Generate unlimited unique sudoku puzzles with answer keys. Download as PDF — free forever.
Every download looks like this — a full-page 9×9 grid formatted for US Letter paper. Set your difficulty below and generate your own.
Printing for a whole class? Generate a set where every student gets a different puzzle at the same difficulty — no two papers alike. One combined answer key for the whole set is included at the end of the PDF.
Using this across your whole school? See our School Site License — unlimited printing, campus-wide, $79/year.
Want a specific clue count locked in instead of setting it up yourself? Browse all sudoku difficulties — Easy, Medium, and Hard — each with its own printable page.
Our free sudoku generator creates unique puzzles using a backtracking algorithm — the same method used in professional puzzle books. Every puzzle is generated fresh in your browser, so no two downloads are the same. Puzzles are formatted for US Letter (8.5" × 11") paper with large, clear numbers perfect for printing. The answer key page uses red numbers to clearly distinguish filled-in answers from given clues. Ideal for elementary classrooms, after-school programs, senior centers, and homeschool families.