Game guide · SXSMQZJ
How to play Classic Sudoku
Use a short break to learn the rhythm of Classic Sudoku. 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. Check the rule that explains your first action. Use the example below to understand a decision.
Try a more deliberate 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. Make the next step deliberately.
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. Try to explain the aim in your own words.
Step by step
- 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.
The controls to know
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. Read the example below alongside these instructions.
An example before you play
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. Focus on why the action is allowed, not only its outcome. Notice the change in the playing area.
Check this before moving on
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. 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
While learning, what is the goal of Classic Sudoku?
Fill all cells with 1–9; do not repeat a symbol in any row, column or region.
While reading the Guide, 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?
For clarity: 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.
For this browser game, 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.
When I return, what format does Classic Sudoku offer?
Play using the solo mode shown on this page. Read the controls before starting a new round.
As a new player, 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.
While learning, where should I start with Classic Sudoku?
The key detail is this: 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.
While learning, how can I find Classic Sudoku again?
Keep this in mind: Use the Games list or save this game page in your browser bookmarks. The Guide is linked from the playing page.
Before I begin, 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.