Sudoku
Test your logic with classic Sudoku puzzles across multiple specialized difficulty levels.
Sudoku Grid
Errors
0Puzzle Solved!
Incredible logic skills. Ready for another?
How to Play
Fill the 9x9 grid so that each column, each row, and each of the nine 3x3 subgrids contains all of the digits from 1 to 9.
Difficulty
Game Tools
RankWox Local Processing
Free Online Sudoku – Number Logic Puzzle Game
Challenge your brain and improve your cognitive skills with our Free Online Sudoku Game. Originating from Japan, this classic number-placement puzzle requires no math skills—just pure logic. Choose from Easy, Medium, or Hard difficulty levels, use our interactive digital interface for immediate error tracking, and solve procedurally generated grids right in your browser.
Dynamic Difficulty
Whether you are a beginner looking for a relaxing puzzle or a master wanting minimal clues, our generation engine customizes the board density.
Interactive Helpers
Stuck on a tricky row? Click the Hint button to reveal a correct number, or use the interactive numpad if you don't have a keyboard.
Instant Feedback
Typing an incorrect duplicate number in a row or square immediately highlights the cell red, preventing cascading logical errors.
Sudoku FAQs
Do I need to be good at math to play?
Not at all! Sudoku is purely a game of logic and pattern recognition. The numbers 1 through 9 could just as easily be replaced with shapes or colors.
Why did my number turn red?
If a number turns red, it means you've placed a digit that already exists in that specific row, column, or 3x3 block, violating the core rule.
How does the hint system work?
When you select an empty cell and click "Use Hint", the background engine solves the puzzle array and injects the absolute correct digit into that spot.
Is this playable on a phone?
Yes. We built a dedicated on-screen number pad specifically so mobile users can tap cells and enter digits without opening their phone keyboard.