About Sudoku: Fill a 9×9 Grid with Numbers 1 to 9

Sudoku is a number-placement puzzle played on a 9×9 grid divided into nine smaller 3×3 squares, giving 81 cells in total. At the start of each puzzle, some cells already contain numbers from 1 to 9, and the goal is to fill every remaining cell so that each digit from 1 to 9 appears exactly once in every row, every column, and every 3×3 square. Multiple difficulty levels are available to choose from, and mistakes are something to watch out for as the puzzle progresses.

How to Play Sudoku

Select any empty cell to target it, then select the number to place there. Before committing to a number, the Notes button lets you mark candidate digits in a cell without placing them as a final answer — useful for tracking possibilities across rows and columns.

Controls

• Click on a cell: Select the cell to fill
• Click on a number: Place that number in the selected cell
• Click "Notes" button: Toggle note mode to mark possible numbers without placing them

Games You Might Like

For more number-based logic challenges, Math Crosswords swaps letters for equations that intersect across a grid, with every level having exactly one solution — a satisfying match for Sudoku's single-answer structure. If you enjoy working through large collections of puzzles, Crosswords: Big Collection offers over 800 levels and a daily puzzle with a streak system, keeping the brain-training habit going. Hidden Objects shifts the focus to visual observation and careful scene-scanning, a different kind of puzzle patience that Sudoku fans often appreciate.

Browse the full Educational games catalogue for more logic and learning titles, or explore the Puzzle games and Number games sections for additional grid-based and numerical challenges.