Free Printable Sudoku Generator

Print a fresh sudoku in seconds — classic 9×9, or kid-friendly 4×4 and 6×6 grids — in four honest difficulty grades. Every single puzzle is mathematically verified to have exactly one solution, and the answer key comes with the PDF.

Difficulty that means something

• Easy — solvable with singles alone; a relaxed coffee-break grid.
• Medium — a comfortable step up for everyday solvers.
• Hard & Expert — fewer givens, real techniques required.
• 4×4 and 6×6 kids grids — the classic rules at a size young solvers can finish.

Many free sudoku sites print puzzles with multiple solutions or mislabelled difficulty. PuzzleBindery generates each grid, then digs clues while re-verifying uniqueness at every step — the same engine used for published puzzle books.

Need 200 sudoku, not one?

The PuzzleBindery Book Studio batch-generates whole graded collections — for example 200 puzzles from Easy to Expert, four per page, with a compact solutions section — and exports a print-ready interior PDF for Amazon KDP. It's a one-time purchase, not another subscription.

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