Welcome to the free sudoku puzzle game Sudoku Challenge Online! This puzzle game is suitable for everyone, whether you’re a beginner or an expert player. With this game, you can train your skills and improve your concentration! Look at the numbers already placed on the and fill the empty slots with the right numbers. You can use the numbers 1 to 9. All rows, columns, and 3x3 blocks can only contain each number once. Don't worry if you get stuck, there are plenty of hints you can use to figure out these puzzles if you need and help.