Difficulty Rating
A system that classifies puzzle difficulty based on the complexity of techniques required to solve it.
Difficulty rating is a system for objectively classifying the difficulty of Sudoku puzzles. It analyzes not just the number of givens but the complexity of techniques required for the solution, categorizing puzzles from Easy to Extreme.
Rating Criteria
A human solving process is simulated against the puzzle to determine which techniques are needed. If only Naked Singles are required, it is rated Easy; if Hidden Singles are needed, Medium; if Naked Pairs are needed, Hard; if X-Wing is needed, Master.
Relationship to Number of Givens
The number of givens serves as a rough indicator of difficulty but is not decisive. Puzzles with the same number of givens can vary greatly in difficulty depending on placement patterns. Some puzzles with few givens can be solved through a chain of Naked Singles, while others with many givens may require X-Wing.