Diagonal Sudoku
Diagonal Sudoku, also known as Sudoku X, adds the two main diagonals to the classic rules.
Diagonal Sudoku
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Keyboard: 1–9 enter · arrows move · N notes · Backspace clear · Ctrl+Z undo
How to Play Diagonal Sudoku
- Follow the standard row, column and 3×3 box rules.
- Both main diagonals must also contain the digits 1 to 9 exactly once.
- The centre cell belongs to both diagonals and must satisfy both.
Tips for Solving
- Check diagonal restrictions as well as the usual row, column and box.
- Give special attention to the centre cell, which connects both diagonals.
- Look for a digit that has only one possible position along a diagonal.
Frequently Asked Questions
Is Diagonal Sudoku free to play?
Yes. Every Diagonal Sudoku puzzle on Sudoku Shrine is free in your browser, with no account or download.
Does every Diagonal Sudoku puzzle have one solution?
Yes. Each puzzle is checked by a solver so it has exactly one solution and can be solved by logic alone.
Which difficulty should I start with?
Start with Easy to learn the layout, then move to Medium and Hard once scanning and notes feel natural.
Is my progress saved?
Yes. Your entries and notes are saved in this browser, so you can close the page and continue later.