How to Play Sudoku
Sudoku is a logic puzzle. No maths, no guessing — just three simple rules and the numbers 1 to 9.
The Grid
A Sudoku puzzle is a 9×9 grid divided into nine 3×3 boxes. Some cells are pre-filled as clues. Your job is to fill every empty cell so each row, column, and box contains the digits 1 through 9 exactly once.
The blue box shows one of the nine 3×3 regions — it must contain 1–9.
① Every row must contain 1 to 9
Each of the 9 horizontal rows must have every digit from 1 to 9, each appearing exactly once. No digit can repeat in the same row.
② Every column must contain 1 to 9
Each of the 9 vertical columns must also hold every digit from 1 to 9, each exactly once.
③ Every 3×3 box must contain 1 to 9
Each of the nine 3×3 boxes must contain every digit from 1 to 9 exactly once — just like rows and columns.
All three rules apply at once — every move you make must satisfy the row, the column, and the box it belongs to.
How to Solve
A well-formed Sudoku never requires guessing — pure logic is always enough.
- 1 Look for cells where only one digit can legally go — it must not appear in the same row, column, or box.
- 2 Scan each row, column, and box to find digits that can only fit in one remaining empty cell.
- 3 Work through the grid, using each new number you fill in to unlock further cells.
Difficulty Levels
This game offers three difficulty levels that affect how many clues are given and what aids are available.
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