Math Insight

The minimum number of clues (17) needed for a unique Sudoku was proved by exhaustive computer search in 2012.

Math Insight
✓ Completed! 👍
6
3
2
9
6
1
3
8
5
6
5
7
3
8
7
3
4
1
2
5
4
3
7
9
5
Pro Tip

Before using pencil marks, see how far you can get on a hard puzzle with pure mental tracking.

Pro Tip