Game guide · CH12372
Learn the rules of Classic Sudoku
Open Classic Sudoku, check the instructions and begin a round. Fill all cells with 1–9; do not repeat a symbol in any row, column or region. Choose a clear next step rather than rushing through the instructions. Check the rule that explains your first action. Use the example below to understand a decision.
Bring this focus to a round
Watch the feedback after an action. A message can explain whether the input was accepted or whether a rule needs attention. Keep the objective visible.
What you need to achieve
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. Follow this game’s rules rather than another version’s.
How to proceed
- 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.
Input guidance
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. A careful first action helps you become familiar with the layout. Use the visible help when you are unsure of the next input.
An example to follow
On one puzzle in this collection, row 1, column 1 has 9 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry. Use the example as a guide rather than a substitute for reading your board. Consider the next action carefully.
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. 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.
A few questions answered
For my first round, 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.
As a new player, how do I control Classic Sudoku?
Here is the relevant explanation: 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?
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.
For a quick reminder, what should I watch out for in Classic Sudoku?
For clarity: 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.
For my first round, which play mode does Classic Sudoku use?
Here is the relevant explanation: The mode on this page is Solo. Same-device play uses one screen; this game library does not provide internet matchmaking.
Where should I start with Classic Sudoku?
For clarity: Select an empty cell. The original clues cannot be edited.
Before I begin, do I need an account or a payment for Classic Sudoku?
Here is the relevant explanation: 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?
Here is the relevant explanation: Use the Games list or save this game page in your browser bookmarks. The Guide is linked from the playing page.
While reading the Guide, how do I report an issue with Classic Sudoku?
The key detail is this: 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.
