🔢 Sudoku
Fill every row, column and 3×3 box with digits 1–9. No repeats allowed.
✅ How to Play Sudoku
- Tap a blank cell to select it, then tap a number on the pad to fill it in.
- Every row, every column and every 3×3 box must contain digits 1–9 with no repeats.
- Use Notes mode to pencil in candidate numbers — great for harder puzzles.
- Made a mistake? Use Undo to step back, or Erase to clear the selected cell.
- Stuck? Tap Hint to reveal one correct digit (use sparingly!).
Common Questions About Sudoku
What's the difference between Easy, Medium and Hard?
Easy removes ~35 digits from the solved grid, leaving plenty of obvious moves. Medium removes ~46, requiring more deduction. Hard removes ~52+, needing advanced techniques like naked pairs and pointing pairs.
What does Notes mode do?
Notes mode lets you pencil in small candidate digits inside a cell — just like writing lightly in a paper puzzle. Tap Notes to toggle it on, then tap any number to add or remove it as a candidate. Tap a confirmed number normally when you're sure.
Is my best time saved?
Yes — your fastest completion time per difficulty is saved automatically in your browser. Return on the same device and browser to try to beat it.
How many hints can I use?
There's no hard limit on hints — but each hint is counted and shown so you can challenge yourself to use fewer next time. Completing a puzzle with 0 hints is the true win!
Can I play on mobile?
Yes — the board and number pad are fully touch-optimised. Tap any cell then tap a number to fill it in. The board scales to fit any screen size.
Sudoku Strategy Tips
| Technique | How It Works |
|---|---|
| 🔍 Single Candidate | If only one digit can go in a cell, place it immediately |
| 📦 Box Scan | Check which digits are missing in each 3×3 box first |
| ↔️ Naked Pair | Two cells in a row/col/box with only the same two candidates — remove those from all others |
| 👉 Pointing Pair | If a candidate only appears in one row/col within a box, eliminate it from the rest of that row/col |
| ✏️ Use Notes | Always pencil in candidates on Hard before committing to a digit |
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