How to play Sudoku
Fill every row, column and 3×3 box with digits 1 to 9. Choose a difficulty and use notes to reason it out.
- Each row, column and 3×3 square must contain the numbers 1–9 exactly once.
- Select an empty square, then choose a number. Toggle Notes to pencil in possibilities.
- Check highlights mistakes; Hint reveals the correct number in one cell. Each puzzle has one solution.