How to play Sudoku

The goal

Playing

• Tap an empty cell, then tap a number to place it. Tapping the same number again clears the cell.
• The dark numbers are the puzzle’s clues and can’t be changed.
• The selected cell’s row, column and box are shaded, and matching numbers are highlighted.
• Each number key shows how many of that number are still to place.

Tools

• Notes: turn it on to pencil in possible numbers instead of placing them. Placing a number removes it from the notes in the same row, column and box.
• Erase clears the selected cell.
• Hint fills in the selected cell, or the next cell that needs one.
• Undo takes back your last change.

Mistakes

• A wrong number turns its cell red and adds to your mistake count. You can erase it or type over it.

Difficulty

• Easy: plenty of clues, and every step is a cell with only one possible number.
• Normal: fewer clues. Sometimes a number fits only one cell in its row, column or box.
• Hard: as few clues as possible. You’ll need to use notes and think a few steps ahead.
• Every puzzle is new and has exactly one solution. Your best times are kept separately for each difficulty.

Keyboard

• 1–9 to place a number, the arrow keys to move, Backspace to erase, N to switch notes on or off, and Ctrl or ⌘+Z to undo.

Questions

Strategy guides