Sudoku

Fill the 9x9 grid so that each row, column, and 3x3 box contains the numbers 1-9 exactly once. Use the given numbers as clues and apply logic to find the solution. No math required - just pattern recognition!

Notes are small numbers you can write in empty cells to track possible values. Turn on Notes mode and click numbers to toggle candidates. This helps in harder puzzles where you need to track multiple possibilities.

Start by scanning for obvious singles - cells where only one number fits. Then look for hidden singles where a number can only go in one place within a row, column, or box. For harder puzzles, use elimination techniques and track candidates with notes.

Red highlighting indicates a conflict - the same number appears twice in a row, column, or 3x3 box. Check your entries and correct the mistake. The game tracks your mistakes to help you improve!

Easy puzzles have more given numbers (~46) and can be solved with basic techniques. Expert puzzles have fewer clues (~23) and require advanced strategies. Medium and Hard fall in between, gradually introducing more complex solving patterns.