Welcome to Calcudoku!

Welcome to Puzzle Baron's Calcudokus! Whether you know them as Calcudoku, Mathdoku or KenKenTM, we've got thousands and thousands of unique puzzles here for you to solve. You can play for fun, or register a free account and compete against other players for the Calcudoku Hall of Fame!

How to Play

Calcudoku is just like Sudoku - you must enter numbers into a grid in such a way so that no number is repeated in any row or column. But Calcudoku puzzles have an added mathematical component! Each grid is split up into smaller sections of 2 or more squares, and each of those sections has an arithmetic equation attached to it (either addition, subtraction, multiplication or division). You must complete the grid so that the numbers is each section equal the mathematical formula assigned to it.

If you're new to Calcudoku puzzles, start off on an easy 4x4 puzzle and work your way up to the larger/harder ones. The same types of solving methods used in regular Sudoku puzzles will come in handy with these as well. Good luck!

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Why Register a Free Account?

You'll never have to register an account to play on this site, but there are several reasons you may want to play as a registered user:

If any or all of the above features sound good to you, click on the button below to register for a free account:

Register for Free »

Competition Timer
  • MagicMoon13 MagicMoon13 set a new record of 214 seconds on puzzle #10803 June 25, 2022, 6:20 pm
  • MagicMoon13 MagicMoon13 set a new record of 92 seconds on puzzle #10948 June 25, 2022, 6:16 pm
  • penn0502 penn0502 set a new record of 134 seconds on puzzle #11752 June 25, 2022, 2:23 pm
  • MagicMoon13 MagicMoon13 set a new record of 171 seconds on puzzle #10332 June 25, 2022, 1:37 pm
  • MagicMoon13 MagicMoon13 set a new record of 93 seconds on puzzle #10277 June 25, 2022, 1:32 pm
  • WKDJAN WKDJAN set a new record of 258 seconds on puzzle #14394 June 25, 2022, 1:29 pm
May's Winners