ip
ipku.in

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.

$ ipcalc
private IP (RFC 1918)10.112.3.0/24
network10.112.3.0/24
broadcast10.112.3.255
first host10.112.3.1
last host10.112.3.254
subnet mask255.255.255.0
wildcard0.0.0.255
addresses256
usable hosts254
classA
ipcalc 10.112.3.0/24
address00001010.01110000.00000011.00000000
subnet mask11111111.11111111.11111111.00000000
network00001010.01110000.00000011.00000000
broadcast00001010.01110000.00000011.11111111
green = network part, grey = host part
hex0x0a700300
decimal175112960
reverse dns0.3.112.10.in-addr.arpa
ipv4-mapped::ffff:a70:300

/24 split into /32 · 256 subnets

close ×
#networkhost rangebroadcast
110.112.3.0/3210.112.3.0 – 10.112.3.010.112.3.0
210.112.3.1/3210.112.3.1 – 10.112.3.110.112.3.1
310.112.3.2/3210.112.3.2 – 10.112.3.210.112.3.2
410.112.3.3/3210.112.3.3 – 10.112.3.310.112.3.3
510.112.3.4/3210.112.3.4 – 10.112.3.410.112.3.4
610.112.3.5/3210.112.3.5 – 10.112.3.510.112.3.5
710.112.3.6/3210.112.3.6 – 10.112.3.610.112.3.6
810.112.3.7/3210.112.3.7 – 10.112.3.710.112.3.7
910.112.3.8/3210.112.3.8 – 10.112.3.810.112.3.8
1010.112.3.9/3210.112.3.9 – 10.112.3.910.112.3.9
1110.112.3.10/3210.112.3.10 – 10.112.3.1010.112.3.10
1210.112.3.11/3210.112.3.11 – 10.112.3.1110.112.3.11
1310.112.3.12/3210.112.3.12 – 10.112.3.1210.112.3.12
1410.112.3.13/3210.112.3.13 – 10.112.3.1310.112.3.13
1510.112.3.14/3210.112.3.14 – 10.112.3.1410.112.3.14
1610.112.3.15/3210.112.3.15 – 10.112.3.1510.112.3.15
1710.112.3.16/3210.112.3.16 – 10.112.3.1610.112.3.16
1810.112.3.17/3210.112.3.17 – 10.112.3.1710.112.3.17
1910.112.3.18/3210.112.3.18 – 10.112.3.1810.112.3.18
2010.112.3.19/3210.112.3.19 – 10.112.3.1910.112.3.19
2110.112.3.20/3210.112.3.20 – 10.112.3.2010.112.3.20
2210.112.3.21/3210.112.3.21 – 10.112.3.2110.112.3.21
2310.112.3.22/3210.112.3.22 – 10.112.3.2210.112.3.22
2410.112.3.23/3210.112.3.23 – 10.112.3.2310.112.3.23
2510.112.3.24/3210.112.3.24 – 10.112.3.2410.112.3.24
2610.112.3.25/3210.112.3.25 – 10.112.3.2510.112.3.25
2710.112.3.26/3210.112.3.26 – 10.112.3.2610.112.3.26
2810.112.3.27/3210.112.3.27 – 10.112.3.2710.112.3.27
2910.112.3.28/3210.112.3.28 – 10.112.3.2810.112.3.28
3010.112.3.29/3210.112.3.29 – 10.112.3.2910.112.3.29
3110.112.3.30/3210.112.3.30 – 10.112.3.3010.112.3.30
3210.112.3.31/3210.112.3.31 – 10.112.3.3110.112.3.31
3310.112.3.32/3210.112.3.32 – 10.112.3.3210.112.3.32
3410.112.3.33/3210.112.3.33 – 10.112.3.3310.112.3.33
3510.112.3.34/3210.112.3.34 – 10.112.3.3410.112.3.34
3610.112.3.35/3210.112.3.35 – 10.112.3.3510.112.3.35
3710.112.3.36/3210.112.3.36 – 10.112.3.3610.112.3.36
3810.112.3.37/3210.112.3.37 – 10.112.3.3710.112.3.37
3910.112.3.38/3210.112.3.38 – 10.112.3.3810.112.3.38
4010.112.3.39/3210.112.3.39 – 10.112.3.3910.112.3.39
4110.112.3.40/3210.112.3.40 – 10.112.3.4010.112.3.40
4210.112.3.41/3210.112.3.41 – 10.112.3.4110.112.3.41
4310.112.3.42/3210.112.3.42 – 10.112.3.4210.112.3.42
4410.112.3.43/3210.112.3.43 – 10.112.3.4310.112.3.43
4510.112.3.44/3210.112.3.44 – 10.112.3.4410.112.3.44
4610.112.3.45/3210.112.3.45 – 10.112.3.4510.112.3.45
4710.112.3.46/3210.112.3.46 – 10.112.3.4610.112.3.46
4810.112.3.47/3210.112.3.47 – 10.112.3.4710.112.3.47
4910.112.3.48/3210.112.3.48 – 10.112.3.4810.112.3.48
5010.112.3.49/3210.112.3.49 – 10.112.3.4910.112.3.49
5110.112.3.50/3210.112.3.50 – 10.112.3.5010.112.3.50
5210.112.3.51/3210.112.3.51 – 10.112.3.5110.112.3.51
5310.112.3.52/3210.112.3.52 – 10.112.3.5210.112.3.52
5410.112.3.53/3210.112.3.53 – 10.112.3.5310.112.3.53
5510.112.3.54/3210.112.3.54 – 10.112.3.5410.112.3.54
5610.112.3.55/3210.112.3.55 – 10.112.3.5510.112.3.55
5710.112.3.56/3210.112.3.56 – 10.112.3.5610.112.3.56
5810.112.3.57/3210.112.3.57 – 10.112.3.5710.112.3.57
5910.112.3.58/3210.112.3.58 – 10.112.3.5810.112.3.58
6010.112.3.59/3210.112.3.59 – 10.112.3.5910.112.3.59
6110.112.3.60/3210.112.3.60 – 10.112.3.6010.112.3.60
6210.112.3.61/3210.112.3.61 – 10.112.3.6110.112.3.61
6310.112.3.62/3210.112.3.62 – 10.112.3.6210.112.3.62
6410.112.3.63/3210.112.3.63 – 10.112.3.6310.112.3.63
6510.112.3.64/3210.112.3.64 – 10.112.3.6410.112.3.64
6610.112.3.65/3210.112.3.65 – 10.112.3.6510.112.3.65
6710.112.3.66/3210.112.3.66 – 10.112.3.6610.112.3.66
6810.112.3.67/3210.112.3.67 – 10.112.3.6710.112.3.67
6910.112.3.68/3210.112.3.68 – 10.112.3.6810.112.3.68
7010.112.3.69/3210.112.3.69 – 10.112.3.6910.112.3.69
7110.112.3.70/3210.112.3.70 – 10.112.3.7010.112.3.70
7210.112.3.71/3210.112.3.71 – 10.112.3.7110.112.3.71
7310.112.3.72/3210.112.3.72 – 10.112.3.7210.112.3.72
7410.112.3.73/3210.112.3.73 – 10.112.3.7310.112.3.73
7510.112.3.74/3210.112.3.74 – 10.112.3.7410.112.3.74
7610.112.3.75/3210.112.3.75 – 10.112.3.7510.112.3.75
7710.112.3.76/3210.112.3.76 – 10.112.3.7610.112.3.76
7810.112.3.77/3210.112.3.77 – 10.112.3.7710.112.3.77
7910.112.3.78/3210.112.3.78 – 10.112.3.7810.112.3.78
8010.112.3.79/3210.112.3.79 – 10.112.3.7910.112.3.79
8110.112.3.80/3210.112.3.80 – 10.112.3.8010.112.3.80
8210.112.3.81/3210.112.3.81 – 10.112.3.8110.112.3.81
8310.112.3.82/3210.112.3.82 – 10.112.3.8210.112.3.82
8410.112.3.83/3210.112.3.83 – 10.112.3.8310.112.3.83
8510.112.3.84/3210.112.3.84 – 10.112.3.8410.112.3.84
8610.112.3.85/3210.112.3.85 – 10.112.3.8510.112.3.85
8710.112.3.86/3210.112.3.86 – 10.112.3.8610.112.3.86
8810.112.3.87/3210.112.3.87 – 10.112.3.8710.112.3.87
8910.112.3.88/3210.112.3.88 – 10.112.3.8810.112.3.88
9010.112.3.89/3210.112.3.89 – 10.112.3.8910.112.3.89
9110.112.3.90/3210.112.3.90 – 10.112.3.9010.112.3.90
9210.112.3.91/3210.112.3.91 – 10.112.3.9110.112.3.91
9310.112.3.92/3210.112.3.92 – 10.112.3.9210.112.3.92
9410.112.3.93/3210.112.3.93 – 10.112.3.9310.112.3.93
9510.112.3.94/3210.112.3.94 – 10.112.3.9410.112.3.94
9610.112.3.95/3210.112.3.95 – 10.112.3.9510.112.3.95
9710.112.3.96/3210.112.3.96 – 10.112.3.9610.112.3.96
9810.112.3.97/3210.112.3.97 – 10.112.3.9710.112.3.97
9910.112.3.98/3210.112.3.98 – 10.112.3.9810.112.3.98
10010.112.3.99/3210.112.3.99 – 10.112.3.9910.112.3.99
10110.112.3.100/3210.112.3.100 – 10.112.3.10010.112.3.100
10210.112.3.101/3210.112.3.101 – 10.112.3.10110.112.3.101
10310.112.3.102/3210.112.3.102 – 10.112.3.10210.112.3.102
10410.112.3.103/3210.112.3.103 – 10.112.3.10310.112.3.103
10510.112.3.104/3210.112.3.104 – 10.112.3.10410.112.3.104
10610.112.3.105/3210.112.3.105 – 10.112.3.10510.112.3.105
10710.112.3.106/3210.112.3.106 – 10.112.3.10610.112.3.106
10810.112.3.107/3210.112.3.107 – 10.112.3.10710.112.3.107
10910.112.3.108/3210.112.3.108 – 10.112.3.10810.112.3.108
11010.112.3.109/3210.112.3.109 – 10.112.3.10910.112.3.109
11110.112.3.110/3210.112.3.110 – 10.112.3.11010.112.3.110
11210.112.3.111/3210.112.3.111 – 10.112.3.11110.112.3.111
11310.112.3.112/3210.112.3.112 – 10.112.3.11210.112.3.112
11410.112.3.113/3210.112.3.113 – 10.112.3.11310.112.3.113
11510.112.3.114/3210.112.3.114 – 10.112.3.11410.112.3.114
11610.112.3.115/3210.112.3.115 – 10.112.3.11510.112.3.115
11710.112.3.116/3210.112.3.116 – 10.112.3.11610.112.3.116
11810.112.3.117/3210.112.3.117 – 10.112.3.11710.112.3.117
11910.112.3.118/3210.112.3.118 – 10.112.3.11810.112.3.118
12010.112.3.119/3210.112.3.119 – 10.112.3.11910.112.3.119
12110.112.3.120/3210.112.3.120 – 10.112.3.12010.112.3.120
12210.112.3.121/3210.112.3.121 – 10.112.3.12110.112.3.121
12310.112.3.122/3210.112.3.122 – 10.112.3.12210.112.3.122
12410.112.3.123/3210.112.3.123 – 10.112.3.12310.112.3.123
12510.112.3.124/3210.112.3.124 – 10.112.3.12410.112.3.124
12610.112.3.125/3210.112.3.125 – 10.112.3.12510.112.3.125
12710.112.3.126/3210.112.3.126 – 10.112.3.12610.112.3.126
12810.112.3.127/3210.112.3.127 – 10.112.3.12710.112.3.127
12910.112.3.128/3210.112.3.128 – 10.112.3.12810.112.3.128
13010.112.3.129/3210.112.3.129 – 10.112.3.12910.112.3.129
13110.112.3.130/3210.112.3.130 – 10.112.3.13010.112.3.130
13210.112.3.131/3210.112.3.131 – 10.112.3.13110.112.3.131
13310.112.3.132/3210.112.3.132 – 10.112.3.13210.112.3.132
13410.112.3.133/3210.112.3.133 – 10.112.3.13310.112.3.133
13510.112.3.134/3210.112.3.134 – 10.112.3.13410.112.3.134
13610.112.3.135/3210.112.3.135 – 10.112.3.13510.112.3.135
13710.112.3.136/3210.112.3.136 – 10.112.3.13610.112.3.136
13810.112.3.137/3210.112.3.137 – 10.112.3.13710.112.3.137
13910.112.3.138/3210.112.3.138 – 10.112.3.13810.112.3.138
14010.112.3.139/3210.112.3.139 – 10.112.3.13910.112.3.139
14110.112.3.140/3210.112.3.140 – 10.112.3.14010.112.3.140
14210.112.3.141/3210.112.3.141 – 10.112.3.14110.112.3.141
14310.112.3.142/3210.112.3.142 – 10.112.3.14210.112.3.142
14410.112.3.143/3210.112.3.143 – 10.112.3.14310.112.3.143
14510.112.3.144/3210.112.3.144 – 10.112.3.14410.112.3.144
14610.112.3.145/3210.112.3.145 – 10.112.3.14510.112.3.145
14710.112.3.146/3210.112.3.146 – 10.112.3.14610.112.3.146
14810.112.3.147/3210.112.3.147 – 10.112.3.14710.112.3.147
14910.112.3.148/3210.112.3.148 – 10.112.3.14810.112.3.148
15010.112.3.149/3210.112.3.149 – 10.112.3.14910.112.3.149
15110.112.3.150/3210.112.3.150 – 10.112.3.15010.112.3.150
15210.112.3.151/3210.112.3.151 – 10.112.3.15110.112.3.151
15310.112.3.152/3210.112.3.152 – 10.112.3.15210.112.3.152
15410.112.3.153/3210.112.3.153 – 10.112.3.15310.112.3.153
15510.112.3.154/3210.112.3.154 – 10.112.3.15410.112.3.154
15610.112.3.155/3210.112.3.155 – 10.112.3.15510.112.3.155
15710.112.3.156/3210.112.3.156 – 10.112.3.15610.112.3.156
15810.112.3.157/3210.112.3.157 – 10.112.3.15710.112.3.157
15910.112.3.158/3210.112.3.158 – 10.112.3.15810.112.3.158
16010.112.3.159/3210.112.3.159 – 10.112.3.15910.112.3.159
16110.112.3.160/3210.112.3.160 – 10.112.3.16010.112.3.160
16210.112.3.161/3210.112.3.161 – 10.112.3.16110.112.3.161
16310.112.3.162/3210.112.3.162 – 10.112.3.16210.112.3.162
16410.112.3.163/3210.112.3.163 – 10.112.3.16310.112.3.163
16510.112.3.164/3210.112.3.164 – 10.112.3.16410.112.3.164
16610.112.3.165/3210.112.3.165 – 10.112.3.16510.112.3.165
16710.112.3.166/3210.112.3.166 – 10.112.3.16610.112.3.166
16810.112.3.167/3210.112.3.167 – 10.112.3.16710.112.3.167
16910.112.3.168/3210.112.3.168 – 10.112.3.16810.112.3.168
17010.112.3.169/3210.112.3.169 – 10.112.3.16910.112.3.169
17110.112.3.170/3210.112.3.170 – 10.112.3.17010.112.3.170
17210.112.3.171/3210.112.3.171 – 10.112.3.17110.112.3.171
17310.112.3.172/3210.112.3.172 – 10.112.3.17210.112.3.172
17410.112.3.173/3210.112.3.173 – 10.112.3.17310.112.3.173
17510.112.3.174/3210.112.3.174 – 10.112.3.17410.112.3.174
17610.112.3.175/3210.112.3.175 – 10.112.3.17510.112.3.175
17710.112.3.176/3210.112.3.176 – 10.112.3.17610.112.3.176
17810.112.3.177/3210.112.3.177 – 10.112.3.17710.112.3.177
17910.112.3.178/3210.112.3.178 – 10.112.3.17810.112.3.178
18010.112.3.179/3210.112.3.179 – 10.112.3.17910.112.3.179
18110.112.3.180/3210.112.3.180 – 10.112.3.18010.112.3.180
18210.112.3.181/3210.112.3.181 – 10.112.3.18110.112.3.181
18310.112.3.182/3210.112.3.182 – 10.112.3.18210.112.3.182
18410.112.3.183/3210.112.3.183 – 10.112.3.18310.112.3.183
18510.112.3.184/3210.112.3.184 – 10.112.3.18410.112.3.184
18610.112.3.185/3210.112.3.185 – 10.112.3.18510.112.3.185
18710.112.3.186/3210.112.3.186 – 10.112.3.18610.112.3.186
18810.112.3.187/3210.112.3.187 – 10.112.3.18710.112.3.187
18910.112.3.188/3210.112.3.188 – 10.112.3.18810.112.3.188
19010.112.3.189/3210.112.3.189 – 10.112.3.18910.112.3.189
19110.112.3.190/3210.112.3.190 – 10.112.3.19010.112.3.190
19210.112.3.191/3210.112.3.191 – 10.112.3.19110.112.3.191
19310.112.3.192/3210.112.3.192 – 10.112.3.19210.112.3.192
19410.112.3.193/3210.112.3.193 – 10.112.3.19310.112.3.193
19510.112.3.194/3210.112.3.194 – 10.112.3.19410.112.3.194
19610.112.3.195/3210.112.3.195 – 10.112.3.19510.112.3.195
19710.112.3.196/3210.112.3.196 – 10.112.3.19610.112.3.196
19810.112.3.197/3210.112.3.197 – 10.112.3.19710.112.3.197
19910.112.3.198/3210.112.3.198 – 10.112.3.19810.112.3.198
20010.112.3.199/3210.112.3.199 – 10.112.3.19910.112.3.199
20110.112.3.200/3210.112.3.200 – 10.112.3.20010.112.3.200
20210.112.3.201/3210.112.3.201 – 10.112.3.20110.112.3.201
20310.112.3.202/3210.112.3.202 – 10.112.3.20210.112.3.202
20410.112.3.203/3210.112.3.203 – 10.112.3.20310.112.3.203
20510.112.3.204/3210.112.3.204 – 10.112.3.20410.112.3.204
20610.112.3.205/3210.112.3.205 – 10.112.3.20510.112.3.205
20710.112.3.206/3210.112.3.206 – 10.112.3.20610.112.3.206
20810.112.3.207/3210.112.3.207 – 10.112.3.20710.112.3.207
20910.112.3.208/3210.112.3.208 – 10.112.3.20810.112.3.208
21010.112.3.209/3210.112.3.209 – 10.112.3.20910.112.3.209
21110.112.3.210/3210.112.3.210 – 10.112.3.21010.112.3.210
21210.112.3.211/3210.112.3.211 – 10.112.3.21110.112.3.211
21310.112.3.212/3210.112.3.212 – 10.112.3.21210.112.3.212
21410.112.3.213/3210.112.3.213 – 10.112.3.21310.112.3.213
21510.112.3.214/3210.112.3.214 – 10.112.3.21410.112.3.214
21610.112.3.215/3210.112.3.215 – 10.112.3.21510.112.3.215
21710.112.3.216/3210.112.3.216 – 10.112.3.21610.112.3.216
21810.112.3.217/3210.112.3.217 – 10.112.3.21710.112.3.217
21910.112.3.218/3210.112.3.218 – 10.112.3.21810.112.3.218
22010.112.3.219/3210.112.3.219 – 10.112.3.21910.112.3.219
22110.112.3.220/3210.112.3.220 – 10.112.3.22010.112.3.220
22210.112.3.221/3210.112.3.221 – 10.112.3.22110.112.3.221
22310.112.3.222/3210.112.3.222 – 10.112.3.22210.112.3.222
22410.112.3.223/3210.112.3.223 – 10.112.3.22310.112.3.223
22510.112.3.224/3210.112.3.224 – 10.112.3.22410.112.3.224
22610.112.3.225/3210.112.3.225 – 10.112.3.22510.112.3.225
22710.112.3.226/3210.112.3.226 – 10.112.3.22610.112.3.226
22810.112.3.227/3210.112.3.227 – 10.112.3.22710.112.3.227
22910.112.3.228/3210.112.3.228 – 10.112.3.22810.112.3.228
23010.112.3.229/3210.112.3.229 – 10.112.3.22910.112.3.229
23110.112.3.230/3210.112.3.230 – 10.112.3.23010.112.3.230
23210.112.3.231/3210.112.3.231 – 10.112.3.23110.112.3.231
23310.112.3.232/3210.112.3.232 – 10.112.3.23210.112.3.232
23410.112.3.233/3210.112.3.233 – 10.112.3.23310.112.3.233
23510.112.3.234/3210.112.3.234 – 10.112.3.23410.112.3.234
23610.112.3.235/3210.112.3.235 – 10.112.3.23510.112.3.235
23710.112.3.236/3210.112.3.236 – 10.112.3.23610.112.3.236
23810.112.3.237/3210.112.3.237 – 10.112.3.23710.112.3.237
23910.112.3.238/3210.112.3.238 – 10.112.3.23810.112.3.238
24010.112.3.239/3210.112.3.239 – 10.112.3.23910.112.3.239
24110.112.3.240/3210.112.3.240 – 10.112.3.24010.112.3.240
24210.112.3.241/3210.112.3.241 – 10.112.3.24110.112.3.241
24310.112.3.242/3210.112.3.242 – 10.112.3.24210.112.3.242
24410.112.3.243/3210.112.3.243 – 10.112.3.24310.112.3.243
24510.112.3.244/3210.112.3.244 – 10.112.3.24410.112.3.244
24610.112.3.245/3210.112.3.245 – 10.112.3.24510.112.3.245
24710.112.3.246/3210.112.3.246 – 10.112.3.24610.112.3.246
24810.112.3.247/3210.112.3.247 – 10.112.3.24710.112.3.247
24910.112.3.248/3210.112.3.248 – 10.112.3.24810.112.3.248
25010.112.3.249/3210.112.3.249 – 10.112.3.24910.112.3.249
25110.112.3.250/3210.112.3.250 – 10.112.3.25010.112.3.250
25210.112.3.251/3210.112.3.251 – 10.112.3.25110.112.3.251
25310.112.3.252/3210.112.3.252 – 10.112.3.25210.112.3.252
25410.112.3.253/3210.112.3.253 – 10.112.3.25310.112.3.253
25510.112.3.254/3210.112.3.254 – 10.112.3.25410.112.3.254
25610.112.3.255/3210.112.3.255 – 10.112.3.25510.112.3.255
01 / table

IPv4 CIDR prefix table.

Click a prefix longer than your network to split it into subnets.

prefixsubnet maskaddresseshostsin your /24
/00.0.0.04,294,967,2964,294,967,294-
/1128.0.0.02,147,483,6482,147,483,646-
/2192.0.0.01,073,741,8241,073,741,822-
/3224.0.0.0536,870,912536,870,910-
/4240.0.0.0268,435,456268,435,454-
/5248.0.0.0134,217,728134,217,726-
/6252.0.0.067,108,86467,108,862-
/7254.0.0.033,554,43233,554,430-
/8255.0.0.016,777,21616,777,214-
/9255.128.0.08,388,6088,388,606-
/10255.192.0.04,194,3044,194,302-
/11255.224.0.02,097,1522,097,150-
/12255.240.0.01,048,5761,048,574-
/13255.248.0.0524,288524,286-
/14255.252.0.0262,144262,142-
/15255.254.0.0131,072131,070-
/16255.255.0.065,53665,534-
/17255.255.128.032,76832,766-
/18255.255.192.016,38416,382-
/19255.255.224.08,1928,190-
/20255.255.240.04,0964,094-
/21255.255.248.02,0482,046-
/22255.255.252.01,0241,022-
/23255.255.254.0512510-
/24255.255.255.02562541
/25255.255.255.1281281262 split →
/26255.255.255.19264624 split →
/27255.255.255.22432308 split →
/28255.255.255.240161416 split →
/29255.255.255.2488632 split →
/30255.255.255.2524264 split →
/31255.255.255.25422128 split →
/32255.255.255.25511256 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.

Learn how to work it out →