Classic number puzzle. Choose difficulty from easy to expert. Unlimited puzzles. Play instantly in your browser â no download, no account required.
Classic number puzzle. Choose difficulty from easy to expert. Unlimited puzzles. This is a free browser game â it works on Chrome, Firefox, Safari, and Edge without any installation. It also works on mobile browsers and Chromebooks.
Sudoku was popularized globally by Wayne Gould, who discovered the puzzle in a Tokyo bookshop in 1997 and spent six years creating a computer program to generate them. When The Times of London published the first Sudoku in 2004, it sparked a worldwide puzzle phenomenon. Today hundreds of millions of people solve Sudoku daily in print, apps, and browser games.
The logical techniques required to solve Sudoku span an enormous range of complexity. Naked singles â cells where only one digit is possible â are immediately obvious. Hidden singles â digits that can only go in one cell within a row, column, or box even if that cell shows multiple candidates â require slightly more attention. Beyond these basics, techniques like pointing pairs, box-line reduction, X-Wings, Swordfish, and forcing chains can solve progressively harder configurations.
Expert Sudoku puzzles are specifically designed to require advanced techniques that cannot be solved by simple scanning and elimination. A well-constructed expert puzzle has exactly one solution reachable through pure logic â no guessing required. Finding this solution using intermediate and advanced techniques is the challenge that dedicated players invest years studying.
Research confirms Sudoku's cognitive benefits. A 2019 study published in the International Journal of Geriatric Psychiatry found that older adults who regularly solved Sudoku and crosswords had brains functionally equivalent to those ten years younger. The combination of logical deduction, working memory, and pattern recognition exercises multiple cognitive systems simultaneously.
The browser version offers unlimited puzzles at every difficulty level with a hint system that reveals single cells rather than entire solutions. This graduated assistance lets you get unstuck without spoiling the solving experience for adjacent cells you have already deduced correctly.
A 2019 study found older adults who solved puzzles like Sudoku regularly had brains functionally equivalent to those ten years younger. The browser version offers unlimited puzzles with graduated hints that reveal single cells rather than full solutions.