Learn the rules and become a Sudoku master.
Fill the 9x9 grid with numbers 1 to 9.
Each row must contain the numbers 1 to 9 without repeating any.
Each column must contain the numbers 1 to 9 without repeating any.
Each 3x3 block must contain the numbers 1 to 9 without repeating any.
✔ Start by looking for rows or columns that already have many numbers placed.
✔ Look at the 3x3 blocks to rule out possible positions.
✔ If you're torn between several options, move on to another part of the board.
✔ Practice greatly improves your speed and logic.