Sudoku
Printable 9 × 9 and 4 × 4 sudoku puzzles, each with exactly one solution and a technique-based difficulty.
Customize
Easy: singles only. Medium: needs pairs or locked candidates. Hard: needs triples, X-Wing or XY-Wing.
Same settings, new puzzles.
Made in your browser. Nothing you enter is uploaded.
Good to know
Does every puzzle have exactly one solution?
Yes. Clues are only removed while a separate solver still finds exactly one solution, and every finished puzzle is checked again before it is shown.
How is the difficulty decided?
A second solver works like a person, using only logical techniques, and records the hardest one it needs. Easy puzzles need only singles, Medium puzzles need pairs or locked candidates, and Hard puzzles need a triple, X-Wing or XY-Wing. A puzzle is only used if its rating matches the level you chose; none require guessing.