Sudoku Generator
Generate a unique-solution sudoku puzzle at four difficulty levels, then export it as a printable PDF with a full answer key.
Grid size
Difficulty
Generating puzzle...
About the Sudoku Generator
A sudoku generator creates a fresh puzzle with a guaranteed unique solution, in grid sizes from 4x4 up to 16x16 and four difficulty levels, then lets you export it as a printable PDF with a full answer key.
How to use
1
Choose a grid size, from a quick 4x4 puzzle up to a full 16x16 challenge.
2
Choose a difficulty level, then solve the puzzle on screen or click show solution if you get stuck.
3
Download the puzzle as a PDF, which includes a second page with the completed answer key.
Frequently asked questions
How do larger grids like 16x16 represent numbers above 9?
They use the letters A through G for the values 10 through 16, the standard convention for sudoku variants larger than the classic 9x9 grid.
Is every generated puzzle guaranteed to have only one solution?
Yes for every grid size, cells are only removed if doing so still leaves exactly one valid solution, which is checked automatically during generation.
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