Free browser-based brain puzzle
Sudoku Online
Play Sudoku online for free with easy, medium and hard puzzles. Fill the grid, use hints when stuck, track your timer and mistakes, beat your best score and share your Sudoku result.
Score
1200
Filled
0/81
Time
0s
Sudoku Board
Select a cell, then enter 1–9. Turn on notes for pencil marks.
Select a cell, then press 1–9 on keyboard or tap the number pad below.
Recent Results
Your last 10 Sudoku results are saved locally in this browser.
Sudoku tips
Scan rows and columns
Look for missing numbers in each row, column and 3×3 box before guessing.
Use notes carefully
Turn on notes mode to add candidate numbers before placing a final answer.
Use hints only when stuck
Hints help when stuck, but they reduce your final score.
How to play Sudoku
Choose difficulty
Start easy, then try medium or hard.
Select a cell
Tap any empty cell in the 9×9 grid.
Enter number
Use the number pad to place numbers 1 to 9.
Finish puzzle
Complete all cells correctly to save your result.
Train logic and focus
Sudoku is a classic logic puzzle that rewards patience, observation and structured thinking.
Play at your level
Choose easy puzzles for warm-up or hard puzzles when you want a stronger brain challenge.
Track improvement
Timer, mistakes, hints and recent results help you replay and improve your solving speed over time.
Sudoku FAQ
Is this Sudoku game free?
Yes. SmartTools Sudoku is free to play online with no signup required.
How do I play Sudoku?
Fill the 9×9 grid so every row, column and 3×3 box contains numbers 1 to 9 without repeating.
Does this Sudoku game have difficulty levels?
Yes. You can play easy, medium and hard Sudoku puzzles.
Are scores saved?
Your best score, streak and recent results are saved locally in your browser. They are cleared if you clear browser data.
Can I play Sudoku on mobile?
Yes. The Sudoku board and number pad are designed to work well on phones, tablets and desktop screens.
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