How to play
- Pick a level: easy puzzles have about 40 given digits, expert ones about 24. Every puzzle is generated in your browser and checked to have exactly one solution.
- Select a cell by tapping it (or with the arrow keys) and enter a digit with the number pad or the keys 1–9. ⌫ or Delete clears it.
- Notes (✎ or the N key) let you pencil in candidates. Placing a digit removes it from the notes in the same row, column and box.
- Stuck? Turn on “Show mistakes”, use 💡 Hint to fill one cell, or ↶ Undo. Games with hints don’t count for the best time.
Your game is saved automatically, so you can close the page and continue later. The small number on each pad key shows how many of that digit are still missing.