Every Kakuro clue tells you the sum of a run of cells, each containing a unique digit from 1 to 9. Some clues have only one valid combination of digits — meaning both the values and their placement are forced. Others have many options, requiring cross-referencing with intersecting clues.
This page gives you the complete reference: every valid combination for 2-cell, 3-cell, 4-cell, and 5-cell runs, organized by sum.
These clue/length combinations have exactly one valid set of digits. Once you see them, the values are determined immediately. Only the arrangement within the run needs figuring out.
| Sum | Length | Only combination | Note |
|---|---|---|---|
| 3 | 2 cells | {1, 2} | Only way to sum 3 with 2 digits |
| 4 | 2 cells | {1, 3} | |
| 16 | 2 cells | {7, 9} | |
| 17 | 2 cells | {8, 9} | Maximum 2-cell sum |
| 6 | 3 cells | {1, 2, 3} | Minimum 3-cell sum |
| 7 | 3 cells | {1, 2, 4} | |
| 23 | 3 cells | {6, 8, 9} | |
| 24 | 3 cells | {7, 8, 9} | Maximum 3-cell sum |
| 10 | 4 cells | {1, 2, 3, 4} | Minimum 4-cell sum |
| 11 | 4 cells | {1, 2, 3, 5} | |
| 29 | 4 cells | {5, 7, 8, 9} | |
| 30 | 4 cells | {6, 7, 8, 9} | Maximum 4-cell sum |
| 15 | 5 cells | {1, 2, 3, 4, 5} | Minimum 5-cell sum |
| 35 | 5 cells | {5, 6, 7, 8, 9} | Maximum 5-cell sum |
Each entry shows every valid pair of digits for that sum. All digits must be different (1–9).
| Sum | Options | Valid combinations |
|---|---|---|
| 3 | 1 | {1,2} |
| 4 | 1 | {1,3} |
| 5 | 2 | {1,4} {2,3} |
| 6 | 2 | {1,5} {2,4} |
| 7 | 3 | {1,6} {2,5} {3,4} |
| 8 | 3 | {1,7} {2,6} {3,5} |
| 9 | 4 | {1,8} {2,7} {3,6} {4,5} |
| 10 | 4 | {1,9} {2,8} {3,7} {4,6} |
| 11 | 4 | {2,9} {3,8} {4,7} {5,6} |
| 12 | 3 | {3,9} {4,8} {5,7} |
| 13 | 3 | {4,9} {5,8} {6,7} |
| 14 | 2 | {5,9} {6,8} |
| 15 | 2 | {6,9} {7,8} |
| 16 | 1 | {7,9} |
| 17 | 1 | {8,9} |
| Sum | Options | Valid combinations |
|---|---|---|
| 6 | 1 | {1,2,3} |
| 7 | 1 | {1,2,4} |
| 8 | 2 | {1,2,5} {1,3,4} |
| 9 | 3 | {1,2,6} {1,3,5} {2,3,4} |
| 10 | 4 | {1,2,7} {1,3,6} {1,4,5} {2,3,5} |
| 11 | 5 | {1,2,8} {1,3,7} {1,4,6} {2,3,6} {2,4,5} |
| 12 | 7 | {1,2,9} {1,3,8} {1,4,7} {1,5,6} {2,3,7} {2,4,6} {3,4,5} |
| 13 | 7 | {1,3,9} {1,4,8} {1,5,7} {2,3,8} {2,4,7} {2,5,6} {3,4,6} |
| 14 | 8 | {1,4,9} {1,5,8} {1,6,7} {2,3,9} {2,4,8} {2,5,7} {3,4,7} {3,5,6} |
| 15 | 8 | {1,5,9} {1,6,8} {2,4,9} {2,5,8} {2,6,7} {3,4,8} {3,5,7} {4,5,6} |
| 16 | 8 | {1,6,9} {1,7,8} {2,5,9} {2,6,8} {3,4,9} {3,5,8} {3,6,7} {4,5,7} |
| 17 | 7 | {1,7,9} {2,6,9} {2,7,8} {3,5,9} {3,6,8} {4,5,8} {4,6,7} |
| 18 | 7 | {1,8,9} {2,7,9} {3,6,9} {3,7,8} {4,5,9} {4,6,8} {5,6,7} |
| 19 | 5 | {2,8,9} {3,7,9} {4,6,9} {4,7,8} {5,6,8} |
| 20 | 4 | {3,8,9} {4,7,9} {5,6,9} {5,7,8} |
| 21 | 3 | {4,8,9} {5,7,9} {6,7,8} |
| 22 | 2 | {5,8,9} {6,7,9} |
| 23 | 1 | {6,8,9} |
| 24 | 1 | {7,8,9} |