Play free classic Sudoku online with easy, medium, hard, expert, and master puzzles. No download or sign-up required. Works smoothly on desktop, tablet, and phone.
This page opens a classic 9×9 Sudoku puzzle in your browser. Select a cell, enter a digit from 1–9, and keep every row, column, and 3×3 box unique. Use notes for candidates, undo to reverse a move, and hints when you want a gentle nudge.
Easy grids start with more givens so beginners can learn scanning. Medium and Hard remove clues and introduce longer logic chains. Expert and Master leave fewer anchors, so pencil marks and structured elimination matter more.
Notes store candidate digits inside a cell. Undo walks back recent moves without restarting. Hints reveal a logical next step when you are stuck. You can also open Print to take the current style of puzzle onto paper.