About Sudoku
Sudoku is one of the most enduring logic puzzles ever designed, and this browser version delivers the full classic experience with a clean, easy-to-use interface. The objective is to fill a nine-by-nine grid so that every row, every column, and every three-by-three box contains each digit from one to nine exactly once. No math is involved — it is pure deductive reasoning, making it equally accessible to young players and seasoned puzzle veterans. Each puzzle begins with a set of pre-filled numbers that provide the logical foothold you need. Difficulty ranges from beginner grids that guide you gently through the logic to expert puzzles that demand complex elimination chains and genuine mental effort.
How to Play
Click or tap an empty cell to select it, then enter a number from one to nine using the keyboard or on-screen number pad. Use the pencil or note mode to mark candidate numbers in cells you are unsure about. A number is valid only if it does not already appear in the same row, column, or three-by-three box.
Tips & Tricks for Sudoku
- Start with rows, columns, or boxes that already contain the most filled numbers, as they leave fewer possibilities for remaining empty cells.
- Use pencil marks to write candidate numbers in uncertain cells, then eliminate candidates as you fill in neighboring cells.
- Look for a single number that can only fit in one cell within a particular row, column, or box — this naked single technique solves the majority of beginner and intermediate puzzles.
Frequently Asked Questions
Is this Sudoku game free to play?
Yes, it is completely free with no account or download required — open the game in your browser and start playing instantly.
Can I play Sudoku on my phone or tablet?
Yes, the game is fully browser-based and works on any device with a modern browser, including smartphones and tablets.
Are there different difficulty levels available?
Yes, the game offers multiple difficulty tiers so beginners can learn the mechanics while experienced players can challenge themselves with harder grids.