BEGINNER GUIDE
How to Play Sudoku
Sudoku is a logic puzzle played on a 9×9 grid. Your goal is to fill every empty cell using digits 1 through 9 without duplicates in a row, column or 3×3 box.
Step 1: scan for missing digits
Choose a row, column or box with many givens. List which digits are missing and see which empty cells can accept them.
Step 2: use candidates
If a value is not certain, record the possible digits as notes. Candidates shrink as nearby values are placed.
Step 3: repeat without guessing
Alternate between rows, columns and boxes. A valid Sudoku can be solved by deductions rather than random trial.