Sudoku
MediumWhat is Sudoku?
Sudoku is a logic-based number placement puzzle. The objective is to fill a 9x9 grid so that every row, column, and each of the nine 3x3 sub-grids contains the digits 1 through 9 exactly once.
How to Use This Site
Click any empty cell to select it, then press a number key or tap a button on the number pad. Use Notes mode to pencil in candidates. Arrow keys move between cells. Press Backspace to erase.
Three Difficulty Levels
Easy removes 36 cells and is ideal for beginners. Medium removes 46 and requires some deduction. Hard removes 54 cells and demands advanced logical techniques and patience.