Sudoku

How to play Sudoku

Fill the nine-by-nine grid so every row, column, and 3×3 box contains the digits 1 through 9 exactly once.

Rules

1. No digit may repeat in any row, column, or 3×3 box.
2. Dark numbers are givens. They cannot be changed.
3. Every Sudoku puzzle has exactly one solution.

Tips

• Start with rows, columns, or boxes that already hold many digits.
• If a number can go in only one cell of a box, place it there.
• Scan one digit at a time across the board instead of filling cells at random.
• Use Check to mark mistakes, Hint to fill one empty cell, and Undo if you change your mind.
• Turn on Notes to pencil small candidate digits in a cell. Tap a number again to remove it.