logic puzzle
How to play Sudoku
Quick answer: Sudoku is a number logic puzzle where every row, column and 3x3 box must contain digits 1 to 9 exactly once.
Sudoku rules
Choose a difficulty, select an empty cell and enter a number. Fixed clues cannot be changed. The round is complete when every cell is filled and the board satisfies all Sudoku rules.
Controls
Tap or click a cell, then choose a number. Keyboard number keys also work on desktop. Use notes to mark candidates when you are solving by deduction.
Scoring and ranking
Sudoku rankings favor completed boards with fewer mistakes and faster times within the selected difficulty.
Strategy tips
- Start with rows, columns or boxes that already contain many digits.
- Use notes to avoid guessing when several numbers are possible.
- Check a candidate against its row, column and 3x3 box before committing.
FAQ
Is Sudoku a math game?
No. Sudoku uses digits, but the skill is logical placement rather than arithmetic.
What is the best first move?
Scan for rows, columns or boxes with only one or two missing numbers.
Can I play Sudoku on mobile?
Yes. The board and number controls are designed for touch play.