Free sudoku online
So simple. So sudoku. One clean screen, three levels, and a new puzzle whenever you want one.
How to play
Fill the grid so that every row, every column and every 3×3 box holds the numbers 1 to 9 exactly once.
- Placing a number
- Tap an empty cell, then tap a number. The row, column and box light up, along with every matching number on the board.
- Mistakes
- A wrong number turns red and uses one of your three mistakes. The third one ends the game.
- Notes
- Turn Notes on to pencil small candidate numbers into a cell. They clear themselves when you place that number nearby.
- Erase and Undo
- Erase clears a wrong number or the notes in a cell. Undo steps back one move at a time.
- SOS
- Stuck? SOS fills in one cell for you. You get three per game.
- Timer
- The clock runs while you play. Pause stops it and hides the board.
Pick a level
Fewer starting numbers means a harder puzzle.
Questions
Is Sosudoku free?
Yes. It runs in your browser with nothing to install and no account to create.
Does every puzzle have one solution?
Yes. Each puzzle is made fresh on your device and checked to have exactly one solution.
What does the SOS button do?
It fills the cell you have selected with the right number. If no open cell is selected, it picks the one with the most solved neighbours. An SOS number can't be undone.
Is my game saved?
Yes. A game in progress and your best times are kept in this browser, so you can close the tab and pick up later. Clearing your browser data removes them.
Can I add it to my phone's home screen?
Yes. On iPhone, open the Share menu in Safari and choose Add to Home Screen. On Android, open the Chrome menu and choose Add to Home screen. It then opens full screen like an app.
Can I play with a keyboard?
Yes. Move with the arrow keys and type 1 to 9 to place a number. Backspace erases, U undoes, N switches Notes, H uses an SOS and P pauses.
Sosudoku is published by Mezware.