Learn Sudoku
How to Play Sudoku: A Beginner's Guide
New to Sudoku? Learn the three rules, how to make your first moves, when to use notes, and how to solve without guessing.
Read Article →CalmSudoku Learning Center
Sudoku Guides & Strategies
Learn the rules, practice a repeatable solving process, and progress from beginner singles to advanced eliminations. Each guide links directly to a puzzle where you can use the technique.
Today’s Daily Sudoku
One shared, ad-free puzzle each day. Finish it to build a private streak on this device.
Learn Sudoku
Sudoku Rules: Everything You Need to Know
A clear reference to Sudoku's core rules, common misconceptions, valid moves, and how to know when a puzzle is complete.
Read Article →Sudoku Strategy
Sudoku Tips and Strategies for Beginners
Practical Sudoku tips that help beginners move from random searching to a repeatable, logical solving process.
Read Article →Sudoku Strategy
How to Solve Hard Sudoku Puzzles
A practical path for solving harder Sudoku puzzles without blind guessing, from disciplined candidates to advanced eliminations.
Read Article →Sudoku & the Brain
Does Sudoku Help Your Brain? What the Research Says
Sudoku is mentally demanding, but what does research actually show? A careful look at working memory, reasoning, cognitive training, and overclaims.
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