Free Online Sudoku

How to play

1. Choose the daily puzzle or a random sudoku, then a level: easy, medium, or hard.
2. Tap an empty cell and choose a number from 1 to 9.
3. Each digit can appear only once in every row, column, and 3x3 block.
4. Use notes mode to jot down small candidate numbers in a cell.
5. The sudoku is solved when all 81 cells are filled correctly. Mistakes and hints each cost 30 seconds.

Tips and tricks

• Look first at rows, columns, and blocks that already have seven or eight numbers filled in: the answer is almost given there.
• Work number by number: where can the 1 still go in this block? Often only one cell is left.
• For hard sudoku, notes are invaluable. If a cell has only one remaining candidate, it's certain.
• Never guess. A sudoku can always be solved by logic alone, and guessing costs time if you're wrong.

About Sudoku

Sudoku is the best-known number game in the world: a 9x9 grid, divided into nine 3x3 blocks, which you fill with the digits 1 to 9 so that each digit appears exactly once in every row, column, and block. No math required, just logic. Every sudoku here has a unique solution.

Our Zen Sudoku offers a new daily puzzle every day in easy, medium, and hard, the same one for every player around the world. Your time is your score: every mistake and every hint costs 30 seconds. You also get unlimited random sudoku at each level. Your progress, daily streak, and best times are saved in your browser.