How to play
- Fill the grid so every row, every column and every 3×3 box contains the digits 1 to 9 exactly once.
- Every puzzle has exactly one solution. Easy starts with 40 givens, Medium 34, Hard 28. Today's puzzle is the same for everyone on the same day.
- Tap a cell, then a digit on the keypad. Pencil marks jots candidates in a cell; placing a digit clears that candidate from its row, column and box.
- Show mistakes marks digits that do not match the solution. Hint reveals one cell (a wrong one first) — you get three per puzzle.
- The timer runs while the page is open and pauses when you leave. Best time is kept per difficulty. Puzzles save automatically.
- Keyboard: arrow keys move, 1–9 enters, Backspace or 0 erases, P toggles pencil marks.