Hard Sudoku to print (free PDF)
Download free hard Sudoku puzzles to print as PDF, ready for A4 or US Letter. A serious workout for experienced solvers.
Sample puzzles
9
4
2
5
1
2
3
7
6
2
1
5
6
2
1
8
4
5
6
8
3
4
7
5
9
6
3
8
1
6
7
4
5
8
2
3
9
8
7
5
9
7
1
6
4
9
3
1
8
5
3
5
9
1
4
4
8
6
5
3
8
2
9
1
6
4
6
7
8
5
8
7
9
6
2
1
8
5
7
4
2
1
5
4
8
1
9
6
8
5
4
7
2
6
7
3
1
5
6
8
3
4
9
7
2
3
3
6
1
9
5
9
2
5
7
1
3
7
4
6
9
8
6
3
1
8
8
6
4
1
8
3
3
9
2
8
7
9
4
8
6
3
8
2
5
2
9
8
5
1
7
1
3
6
1
5
2
7
1
6
8
9
3
8
2
5
1
7
8
3
6
1
4
7
Why this level?
A hard Sudoku starts from about 26–28 clues, so scanning alone rarely cracks it. You'll rely on candidate notes and techniques like naked or hidden pairs to make progress.
How to print
Click "Download book", open the PDF and choose A4 or US Letter. Six puzzles per page; check yourself with the separate solutions PDF.
Solving tips
Fill in candidates fully, then hunt for pairs and triples that eliminate other candidates in the same row, column or box.
Frequently asked questions
What techniques do hard Sudoku need?
Beyond scanning, expect naked/hidden pairs and triples and pointing pairs — but not the most extreme chains.
How many starting clues do hard Sudoku have?
About 26–28, so scanning alone rarely cracks them — keep full candidate notes from the start.
How is hard different from very hard or evil?
Hard needs pairs, triples and pointing pairs; very hard and evil add the most extreme chains and far fewer clues.