Puzzle generator
Sudoku Puzzle Generator
Generate a brand new, fully valid sudoku puzzle at the difficulty you choose, then download it as a clean PDF with the solution on page two. Every puzzle is unique and solvable with logic alone.
This is the PrintNook page, not the printable sheet.
To print the sheet at its true size, go back and use the Print or Download PDF button, then print at 100 percent scale, not Fit to page.
Free for personal and commercial use, solutions included. Print at 100 percent scale, not Fit to page.
A fresh puzzle whenever you want one
Sudoku asks you to fill a nine by nine grid so that every row, column, and three by three box contains the digits one to nine exactly once. Instead of buying a book, generate exactly the puzzle you want. Press New puzzle for another grid, switch difficulty for more or fewer starting clues, and print a stack for the week.
How to use it
- Choose a difficulty. Easy, medium, hard or expert. Harder levels leave fewer starting clues.
- Generate a puzzle. Press New puzzle for a freshly built grid. Repeat until you get one you like the look of.
- Pick the page size. A4 or Letter, so the grid is drawn for the sheet in your printer rather than scaled to it.
- Download and print. Press Download PDF. The puzzle prints on page one and the solution on page two.
Difficulty levels
- Easy reveals plenty of clues, ideal for beginners and quick solves.
- Medium asks for a little scanning and elimination.
- Hard hides more numbers and rewards patient deduction.
- Expert leaves the fewest clues for a serious challenge.
The answer key is included. Every download has the solutions printed after the puzzles, so you can check your work or hand out puzzles with an instant marking sheet.
Frequently asked questions
Is every puzzle solvable?
Yes. Each puzzle starts from a complete, valid solution grid and clues are removed only while the puzzle still has exactly one answer, so it can always be finished by logic without guessing.
How do the four difficulty levels differ?
They differ in how many clues are left on the board. Easy leaves the most numbers showing, and each step up to medium, hard and expert removes more, which lengthens the chain of deductions you need.
Where is the solution?
On the second page of the PDF. That keeps the puzzle page clean to work on and gives you an answer key you can check against or hand out separately.
Can I print a whole stack of different puzzles?
Yes. Set the Puzzles control before downloading and the PDF holds that many different grids with all the solutions collected at the back.
Does the same puzzle come back if I reload?
No. Every press of New puzzle builds a fresh grid in your browser, so the odds of repeating one are effectively nil and nothing is stored between visits.
Can I use these puzzles in a classroom or a newsletter?
Yes. The generated PDFs are free for personal, classroom and commercial use, with no attribution required and no watermark.
Related printables
Looking for ready-made sheets? The free printable sudoku page has presets and a full guide. Doing a puzzle a day? Tick it off on a printable habit tracker, or plan a puzzle club on a monthly calendar. Designing logic puzzles of your own? Graph paper takes any square size from 2 to 20 mm.