Game guide · ZZQHMY
Read before your next round 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. Use the example below to understand a decision. Check the rule that explains your first action. Check the relevant rule before repeating a move.
Try a more deliberate round
After a move, check what changed. Decide which rule explains the new state before acting again. Keep the objective visible.
The purpose of your moves
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 steps to play
- 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.
Keyboard and screen 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. Use one clear input at a time.
Work through an example
On one puzzle in this collection, row 1, column 2 has 3 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. Notice the change in the playing area.
Keep this in mind
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.
Helpful answers for players
When I return, what is the goal of Classic Sudoku?
For clarity: 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?
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.
While reading the Guide, what example helps explain Classic Sudoku?
For clarity: On one puzzle in this collection, row 1, column 1 has 3 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry.
As a new player, what should I watch out for in Classic Sudoku?
Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule.
While learning, 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 a quick reminder, 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.
While learning, where should I start with Classic Sudoku?
Keep this in mind: Select an empty cell. The original clues cannot be edited.
For this browser game, do I need an account or a payment for Classic Sudoku?
For clarity: No player account or payment is needed. Game scores are recreational results, not cash prizes.
For this browser game, 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.
For this browser game, how do I report an issue with Classic Sudoku?
For clarity: 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.