How to Play Classic Sudoku

THE PLAYBOOK · SXSRCB

How to play Classic Sudoku

Choose a round of Classic Sudoku and settle into its rules. Fill all cells with 1–9; do not repeat a symbol in any row, column or region. Look at what changes after your first action. Identify the playing area and the controls you need. Choose a clear next step rather than rushing through the instructions.

Make the controls familiar

Locate the buttons and input area before beginning a long round. Use the on-screen labels to avoid an accidental restart. Refer to the controls when needed.

Your goal

Fill all cells with 1–9; do not repeat a symbol in any row, column or region. The feedback beside the game helps you follow the round. Take a moment to understand the current position.

Step by step

1. Select an empty cell. The original clues cannot be edited.
2. Choose a symbol from the number pad, or type it on a keyboard.
3. Turn Notes on to record candidate symbols without committing an answer.
4. Use Check entries to check your filled values. Hint reveals one value from the verified solution.
5. Complete the board, or choose New puzzle for another board.

Controls

Tap or click a cell and use the number pad. Keyboard: arrows select cells; digits (and A–G on 16×16) enter values; Backspace erases. Keep the playing area visible while using these controls. Check any mode label before starting.

A useful example

Before filling a cell, compare the symbols already used in its row, column and 3 × 3 region. A candidate must be absent from all three. Apply the same reasoning to the position in your own round. Take a moment to compare.

Watch out for this

Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule. A different version of the game may use a different rule. When a decision goes wrong, compare it with the common mistake described below. Start again only when you intend to leave the current round.

Common questions