Game Objective
Fill the 9×9 grid with digits so that each column, each row, and each of the nine 3×3 subgrids that compose the grid (also called "boxes") contain all of the digits from 1 to 9.
Basic Rules
- Each row must contain the numbers 1-9 without repetition
- Each column must contain the numbers 1-9 without repetition
- Each 3×3 box must contain the numbers 1-9 without repetition
- Only the numbers 1 through 9 can be used
- You cannot change the numbers that are pre-filled in the puzzle (shown in blue)
Controls
- New Game: Start a new puzzle with the selected difficulty
- Check Solution: Verify if your current solution is correct
- Get Hint: Reveal the correct number for the selected cell
- Solve Puzzle: Let the computer solve the puzzle for you
- Reset Board: Clear all your entries and return to the original puzzle
- Number Pad: Click numbers to fill cells, or 'X' to clear a cell
Tips for Beginners
- Start by looking for rows, columns, or boxes that are almost complete
- Use pencil marks to note possible numbers for empty cells
- Look for numbers that can only fit in one particular cell
- Take your time and be patient - Sudoku is about logic, not guessing