Fill every row, column and 3×3 box with digits 1–9. Auto-notes, hints, and mistake tracking included. Three difficulty levels!
🌱
Easy
40 clues
⚡
Medium
32 clues
💀
Hard
25 clues
⏱
Time
0:00
❌
Mistakes
0 / 5
💡
Hints Left
3
📊
Progress
0%
How to Play Sudoku
Fill the 9×9 grid so that every row, every column, and every 3×3 box contains the digits 1 through 9 with no repeats. Click a cell to select it, then click a number from the number pad to fill it in.
Notes mode — toggle Notes ON to pencil in small candidate numbers in a cell when you're not sure. Hints — stuck? Use a hint to reveal the correct number for the selected cell (3 hints per game). You have 5 mistakes allowed before the game ends.
Sudoku — FAQs
What is the fastest way to solve Sudoku?
Start by finding rows, columns, or boxes where only one number is missing — those are free squares. Then use the process of elimination: for each empty cell, rule out numbers already in the same row, column, and box. Notes mode helps you track candidates.
Does every puzzle have a unique solution?
Yes — every puzzle generated in this game has exactly one valid solution, which is how a proper Sudoku puzzle should work.
What happens if I make 5 mistakes?
The game ends after 5 mistakes. Start a new game with the New Game button. Try Notes mode to avoid guessing!
Can I use the keyboard to play?
Yes! Click a cell to select it, then press 1–9 on your keyboard to fill in a number. Press Delete or Backspace to erase. Press N to toggle Notes mode on and off.