A free math puzzles game from Razzle Puzzles that tests your arithmetic and logic. If you like Sudoku logic puzzles, you will love Calcudoku. About Calcudoku Math Puzzles: Every Calcudoku has a single solution that can be reached logically. Similar to Sudoku, fill in the grid such that no two digits repeat in any column or row. Use the shapes in the grid as your guide. Each shape contains a number equaling the product of the shapes' digits. For example a shape with three cells containing the number 6 may have cell values 1, 2 and 3, as 1.2.3 = 6. Challenge yourself further with larger grids, up to 9x9 size. This free puzzle game contains features to help you solve the math-based logic puzzles including an unlimited number of hints and checks in case you get stuck. A calculator tool is available to help with multiplication and division against large numbers. Additionally all games are automatically saved and restored so you can stop and restart with ease. You can play Calcudoku by Razzle Puzzles on your phone and tablet. Calcudoku is also known as Mathdoku and was originally invented in 2004 by Japanese math teacher Tetsuya Miyamoto. Play and print Calcudoku math puzzles on your computer and find more puzzles at RazzlePuzzles.com.