4
7
6
4
2
3
1
7
1
5
8
9
2
9
8
6
2
4
1
4
8
5
2
6
8
Time 00:00
Mistakes 0
Ready
Hard Sudoku #178
Advanced patterns: X-Wings, triples and tighter candidate logic.
| Difficulty | Hard |
| Clues given | 25 of 81 |
| Technique score | 105.4 |
| Rated techniques | 4 |
Techniques this puzzle needs
Where to start
The first move on this board is a Naked Single: Row 3, column 5 already sees all eight other digits in its row, column and box, so it can only be 8.
Progress is saved in this browser automatically. Use the keyboard: arrows to move, 1–9 to fill, N for notes, H for a hint.