Printable calcudoku
Calcudoku grids in PDF, from 4 × 4 for beginners to 6 × 6 for regulars. Calcudoku blends sudoku logic with mental arithmetic: every row and every column holds each digit once, and cages show a result and an operation to work out. Every grid has a single solution; the solutions are on the last pages.
How it works
Pick the size and the difficulty
A 4 × 4 grid is played with the digits 1 to 4, a 6 × 6 with the digits 1 to 6. Easy sticks to additions and subtractions, medium adds multiplications, hard uses all four operations in larger cages.
Set up the booklet
Choose the number of grids, A4 or Letter paper, and whether solutions are added. Cells are at least 14 mm wide: room for the result in the corner and your digit below it. The preview shows the first grid; “Another set” builds new ones.
Print and play
Start with the one-cell cages: their digit is given. Then look for cages with a single possibility, such as a two-cell 3+ (1 and 2) or a two-cell 6× (2 and 3). Each digit you place rules out others in its row and column.
Printing tips
Choose “Actual size” or “100%” in the print dialog, not “Fit to page”, to keep cells big enough to write in. Black and white is enough: there is no colour and no fill, only thin lines for the cells and thick ones for the cages. Use a pencil and an eraser, and jot the possible digits small in a corner of the cell. In class, calcudoku is mental arithmetic practice in disguise: easy 4 × 4 grids drill small additions and subtractions from age 7, medium grids bring back the times tables, hard ones add division. A booklet of 12 or 24 grids fills an independent work station or a quiet moment; each pupil goes at their own pace, and all the grids are different. Print the solution pages on a separate sheet, for self-checking or to keep at the desk.
Frequently asked questions
What are the rules of calcudoku?
In a grid 4 cells wide, write the digits 1 to 4 (1 to 5 or 1 to 6 for larger grids): each appears only once in every row and every column. The grid is cut into cages with a thick outline. Each cage shows a result and an operation: the digits of the cage, added, subtracted, multiplied or divided, must give that result. A one-cell cage simply gives its digit.
In which order do I subtract or divide?
In the order that works out. Subtraction and division cages always have two cells, and you start from the larger digit: a 2÷ cage can hold 2 and 1, 4 and 2 or 6 and 3, either way round. A 1− cage holds two consecutive digits.
Can a digit repeat inside a cage?
Yes, if the two cells are neither in the same row nor in the same column. In an L-shaped cage, for instance, both ends can carry the same digit.
How is it different from sudoku?
Sudoku gives digits at the start and needs no arithmetic. Calcudoku gives few digits, sometimes none: the operations are the clues. There are no boxes, only rows, columns and cages.
Does each grid have a single solution?
Yes. Every grid is checked before layout: exactly one solution exists, and it is found by deduction, with no guessing.
From what age?
Around 7 for easy 4 × 4 grids, once small additions and subtractions are secure. Grids with multiplications suit ages 8 or 9 and up, hard 6 × 6 grids suit teenagers and adults.
Can I use them in class or in a club?
Yes, freely, including printing them in quantity. Only reselling the files is not allowed.
Are my settings saved?
On your device only, so you get the same size and difficulty next time. Nothing is sent to a server.