Calcudoku, free to play

Sudoku with arithmetic. Fill the grid so no digit repeats, and every outlined cage reaches its target.

How to play

Fill rows and columns
Use the digits 1 to the size of the grid once each in every row and every column.
Meet the cage targets
The small label in a cage gives its target and operation: 12× means multiply to 12, 3− means the two digits differ by 3.
Start with single squares
A cage with one square and just a number tells you that digit straight away. Then work outwards.

Quick answers about playing Calcudoku on Wittlo.

Is Calcudoku free?

Yes. It is free to play, with no sign-up and nothing to install.

What is Calcudoku?

A grid puzzle that joins the rules of Sudoku with simple arithmetic. It is also known as a cage-sum puzzle.

Does every puzzle have one answer?

Yes. A solver checks that each puzzle has exactly one solution.

How do subtract and divide cages work?

They always have two squares. For subtract, take the smaller digit from the larger. For divide, divide the larger by the smaller.

Can a digit repeat inside a cage?

Yes, if the squares are not in the same row or column.

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