9
8
3
3
7
3
8
9
4
7
5
6
4
1
1
9
4
7
2
6
7
8
2
5
6
2
9
Time 00:00
Mistakes 0
Ready
Hard Sudoku #21
Advanced patterns: X-Wings, triples and tighter candidate logic.
| Difficulty | Hard |
| Clues given | 27 of 81 |
| Technique score | 131.2 |
| Rated techniques | 7 |
Techniques this puzzle needs
Where to start
The first move on this board is a Hidden Single: In this row 4, 4 can only go in one cell, so it must go there.
Progress is saved in this browser automatically. Use the keyboard: arrows to move, 1–9 to fill, N for notes, H for a hint.