Sudoku
Fill the 9×9 grid so every row, column and box holds 1–9. Four difficulties with notes and hints; one solution each.
Fill every row, column and 3×3 box with 1–9.
How to play
- Select a cell, then type 1–9 or use the number pad. Backspace or Clear empties it; arrow keys move.
- N toggles notes (small pencil marks). Placing a number clears that note from its row, column and box. H uses a hint.
- Easy shows wrong numbers in red and gives 5 hints. Hard allows 5 mistakes and 2 hints. Extreme has fewer givens, 3 mistakes, 1 hint and only marks rule clashes. Nightmare has the fewest givens, 3 mistakes, no hints and no clash marks.
- Every puzzle is generated and checked to have exactly one solution.