Statistics
Difficulty
Clues are the pre-filled numbers you can't change. You have 3 errors max; wrong entries turn red and count against the limit.
Number Selector
Sudoku Origins & Algorithms
🔧 Technical Trivia:
Game is based on "Backtracking with Constraint Propagation" and "Most Constrained Variable (MCV) Heuristic" Algorithms
📚 General Trivia:
"Sudoku" (数独) is a shortened version of the Japanese phrase "Sūji wa dokushin ni kagiru," which translates to "the digits must be single" or "the numbers are limited to one occurrence". Before it was called Sudoku, the puzzle was known as "Number Place". Despite its Japanese name, Sudoku was invented in the United States. It was created by an American architect named Howard Garns and was first published in 1979 in Dell Pencil Puzzles and Word Games magazine.
More Sudoku Facts & Tips
🎯 Strategy Trivia:
The key to solving Sudoku is "logical deduction", not guessing! Professional solvers use techniques like "Naked Singles" (cells with only one possible number), "Hidden Singles" (numbers that can only go in one cell within a row/column/box), and advanced strategies like "X-Wing" and "Swordfish" patterns. The world record for solving a Sudoku puzzle is under 1 minute and 23 seconds!
🌟 Fun Trivia:
There are exactly 6,670,903,752,021,072,936,960 possible completed Sudoku grids! However, when you account for rotations, reflections, and relabeling of digits, there are 5,472,730,538 essentially different solutions. The minimum number of clues needed for a valid Sudoku puzzle is 17 - no valid puzzle has been found with fewer clues. Sudoku is NP-complete, meaning it's computationally challenging to solve algorithmically as the grid size increases!
🧘 Wellness Trivia:
Playing Sudoku regularly can help improve memory, concentration, and logical thinking skills. Studies suggest that puzzle-solving activities like Sudoku may help delay cognitive decline and keep the mind sharp as we age. It's also a great stress-reliever and can provide a meditative, focused experience that helps clear mental clutter. The satisfaction of completing a challenging puzzle releases dopamine, creating a natural reward cycle!