The rules for CalcDoku (or otherwise also known as MathDoku) are similar to sudoku. Every number may appear only once in each row and in each columns. BUt no number is given at the beginning instead there are the results of calculations of the numbers that are in the fields of the same block. It is also given which operator (+, - , *, or / ) has to be used to reach the result.

CalcDoku/MathDoku game can be played also in the Nintendo 3DS browser