Play Free Sudoku Online
Solve a new 9x9 Sudoku puzzle for free. Each puzzle is randomly generated—start from easy to hard difficulty and test your logic-solving skills as you fill the grid.
Fill in the empty cells using the numbers 1 to 9, then click Submit Puzzle to check your answer.
What is Sudoku?
Sudoku is a logic puzzle played on a 9x9 grid. The grid is divided into nine 3x3 boxes, and the goal is to place the numbers 1 to 9 so that each row, column, and box contains every number exactly once.
A good Sudoku puzzle can be solved by reasoning, not arithmetic. The given numbers are clues; each empty cell is filled by narrowing down which numbers can legally fit.
How to play Sudoku
- Start with the fixed numbers already shown in the grid.
- Choose an empty cell and check its row, column, and 3x3 box.
- Enter a number from 1 to 9 only when it does not already appear in those three areas.
- Keep filling cells until every row, column, and box is complete.
- Click Submit Puzzle to check the finished grid.
Sudoku strategies to try
- Scan for missing numbers. Pick a number and look across nearby rows, columns, and boxes to see where it can still fit.
- Use candidates. When a cell has more than one possible answer, note the legal options and come back when another clue removes one.
- Find singles first. A naked single is a cell with only one possible number. A hidden single is the only place a number can go in a row, column, or box.
- Work one box at a time. Finishing a 3x3 box often gives useful clues for the crossing rows and columns.
- Avoid guessing early. If you are stuck, look for a new constraint before trying a number. You can also use the 9x9 Sudoku solver to check a puzzle from another source.