Calcudoku is a mathematical puzzle involving single digits and the basic operators. Epigram's infinite puzzle format randomises a grid of your choice so you can endlessly play during your online lectures...

Rules

1. You can define a grid size between 3x3 and 9x9. Please be patient with the page when loading larger grids as it can take a few seconds!
2. Depending on your selected size, each row or column can only contain one of each number in its range, e.g. 1-3, 1-9.
3. Once loaded, the colours of the squares define a section of the grid. Each section has a number and a mathematical operator (add, subtract, multiply, divide). These define the value of the squares within, when the operator is applied.
4. A congratulatory message will appear when you have successfully filled in the grid! Or you can give up and click the solve button... But why would you do that?

How many Calcudokus have you solved today?