2024-June 🌻 Happy Summer! 🏖️

Kaleidoscope Logic Puzzles (Summer 2024, Puzzlewright Press) is my first variety slitherlink book, and my most beautiful book to-date. It is spiral-bound, and contains 124 puzzles, including both classic and variety Slitherlink puzzles. These lovely puzles include several unique full-page tessellations that I have not published elsewhere. If you are new to Slitherlink, you'll appreciate the tutorials which cover both classic and non-square-grid Slitherlink puzzles.

Free Beginner Calcudoku Puzzles

Here are hundreds of free Calcudoku puzzles suitable for printing. These Inkies do not use multiplication and division (click here for those). Inkies have the same rules as the famous puzzles created by Tetsuya Miyamoto. They are variously called KenKen®, Mathdoku, Calcudoku, and Web Kendoku. Each Inky puzzle has only one unique solution.


Fill in the blank squares so that each row and each column contain all of the digits 1 thru 4 (or whatever the size of the puzzle is).

The heavy lines indicate areas (called cages) that contain groups of numbers that can be combined (in any order) to produce the result shown in the cage, with the indicated math operation (plus or minus).

Numbers in cages may repeat, as long as they are not in the same row or column.

Take a look at the answers page if you get stuck!

Thanks to Simon Tatham, whose code formed the starting point for this collection.