How to play Sudoku
Sudoku is the classic number puzzle: fill every empty square so that each row, column and 3x3 box contains the digits 1 to 9 exactly once. Every puzzle is generated fresh on your device and has exactly one solution that you can reach by logic, no guessing needed.
Pick one of five levels, from a relaxed Easy grid to a Master puzzle with only a handful of clues. Tap a cell and a digit, or use the keyboard. Switch on Notes to pencil in candidates, undo any move, erase a wrong entry, and use up to three hints per game: each hint places a digit and explains the reasoning behind it. Wrong digits count as mistakes, and the third one ends the game, although an optional video can give you a second chance.
Solve faster and cleaner for a higher score: completing a row, column or box gives a bonus, streaks of correct digits multiply the points, and a perfect game pays extra. A daily puzzle keeps your streak going. Your unfinished game, best times and scores are saved on your device.
Controls
Click a cell, then a number on the pad (or press 1-9). N: notes on/off. Backspace: erase. U or Ctrl+Z: undo. H: hint. Arrow keys: move. P or Esc: pause. M: sound.
Tap a cell, then tap a number. Use Notes to pencil in candidates, Undo and Erase to fix a move, and Hint when you are stuck.
FAQ
Is there always exactly one solution?
Yes. Every puzzle is checked to have a single solution, and Easy to Hard can be solved with logic alone, without guessing.
What happens when I make a mistake?
A digit that does not belong counts as a mistake and turns red. Erase it and try again. After three mistakes the game is over, but you can watch an optional video for a second chance.
How do hints work?
You get three hints per game. A hint fills one cell and tells you why that digit fits. When they run out you can watch an optional video to get one more.
What is the daily puzzle?
One puzzle per day, the same for everyone on that date. Solve it to build a daily streak.
Is Sudoku free?
Yes. It is free to play in your browser, with no download and no account.
Can I play on my phone?
Yes. It runs on phones, tablets and computers. Tap a cell, then tap a number. Use Notes to pencil in candidates, Undo and Erase to fix a move, and Hint when you are stuck.