How to Play Classic Sudoku

THE PLAYBOOK · RHEFM

How to play Classic Sudoku

Try Classic Sudoku at your own pace and keep its objective in view. Fill all cells with 1–9; do not repeat a symbol in any row, column or region. Use the example below to understand a decision. Keep the instructions close while learning this activity. Check the relevant rule before repeating a move.

A careful first round

Before your first action, say what you are trying to achieve. Then compare the result with the goal. Use the example to check your reasoning.

Your goal

Fill all cells with 1–9; do not repeat a symbol in any row, column or region. Read that aim before choosing your first action. Try to explain the aim in your own words.

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. On a smaller screen, keep the active part of the board within view. Avoid pressing the same control repeatedly while a move is being processed.

A useful example

On one puzzle in this collection, row 1, column 2 has 9 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry. Apply the same reasoning to the position in your own round. Verify the rule before continuing.

Watch out for this

Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule. Check the rule before repeating the action. Locate the buttons and input area before beginning a long round. Use the on-screen labels to avoid an accidental restart.

Common questions