Printable puzzles

Sudoku Generator & Printable PDF Maker

Generate sudoku puzzles with exactly one solution – easy, medium, hard or a mixed progression – and download a print-ready PDF with an answer key.

One solution, verifiedLarge print optionPrint-ready PDF

Last updated: October 2026

Preparing puzzles…

Solving on paper

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Printing your own puzzles? A few things make paper solving more comfortable.

Large print sudoku booksPrefer a printed book? Large-print editions are easier on the eyes and make easy gifts.See options on Amazon →Mechanical pencils with erasersSudoku is a pencil game – erasers make trial and error painless.See options on Amazon →Lap desk or clipboardA firm surface for solving on the couch or in bed.See options on Amazon →

What does this sudoku generator do?

It creates classic 9 × 9 sudoku puzzles and checks that each one has exactly one solution, then lays them out as a printable PDF with an optional answer key. Teachers, puzzle fans and self-publishers can make worksheets, gift booklets or book interiors without installing anything.

How to make a printable sudoku PDF

  1. Choose a difficulty (Easy, Medium, Hard or Mixed) and how many puzzles you want, from 1 to 300.
  2. Pick the page size and how many puzzles to print per page – 1 per page gives a large-print layout.
  3. Click Generate puzzles and check the preview.
  4. Click Download PDF to get a print-ready file with page numbers and an answer key.

Privacy, formats, and limits

  • Upload: Nothing is uploaded; puzzles and the PDF are created in your browser.
  • Output: A PDF in Letter, 6 × 9 in or A4, with page numbers.
  • Limit: Up to 300 puzzles per PDF. Large sets can take a few seconds on phones.
  • Difficulty: Graded by clue count and the solving techniques needed – a guide, not an official rating.

Example

120 Mixed puzzles at 1 per page on Letter paper give a 141-page PDF: a How to play page, 120 large-print puzzles moving from easy to hard, and 20 answer-key pages with 6 solutions each.

Frequently asked questions

Does every puzzle have exactly one solution?

Yes. Each puzzle is checked by a solver that counts solutions. If removing a number would allow a second solution, that number is put back, so every puzzle you get has exactly one answer.

How is the difficulty decided?

Easy puzzles have about 38 clues and Medium about 32; both can be solved with basic techniques (naked and hidden singles), and Medium needs hidden singles. Hard puzzles have about 24–30 clues and may need more advanced techniques. Mixed gives you a progression from easy to hard.

Can I use the puzzles in a book I sell?

Yes. You can use the puzzles you generate for any purpose, including printed puzzle books such as Amazon KDP interiors. Always check the final PDF against your printer's or KDP's current requirements before publishing.

What do the seed and volume fields do?

The same seed, volume and difficulty recreate exactly the same puzzles, so you can rebuild a PDF later. Change the volume number to get a completely new set of puzzles for the next book in a series.

Is the PDF ready for print-on-demand?

The page size matches the trim you choose (Letter 8.5 × 11 in, 6 × 9 in or A4), there is no bleed, and margins are 0.75 in on every side, which is wider than KDP's minimum no-bleed margins for most page counts. Check it in KDP's previewer before you publish.