Sudoku
Play a unique 9×9 puzzle. Your current game and best unassisted times stay on this browser.
Runs in your browser — nothing is uploadedArrow keys move the selection. Digits enter numbers; Delete or 0 erases. N toggles notes in the game. Clues stay fixed.
How to use Sudoku
- Choose a difficulty and start a new puzzle.
- Select a cell, enter a digit or toggle pencil notes; use undo and erase as needed.
- Pause or return directly to this page to continue your saved game.
Questions
How is difficulty determined?
Easy completes with naked singles. Medium also needs hidden singles. Hard needs up to five branching decisions; Expert needs more. This is the measured work of this solver, not a standardized human difficulty rating.
Are puzzles and progress uploaded?
No. Puzzles and solving run locally. Game progress and best times are saved only on this browser and never trigger homepage editor recovery.
Does the solver explain each step?
No. It reports actual validity and solution counts, without inventing solving explanations.