THE PLAYBOOK · ZRZCH
The Classic Sudoku playbook
Classic Sudoku gives you a focused activity to play in your browser. Fill all cells with 1–9; do not repeat a symbol in any row, column or region. Check the relevant rule before repeating a move. Compare the starting position with the example in the Guide. Use the example below to understand a decision.
A focus for your next round
Take enough time to read a new position. If a game has a timer, learn its controls first rather than searching for them during the round. Notice the feedback after each input.
The objective of a round
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. Start with a deliberate move.
The playing sequence
- Select an empty cell. The original clues cannot be edited.
- Choose a symbol from the number pad, or type it on a keyboard.
- Turn Notes on to record candidate symbols without committing an answer.
- Use Check entries to check your filled values. Hint reveals one value from the verified solution.
- Complete the board, or choose New puzzle for another board.
Making selections and moves
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. Use the control method described here for this activity. Use one clear input at a time.
See how the rules apply
On one puzzle in this collection, row 1, column 3 has 9 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry. Focus on why the action is allowed, not only its outcome. Check the stated objective.
Keep this in mind
Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule. Take a moment to reassess the position before continuing. When a decision goes wrong, compare it with the common mistake described below. Start again only when you intend to leave the current round.
Questions about this game
Before I begin, what is the goal of Classic Sudoku?
The key detail is this: Fill all cells with 1–9; do not repeat a symbol in any row, column or region.
On this playing page, how do I control Classic Sudoku?
Keep this in mind: 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.
What example helps explain Classic Sudoku?
Here is the relevant explanation: 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.
As a new player, what should I watch out for in Classic Sudoku?
Keep this in mind: Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule.
As a new player, what format does Classic Sudoku offer?
Play using the solo mode shown on this page. Read the controls before starting a new round.
Before I begin, which play mode does Classic Sudoku use?
The key detail is this: The mode on this page is Solo. Same-device play uses one screen; this game library does not provide internet matchmaking.