About 12×12 Hard Sudoku
A 12×12 Sudoku uses numbers 1–12 and twelve 3×4 boxes. Significantly harder than 9×9.
At Hard difficulty, 30% of the 144 cells are pre-filled, leaving 100 cells for you to solve. Requires careful technique and pencil marks.
Tip: Use the Notes feature to pencil in candidates for each empty cell before committing.
Other difficulty levels for 12×12
Questions
How many hard 12×12 Sudoku puzzles are available?
Unlimited. Every time you click "New Game" a brand-new algorithmically generated puzzle is created. You will never run out of puzzles.
Are these puzzles printable?
Yes! Visit our printable Sudoku page to generate 4 puzzles per page as a PDF. Free, no login needed.
What solving techniques does Hard difficulty require?
Naked/hidden pairs, pointing pairs, and advanced elimination.
Play Hard 12×12 Sudoku now
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