Classic 9×9 Sudoku in your browser. No ads, no account, nothing to install — and after the first visit it works fully offline. Every puzzle is generated on your device with a guaranteed unique solution.
Four difficulty levels — easy, medium, hard and expert — graded by the hardest human solving technique each puzzle requires: naked and hidden singles, naked and hidden pairs, and pointing pairs. Pencil-mark notes, logical hints, undo/redo and automatic save/resume are built in.