How to Play Sudoku for Beginners
The three essential rules
Sudoku uses a 9 × 9 grid divided into nine smaller 3 × 3 boxes. Fill every empty cell with a digit from 1 to 9. Each row, each column and each 3 × 3 box must contain every digit exactly once. You never need arithmetic: the challenge is logical deduction.
Start with the obvious cells
Scan a row containing many given digits. Compare its missing digits with the digits already in the crossing columns and in the corresponding box. If only one candidate remains for a cell, write it in. Repeat the process across the grid.
Use pencil notes wisely
When a cell allows two or three possible digits, record them as notes. Do not guess if there is no clear next move. As you place certain digits, revisit your notes and remove candidates that are no longer possible.
Finish with a check
A complete valid Sudoku has no repeated digit in any row, column or box. Use the optional Check button only when you want feedback; each check or hint adds five seconds to your game time.