Calcudoku: Free KenKen-Style Math Puzzles
Calcudoku mixes Sudoku with arithmetic. Put each number once in every row and column, and make every cage hit its target. Start with 3 × 3 addition, add subtraction at 4 × 4, then use all four operations at 5 × 5 and 6 × 6. Every puzzle has one solution and can be solved without guessing.
- Calcudoku for Kids3 × 3, addition onlyAges 6–8 (Grades 1–2)
- 4×4 Calcudoku4 × 4, + and −Ages 7–10 (Grades 2–4)
- 5×5 Calcudoku5 × 5, + − × ÷Ages 9–12 (Grades 4–6)
- 6×6 Calcudoku6 × 6, + − × ÷Ages 10 and up
- Daily CalcudokuA new 5 × 5 every dayAges 9 and up
Questions and answers
What is Calcudoku?
A number puzzle where each row and column uses the numbers 1 to n exactly once, and outlined groups of squares (cages) must combine to a target using +, −, × or ÷. The same kind of puzzle is sold as KenKen® (a trademark of Nextoy, LLC) and is also called MathDoku.
Is Calcudoku good for learning math?
Yes. Every clue is an arithmetic question in reverse: “which two numbers multiply to 12?” Children practise number facts, factors and checking their work while solving a logic puzzle.
Which size should I start with?
Start with 3 × 3 Calcudoku for kids if you’re new, or 4 × 4 if you’re happy with addition and subtraction. 5 × 5 adds multiplication and division, and 6 × 6 is the biggest challenge.