Play Sudoku Online

About Sudoku

Sudoku is the number-placement puzzle that needs no arithmetic at all — only logic. Fill the 9x9 grid so that every row, every column and every 3x3 box contains the digits 1 through 9 exactly once. Multiple difficulty levels mean it works as a quick warm-up or a serious sit-down puzzle.

How to play

• Tap an empty cell to select it.
• Choose a digit from 1 to 9 to place it.
• Every row, column and 3x3 box must contain each digit exactly once.
• Use pencil notes to track candidates in tricky cells.
• Fill the whole grid correctly to finish.

Controls: Tap a cell, then tap a number. Keyboard digits work on desktop.

Tips

• Start with the rows, columns and boxes that already have the most digits filled in.
• If a digit can only go in one cell of a box, place it — that is the fastest scanning technique.
• Use notes rather than guessing; a wrong guess in Sudoku costs more time than it saves.

Do I need to be good at maths?

No. Sudoku uses digits as symbols — there is no adding or counting involved, only logic.

Are there difficulty levels?

Yes, you can choose an easier or harder puzzle before you start.

Is it free?

Yes — free, browser-based, no download or account.