Game guide · ZZDXKJ
Rules, controls and help for Classic Sudoku
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. Use the example below to understand a decision. Check the rule that explains your first action. Check the relevant rule before repeating a move.
Practice with a purpose
Read one step at a time and try it on the playing area. Match the instruction to the control you use. Use the example to check your reasoning.
What you need to achieve
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. Keep the controls in easy reach.
Follow these playing steps
- 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.
Choosing and moving on screen
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. Read the example below alongside these instructions.
Follow the example
On one puzzle in this collection, row 1, column 2 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. Read the matching step again.
A common point of confusion
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
On this playing page, what is the goal of Classic Sudoku?
Keep this in mind: Fill all cells with 1–9; do not repeat a symbol in any row, column or region.
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.
As a new player, what example helps explain Classic Sudoku?
The key detail is this: On one puzzle in this collection, row 1, column 2 has 9 in its solution. Read the clues on your current board before using that value; another puzzle can need a different entry.
For a quick reminder, what should I watch out for in Classic Sudoku?
Here is the relevant explanation: Notes are reminders, not final entries. A full board only counts as complete when it satisfies every rule.
While reading the Guide, what format does Classic Sudoku offer?
The key detail is this: 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.
Before I begin, where should I start with Classic Sudoku?
For clarity: 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?
The key detail is this: No player account or payment is needed. Game scores are recreational results, not cash prizes.
While learning, how can I find Classic Sudoku again?
Use the Games list or save this game page in your browser bookmarks. The Guide is linked from the playing page.
As a new player, how do I report an issue with Classic Sudoku?
Keep this in mind: 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.
