207 | 172.16.12.207 |
| 105 | 172.16.12.208/31 | 172.16.12.208 – 172.16.12.209 | 172.16.12.209 |
| 106 | 172.16.12.210/31 | 172.16.12.210 – 172.16.12.211 | 172.16.12.211 |
| 107 | 172.16.12.212/31 | 172.16.12.212 – 172.16.12.213 | 172.16.12.213 |
| 108 | 172.16.12.214/31 | 172.16.12.214 – 172.16.12.215 | 172.16.12.215 |
| 109 | 172.16.12.216/31 | 172.16.12.216 – 172.16.12.217 | 172.16.12.217 |
| 110 | 172.16.12.218/31 | 172.16.12.218 – 172.16.12.219 | 172.16.12.219 |
| 111 | 172.16.12.220/31 | 172.16.12.220 – 172.16.12.221 | 172.16.12.221 |
| 112 | 172.16.12.222/31 | 172.16.12.222 – 172.16.12.223 | 172.16.12.223 |
| 113 | 172.16.12.224/31 | 172.16.12.224 – 172.16.12.225 | 172.16.12.225 |
| 114 | 172.16.12.226/31 | 172.16.12.226 – 172.16.12.227 | 172.16.12.227 |
| 115 | 172.16.12.228/31 | 172.16.12.228 – 172.16.12.229 | 172.16.12.229 |
| 116 | 172.16.12.230/31 | 172.16.12.230 – 172.16.12.231 | 172.16.12.231 |
| 117 | 172.16.12.232/31 | 172.16.12.232 – 172.16.12.233 | 172.16.12.233 |
| 118 | 172.16.12.234/31 | 172.16.12.234 – 172.16.12.235 | 172.16.12.235 |
| 119 | 172.16.12.236/31 | 172.16.12.236 – 172.16.12.237 | 172.16.12.237 |
| 120 | 172.16.12.238/31 | 172.16.12.238 – 172.16.12.239 | 172.16.12.239 |
| 121 | 172.16.12.240/31 | 172.16.12.240 – 172.16.12.241 | 172.16.12.241 |
| 122 | 172.16.12.242/31 | 172.16.12.242 – 172.16.12.243 | 172.16.12.243 |
| 123 | 172.16.12.244/31 | 172.16.12.244 – 172.16.12.245 | 172.16.12.245 |
| 124 | 172.16.12.246/31 | 172.16.12.246 – 172.16.12.247 | 172.16.12.247 |
| 125 | 172.16.12.248/31 | 172.16.12.248 – 172.16.12.249 | 172.16.12.249 |
| 126 | 172.16.12.250/31 | 172.16.12.250 – 172.16.12.251 | 172.16.12.251 |
| 127 | 172.16.12.252/31 | 172.16.12.252 – 172.16.12.253 | 172.16.12.253 |
| 128 | 172.16.12.254/31 | 172.16.12.254 – 172.16.12.255 | 172.16.12.255 |
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 /24 |
|---|---|---|---|---|
| /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 | 1 |
| /25 | 255.255.255.128 | 128 | 126 | 2 split → |
| /26 | 255.255.255.192 | 64 | 62 | 4 split → |
| /27 | 255.255.255.224 | 32 | 30 | 8 split → |
| /28 | 255.255.255.240 | 16 | 14 | 16 split → |
| /29 | 255.255.255.248 | 8 | 6 | 32 split → |
| /30 | 255.255.255.252 | 4 | 2 | 64 split → |
| /31 | 255.255.255.254 | 2 | 2 | 128 split → |
| /32 | 255.255.255.255 | 1 | 1 | 256 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.