How to play Sudoku

Sudoku is a logic puzzle played on a 9×9 grid. You don't need to be good at maths: it is all about placing numbers where they fit.

The rules

The grid is divided into 9 rows, 9 columns and 9 regions of 3×3 cells. Some cells already have a number. Your goal is to fill the rest so that:

• every row contains the numbers 1 to 9 exactly once,
• every column contains the numbers 1 to 9 exactly once,
• every 3×3 region contains the numbers 1 to 9 exactly once.

That's it. A well-made sudoku has a single solution, and you can always reach it by reasoning, without guessing.

A simple method to start

1. Pick a number and scan. Choose, for example, the number 1 and look at every region. If a region has no 1 yet, check which rows and columns already contain a 1: those lines are blocked for that region.
2. Look for the only free cell. When only one cell of the region can hold the number, write it down.
3. Repeat with the next number. Go through 1 to 9 and you will fill a good part of the board.
4. Use notes when you're stuck. Write the candidates of a cell as small notes and remove them as you place numbers. When a cell keeps a single candidate, that's its number.

Tip: start with the rows, columns or regions that are almost complete. Fewer gaps mean fewer options.

Choose your level

Sudoku 360 has five difficulty levels. The easier the level, the more numbers come pre-filled: the very easy level starts with 44 numbers on the board and the very hard one with only around 23. Every board has a single solution, so you can always solve it by logic. If you are new to the game, start with one or two stars and move up when you feel confident.

Play a very easy sudoku now and put these steps into practice.