Free Sudoku Puzzle Generator
Pick a difficulty and generate a printable sudoku puzzle with a guaranteed unique solution, plus an optional solution sheet. Everything runs in your browser — no sign-up, no app.
Tips for solving sudoku faster
Scan for forced cells first
Before guessing, look for rows, columns, or boxes where only one empty cell remains for a given number — these are free placements with no deduction needed.
Work box by box on Hard and Expert
With fewer starting clues, scanning the whole grid gets overwhelming. Pick one 3x3 box and figure out which numbers are missing and which cells they could go in before moving to the next box.
Pencil in candidates on hard puzzles
For Hard and Expert difficulty, lightly write every possible number in each empty cell's corner. Cells that narrow down to one candidate become your next placement.
Start on Easy or Medium if you're new
Easy and Medium puzzles leave enough clues that simple scanning solves most of the grid, which is the best way to learn the technique before tackling Hard or Expert.
Frequently asked questions
- Does every puzzle have exactly one solution?
- Yes. Each puzzle is checked as it's generated to make sure it has exactly one valid solution, the same guarantee as a published sudoku book.
- What's the difference between the difficulty levels?
- Difficulty is controlled by how many starting clues are left on the grid — Easy leaves around 38 clues, Medium around 30, Hard around 24, and Expert around 20. Fewer clues means more deduction is required to solve it.
- Can I print the solution too?
- Yes. Check "Include solution page" and a second, fully solved grid prints after the puzzle.
- Is this sudoku generator free?
- Yes, completely free with no sign-up. Free puzzles include a small footer credit; a one-time purchase can remove it.
- What's a good sudoku strategy for beginners?
- Start by scanning rows, columns, and 3x3 boxes for numbers that only have one possible cell left. Once the easy placements are used up, look for cells where only one number could possibly fit, working box by box.
- How long does a sudoku puzzle usually take to solve?
- It varies a lot by difficulty and experience — an Easy puzzle might take 5-10 minutes, while an Expert puzzle can take 30 minutes or more even for a practiced solver.