4
5
1
2
9
7
6
5
6
7
7
9
3
1
5
2
9
8
8
2
1
5
6
4
Time 00:00
Mistakes 0
Ready
Hard Sudoku #52
Advanced patterns: X-Wings, triples and tighter candidate logic.
| Difficulty | Hard |
| Clues given | 24 of 81 |
| Technique score | 108.9 |
| Rated techniques | 4 |
Techniques this puzzle needs
Where to start
The first move on this board is a Naked Single: Row 2, column 1 already sees all eight other digits in its row, column and box, so it can only be 3.
Progress is saved in this browser automatically. Use the keyboard: arrows to move, 1–9 to fill, N for notes, H for a hint.