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)10.0.8.0/24
network10.0.8.0/24
broadcast10.0.8.255
first host10.0.8.1
last host10.0.8.254
subnet mask255.255.255.0
wildcard0.0.0.255
addresses256
usable hosts254
classA
ipcalc 10.0.8.0/24
address00001010.00000000.00001000.00000000
subnet mask11111111.11111111.11111111.00000000
network00001010.00000000.00001000.00000000
broadcast00001010.00000000.00001000.11111111
green = network part, grey = host part
hex0x0a000800
decimal167774208
reverse dns0.8.0.10.in-addr.arpa
ipv4-mapped::ffff:a00:800

/24 split into /32 · 256 subnets

close ×
#networkhost rangebroadcast
110.0.8.0/3210.0.8.0 – 10.0.8.010.0.8.0
210.0.8.1/3210.0.8.1 – 10.0.8.110.0.8.1
310.0.8.2/3210.0.8.2 – 10.0.8.210.0.8.2
410.0.8.3/3210.0.8.3 – 10.0.8.310.0.8.3
510.0.8.4/3210.0.8.4 – 10.0.8.410.0.8.4
610.0.8.5/3210.0.8.5 – 10.0.8.510.0.8.5
710.0.8.6/3210.0.8.6 – 10.0.8.610.0.8.6
810.0.8.7/3210.0.8.7 – 10.0.8.710.0.8.7
910.0.8.8/3210.0.8.8 – 10.0.8.810.0.8.8
1010.0.8.9/3210.0.8.9 – 10.0.8.910.0.8.9
1110.0.8.10/3210.0.8.10 – 10.0.8.1010.0.8.10
1210.0.8.11/3210.0.8.11 – 10.0.8.1110.0.8.11
1310.0.8.12/3210.0.8.12 – 10.0.8.1210.0.8.12
1410.0.8.13/3210.0.8.13 – 10.0.8.1310.0.8.13
1510.0.8.14/3210.0.8.14 – 10.0.8.1410.0.8.14
1610.0.8.15/3210.0.8.15 – 10.0.8.1510.0.8.15
1710.0.8.16/3210.0.8.16 – 10.0.8.1610.0.8.16
1810.0.8.17/3210.0.8.17 – 10.0.8.1710.0.8.17
1910.0.8.18/3210.0.8.18 – 10.0.8.1810.0.8.18
2010.0.8.19/3210.0.8.19 – 10.0.8.1910.0.8.19
2110.0.8.20/3210.0.8.20 – 10.0.8.2010.0.8.20
2210.0.8.21/3210.0.8.21 – 10.0.8.2110.0.8.21
2310.0.8.22/3210.0.8.22 – 10.0.8.2210.0.8.22
2410.0.8.23/3210.0.8.23 – 10.0.8.2310.0.8.23
2510.0.8.24/3210.0.8.24 – 10.0.8.2410.0.8.24
2610.0.8.25/3210.0.8.25 – 10.0.8.2510.0.8.25
2710.0.8.26/3210.0.8.26 – 10.0.8.2610.0.8.26
2810.0.8.27/3210.0.8.27 – 10.0.8.2710.0.8.27
2910.0.8.28/3210.0.8.28 – 10.0.8.2810.0.8.28
3010.0.8.29/3210.0.8.29 – 10.0.8.2910.0.8.29
3110.0.8.30/3210.0.8.30 – 10.0.8.3010.0.8.30
3210.0.8.31/3210.0.8.31 – 10.0.8.3110.0.8.31
3310.0.8.32/3210.0.8.32 – 10.0.8.3210.0.8.32
3410.0.8.33/3210.0.8.33 – 10.0.8.3310.0.8.33
3510.0.8.34/3210.0.8.34 – 10.0.8.3410.0.8.34
3610.0.8.35/3210.0.8.35 – 10.0.8.3510.0.8.35
3710.0.8.36/3210.0.8.36 – 10.0.8.3610.0.8.36
3810.0.8.37/3210.0.8.37 – 10.0.8.3710.0.8.37
3910.0.8.38/3210.0.8.38 – 10.0.8.3810.0.8.38
4010.0.8.39/3210.0.8.39 – 10.0.8.3910.0.8.39
4110.0.8.40/3210.0.8.40 – 10.0.8.4010.0.8.40
4210.0.8.41/3210.0.8.41 – 10.0.8.4110.0.8.41
4310.0.8.42/3210.0.8.42 – 10.0.8.4210.0.8.42
4410.0.8.43/3210.0.8.43 – 10.0.8.4310.0.8.43
4510.0.8.44/3210.0.8.44 – 10.0.8.4410.0.8.44
4610.0.8.45/3210.0.8.45 – 10.0.8.4510.0.8.45
4710.0.8.46/3210.0.8.46 – 10.0.8.4610.0.8.46
4810.0.8.47/3210.0.8.47 – 10.0.8.4710.0.8.47
4910.0.8.48/3210.0.8.48 – 10.0.8.4810.0.8.48
5010.0.8.49/3210.0.8.49 – 10.0.8.4910.0.8.49
5110.0.8.50/3210.0.8.50 – 10.0.8.5010.0.8.50
5210.0.8.51/3210.0.8.51 – 10.0.8.5110.0.8.51
5310.0.8.52/3210.0.8.52 – 10.0.8.5210.0.8.52
5410.0.8.53/3210.0.8.53 – 10.0.8.5310.0.8.53
5510.0.8.54/3210.0.8.54 – 10.0.8.5410.0.8.54
5610.0.8.55/3210.0.8.55 – 10.0.8.5510.0.8.55
5710.0.8.56/3210.0.8.56 – 10.0.8.5610.0.8.56
5810.0.8.57/3210.0.8.57 – 10.0.8.5710.0.8.57
5910.0.8.58/3210.0.8.58 – 10.0.8.5810.0.8.58
6010.0.8.59/3210.0.8.59 – 10.0.8.5910.0.8.59
6110.0.8.60/3210.0.8.60 – 10.0.8.6010.0.8.60
6210.0.8.61/3210.0.8.61 – 10.0.8.6110.0.8.61
6310.0.8.62/3210.0.8.62 – 10.0.8.6210.0.8.62
6410.0.8.63/3210.0.8.63 – 10.0.8.6310.0.8.63
6510.0.8.64/3210.0.8.64 – 10.0.8.6410.0.8.64
6610.0.8.65/3210.0.8.65 – 10.0.8.6510.0.8.65
6710.0.8.66/3210.0.8.66 – 10.0.8.6610.0.8.66
6810.0.8.67/3210.0.8.67 – 10.0.8.6710.0.8.67
6910.0.8.68/3210.0.8.68 – 10.0.8.6810.0.8.68
7010.0.8.69/3210.0.8.69 – 10.0.8.6910.0.8.69
7110.0.8.70/3210.0.8.70 – 10.0.8.7010.0.8.70
7210.0.8.71/3210.0.8.71 – 10.0.8.7110.0.8.71
7310.0.8.72/3210.0.8.72 – 10.0.8.7210.0.8.72
7410.0.8.73/3210.0.8.73 – 10.0.8.7310.0.8.73
7510.0.8.74/3210.0.8.74 – 10.0.8.7410.0.8.74
7610.0.8.75/3210.0.8.75 – 10.0.8.7510.0.8.75
7710.0.8.76/3210.0.8.76 – 10.0.8.7610.0.8.76
7810.0.8.77/3210.0.8.77 – 10.0.8.7710.0.8.77
7910.0.8.78/3210.0.8.78 – 10.0.8.7810.0.8.78
8010.0.8.79/3210.0.8.79 – 10.0.8.7910.0.8.79
8110.0.8.80/3210.0.8.80 – 10.0.8.8010.0.8.80
8210.0.8.81/3210.0.8.81 – 10.0.8.8110.0.8.81
8310.0.8.82/3210.0.8.82 – 10.0.8.8210.0.8.82
8410.0.8.83/3210.0.8.83 – 10.0.8.8310.0.8.83
8510.0.8.84/3210.0.8.84 – 10.0.8.8410.0.8.84
8610.0.8.85/3210.0.8.85 – 10.0.8.8510.0.8.85
8710.0.8.86/3210.0.8.86 – 10.0.8.8610.0.8.86
8810.0.8.87/3210.0.8.87 – 10.0.8.8710.0.8.87
8910.0.8.88/3210.0.8.88 – 10.0.8.8810.0.8.88
9010.0.8.89/3210.0.8.89 – 10.0.8.8910.0.8.89
9110.0.8.90/3210.0.8.90 – 10.0.8.9010.0.8.90
9210.0.8.91/3210.0.8.91 – 10.0.8.9110.0.8.91
9310.0.8.92/3210.0.8.92 – 10.0.8.9210.0.8.92
9410.0.8.93/3210.0.8.93 – 10.0.8.9310.0.8.93
9510.0.8.94/3210.0.8.94 – 10.0.8.9410.0.8.94
9610.0.8.95/3210.0.8.95 – 10.0.8.9510.0.8.95
9710.0.8.96/3210.0.8.96 – 10.0.8.9610.0.8.96
9810.0.8.97/3210.0.8.97 – 10.0.8.9710.0.8.97
9910.0.8.98/3210.0.8.98 – 10.0.8.9810.0.8.98
10010.0.8.99/3210.0.8.99 – 10.0.8.9910.0.8.99
10110.0.8.100/3210.0.8.100 – 10.0.8.10010.0.8.100
10210.0.8.101/3210.0.8.101 – 10.0.8.10110.0.8.101
10310.0.8.102/3210.0.8.102 – 10.0.8.10210.0.8.102
10410.0.8.103/3210.0.8.103 – 10.0.8.10310.0.8.103
10510.0.8.104/3210.0.8.104 – 10.0.8.10410.0.8.104
10610.0.8.105/3210.0.8.105 – 10.0.8.10510.0.8.105
10710.0.8.106/3210.0.8.106 – 10.0.8.10610.0.8.106
10810.0.8.107/3210.0.8.107 – 10.0.8.10710.0.8.107
10910.0.8.108/3210.0.8.108 – 10.0.8.10810.0.8.108
11010.0.8.109/3210.0.8.109 – 10.0.8.10910.0.8.109
11110.0.8.110/3210.0.8.110 – 10.0.8.11010.0.8.110
11210.0.8.111/3210.0.8.111 – 10.0.8.11110.0.8.111
11310.0.8.112/3210.0.8.112 – 10.0.8.11210.0.8.112
11410.0.8.113/3210.0.8.113 – 10.0.8.11310.0.8.113
11510.0.8.114/3210.0.8.114 – 10.0.8.11410.0.8.114
11610.0.8.115/3210.0.8.115 – 10.0.8.11510.0.8.115
11710.0.8.116/3210.0.8.116 – 10.0.8.11610.0.8.116
11810.0.8.117/3210.0.8.117 – 10.0.8.11710.0.8.117
11910.0.8.118/3210.0.8.118 – 10.0.8.11810.0.8.118
12010.0.8.119/3210.0.8.119 – 10.0.8.11910.0.8.119
12110.0.8.120/3210.0.8.120 – 10.0.8.12010.0.8.120
12210.0.8.121/3210.0.8.121 – 10.0.8.12110.0.8.121
12310.0.8.122/3210.0.8.122 – 10.0.8.12210.0.8.122
12410.0.8.123/3210.0.8.123 – 10.0.8.12310.0.8.123
12510.0.8.124/3210.0.8.124 – 10.0.8.12410.0.8.124
12610.0.8.125/3210.0.8.125 – 10.0.8.12510.0.8.125
12710.0.8.126/3210.0.8.126 – 10.0.8.12610.0.8.126
12810.0.8.127/3210.0.8.127 – 10.0.8.12710.0.8.127
12910.0.8.128/3210.0.8.128 – 10.0.8.12810.0.8.128
13010.0.8.129/3210.0.8.129 – 10.0.8.12910.0.8.129
13110.0.8.130/3210.0.8.130 – 10.0.8.13010.0.8.130
13210.0.8.131/3210.0.8.131 – 10.0.8.13110.0.8.131
13310.0.8.132/3210.0.8.132 – 10.0.8.13210.0.8.132
13410.0.8.133/3210.0.8.133 – 10.0.8.13310.0.8.133
13510.0.8.134/3210.0.8.134 – 10.0.8.13410.0.8.134
13610.0.8.135/3210.0.8.135 – 10.0.8.13510.0.8.135
13710.0.8.136/3210.0.8.136 – 10.0.8.13610.0.8.136
13810.0.8.137/3210.0.8.137 – 10.0.8.13710.0.8.137
13910.0.8.138/3210.0.8.138 – 10.0.8.13810.0.8.138
14010.0.8.139/3210.0.8.139 – 10.0.8.13910.0.8.139
14110.0.8.140/3210.0.8.140 – 10.0.8.14010.0.8.140
14210.0.8.141/3210.0.8.141 – 10.0.8.14110.0.8.141
14310.0.8.142/3210.0.8.142 – 10.0.8.14210.0.8.142
14410.0.8.143/3210.0.8.143 – 10.0.8.14310.0.8.143
14510.0.8.144/3210.0.8.144 – 10.0.8.14410.0.8.144
14610.0.8.145/3210.0.8.145 – 10.0.8.14510.0.8.145
14710.0.8.146/3210.0.8.146 – 10.0.8.14610.0.8.146
14810.0.8.147/3210.0.8.147 – 10.0.8.14710.0.8.147
14910.0.8.148/3210.0.8.148 – 10.0.8.14810.0.8.148
15010.0.8.149/3210.0.8.149 – 10.0.8.14910.0.8.149
15110.0.8.150/3210.0.8.150 – 10.0.8.15010.0.8.150
15210.0.8.151/3210.0.8.151 – 10.0.8.15110.0.8.151
15310.0.8.152/3210.0.8.152 – 10.0.8.15210.0.8.152
15410.0.8.153/3210.0.8.153 – 10.0.8.15310.0.8.153
15510.0.8.154/3210.0.8.154 – 10.0.8.15410.0.8.154
15610.0.8.155/3210.0.8.155 – 10.0.8.15510.0.8.155
15710.0.8.156/3210.0.8.156 – 10.0.8.15610.0.8.156
15810.0.8.157/3210.0.8.157 – 10.0.8.15710.0.8.157
15910.0.8.158/3210.0.8.158 – 10.0.8.15810.0.8.158
16010.0.8.159/3210.0.8.159 – 10.0.8.15910.0.8.159
16110.0.8.160/3210.0.8.160 – 10.0.8.16010.0.8.160
16210.0.8.161/3210.0.8.161 – 10.0.8.16110.0.8.161
16310.0.8.162/3210.0.8.162 – 10.0.8.16210.0.8.162
16410.0.8.163/3210.0.8.163 – 10.0.8.16310.0.8.163
16510.0.8.164/3210.0.8.164 – 10.0.8.16410.0.8.164
16610.0.8.165/3210.0.8.165 – 10.0.8.16510.0.8.165
16710.0.8.166/3210.0.8.166 – 10.0.8.16610.0.8.166
16810.0.8.167/3210.0.8.167 – 10.0.8.16710.0.8.167
16910.0.8.168/3210.0.8.168 – 10.0.8.16810.0.8.168
17010.0.8.169/3210.0.8.169 – 10.0.8.16910.0.8.169
17110.0.8.170/3210.0.8.170 – 10.0.8.17010.0.8.170
17210.0.8.171/3210.0.8.171 – 10.0.8.17110.0.8.171
17310.0.8.172/3210.0.8.172 – 10.0.8.17210.0.8.172
17410.0.8.173/3210.0.8.173 – 10.0.8.17310.0.8.173
17510.0.8.174/3210.0.8.174 – 10.0.8.17410.0.8.174
17610.0.8.175/3210.0.8.175 – 10.0.8.17510.0.8.175
17710.0.8.176/3210.0.8.176 – 10.0.8.17610.0.8.176
17810.0.8.177/3210.0.8.177 – 10.0.8.17710.0.8.177
17910.0.8.178/3210.0.8.178 – 10.0.8.17810.0.8.178
18010.0.8.179/3210.0.8.179 – 10.0.8.17910.0.8.179
18110.0.8.180/3210.0.8.180 – 10.0.8.18010.0.8.180
18210.0.8.181/3210.0.8.181 – 10.0.8.18110.0.8.181
18310.0.8.182/3210.0.8.182 – 10.0.8.18210.0.8.182
18410.0.8.183/3210.0.8.183 – 10.0.8.18310.0.8.183
18510.0.8.184/3210.0.8.184 – 10.0.8.18410.0.8.184
18610.0.8.185/3210.0.8.185 – 10.0.8.18510.0.8.185
18710.0.8.186/3210.0.8.186 – 10.0.8.18610.0.8.186
18810.0.8.187/3210.0.8.187 – 10.0.8.18710.0.8.187
18910.0.8.188/3210.0.8.188 – 10.0.8.18810.0.8.188
19010.0.8.189/3210.0.8.189 – 10.0.8.18910.0.8.189
19110.0.8.190/3210.0.8.190 – 10.0.8.19010.0.8.190
19210.0.8.191/3210.0.8.191 – 10.0.8.19110.0.8.191
19310.0.8.192/3210.0.8.192 – 10.0.8.19210.0.8.192
19410.0.8.193/3210.0.8.193 – 10.0.8.19310.0.8.193
19510.0.8.194/3210.0.8.194 – 10.0.8.19410.0.8.194
19610.0.8.195/3210.0.8.195 – 10.0.8.19510.0.8.195
19710.0.8.196/3210.0.8.196 – 10.0.8.19610.0.8.196
19810.0.8.197/3210.0.8.197 – 10.0.8.19710.0.8.197
19910.0.8.198/3210.0.8.198 – 10.0.8.19810.0.8.198
20010.0.8.199/3210.0.8.199 – 10.0.8.19910.0.8.199
20110.0.8.200/3210.0.8.200 – 10.0.8.20010.0.8.200
20210.0.8.201/3210.0.8.201 – 10.0.8.20110.0.8.201
20310.0.8.202/3210.0.8.202 – 10.0.8.20210.0.8.202
20410.0.8.203/3210.0.8.203 – 10.0.8.20310.0.8.203
20510.0.8.204/3210.0.8.204 – 10.0.8.20410.0.8.204
20610.0.8.205/3210.0.8.205 – 10.0.8.20510.0.8.205
20710.0.8.206/3210.0.8.206 – 10.0.8.20610.0.8.206
20810.0.8.207/3210.0.8.207 – 10.0.8.20710.0.8.207
20910.0.8.208/3210.0.8.208 – 10.0.8.20810.0.8.208
21010.0.8.209/3210.0.8.209 – 10.0.8.20910.0.8.209
21110.0.8.210/3210.0.8.210 – 10.0.8.21010.0.8.210
21210.0.8.211/3210.0.8.211 – 10.0.8.21110.0.8.211
21310.0.8.212/3210.0.8.212 – 10.0.8.21210.0.8.212
21410.0.8.213/3210.0.8.213 – 10.0.8.21310.0.8.213
21510.0.8.214/3210.0.8.214 – 10.0.8.21410.0.8.214
21610.0.8.215/3210.0.8.215 – 10.0.8.21510.0.8.215
21710.0.8.216/3210.0.8.216 – 10.0.8.21610.0.8.216
21810.0.8.217/3210.0.8.217 – 10.0.8.21710.0.8.217
21910.0.8.218/3210.0.8.218 – 10.0.8.21810.0.8.218
22010.0.8.219/3210.0.8.219 – 10.0.8.21910.0.8.219
22110.0.8.220/3210.0.8.220 – 10.0.8.22010.0.8.220
22210.0.8.221/3210.0.8.221 – 10.0.8.22110.0.8.221
22310.0.8.222/3210.0.8.222 – 10.0.8.22210.0.8.222
22410.0.8.223/3210.0.8.223 – 10.0.8.22310.0.8.223
22510.0.8.224/3210.0.8.224 – 10.0.8.22410.0.8.224
22610.0.8.225/3210.0.8.225 – 10.0.8.22510.0.8.225
22710.0.8.226/3210.0.8.226 – 10.0.8.22610.0.8.226
22810.0.8.227/3210.0.8.227 – 10.0.8.22710.0.8.227
22910.0.8.228/3210.0.8.228 – 10.0.8.22810.0.8.228
23010.0.8.229/3210.0.8.229 – 10.0.8.22910.0.8.229
23110.0.8.230/3210.0.8.230 – 10.0.8.23010.0.8.230
23210.0.8.231/3210.0.8.231 – 10.0.8.23110.0.8.231
23310.0.8.232/3210.0.8.232 – 10.0.8.23210.0.8.232
23410.0.8.233/3210.0.8.233 – 10.0.8.23310.0.8.233
23510.0.8.234/3210.0.8.234 – 10.0.8.23410.0.8.234
23610.0.8.235/3210.0.8.235 – 10.0.8.23510.0.8.235
23710.0.8.236/3210.0.8.236 – 10.0.8.23610.0.8.236
23810.0.8.237/3210.0.8.237 – 10.0.8.23710.0.8.237
23910.0.8.238/3210.0.8.238 – 10.0.8.23810.0.8.238
24010.0.8.239/3210.0.8.239 – 10.0.8.23910.0.8.239
24110.0.8.240/3210.0.8.240 – 10.0.8.24010.0.8.240
24210.0.8.241/3210.0.8.241 – 10.0.8.24110.0.8.241
24310.0.8.242/3210.0.8.242 – 10.0.8.24210.0.8.242
24410.0.8.243/3210.0.8.243 – 10.0.8.24310.0.8.243
24510.0.8.244/3210.0.8.244 – 10.0.8.24410.0.8.244
24610.0.8.245/3210.0.8.245 – 10.0.8.24510.0.8.245
24710.0.8.246/3210.0.8.246 – 10.0.8.24610.0.8.246
24810.0.8.247/3210.0.8.247 – 10.0.8.24710.0.8.247
24910.0.8.248/3210.0.8.248 – 10.0.8.24810.0.8.248
25010.0.8.249/3210.0.8.249 – 10.0.8.24910.0.8.249
25110.0.8.250/3210.0.8.250 – 10.0.8.25010.0.8.250
25210.0.8.251/3210.0.8.251 – 10.0.8.25110.0.8.251
25310.0.8.252/3210.0.8.252 – 10.0.8.25210.0.8.252
25410.0.8.253/3210.0.8.253 – 10.0.8.25310.0.8.253
25510.0.8.254/3210.0.8.254 – 10.0.8.25410.0.8.254
25610.0.8.255/3210.0.8.255 – 10.0.8.25510.0.8.255
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 →