Game guide · 020GAY8
An introduction to playing Classic Sudoku
Read the aim of Classic Sudoku, then make your first move. 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. Check the rule that explains your first action. Use the example below to understand a decision.
Build familiarity through play
When a decision goes wrong, compare it with the common mistake described below. Start again only when you intend to leave the current round. Notice the feedback after each input.
Understand the aim
Fill all cells with 1–9; do not repeat a symbol in any row, column or region. An attractive position is not enough unless the goal is met. Take a moment to understand the current position.
Work through the instructions
- 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.
How your actions work
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. Use one clear input at a time.
Try this 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. Focus on why the action is allowed, not only its outcome. 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. Read the feedback to see why an action did not have the expected result. Locate the buttons and input area before beginning a long round. Use the on-screen labels to avoid an accidental restart.
Read these answers for extra help
For a quick reminder, what is the goal of Classic Sudoku?
Fill all cells with 1–9; do not repeat a symbol in any row, column or region.
When I return, how do I control Classic Sudoku?
The key detail is this: 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.
Before I begin, what example helps explain Classic Sudoku?
Here is the relevant explanation: On one puzzle in this collection, row 1, column 3 has 2 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry.
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?
Keep this in mind: 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 mode on this page is Solo. Same-device play uses one screen; this game library does not provide internet matchmaking.
For a quick reminder, where should I start with Classic Sudoku?
For clarity: Select an empty cell. The original clues cannot be edited.
As a new player, do I need an account or a payment for Classic Sudoku?
Keep this in mind: No player account or payment is needed. Game scores are recreational results, not cash prizes.
As a new player, how can I find Classic Sudoku again?
The key detail is this: Use the Games list or save this game page in your browser bookmarks. The Guide is linked from the playing page.
On this playing page, how do I report an issue with Classic Sudoku?
Use the contact form and include the game name, browser, device and the actions that led to the issue. Do not send passwords or payment details.