Kakuro looks like a crossword but uses sums. White runs have a clue; digits 1–9 fill the run, cannot repeat within that run, and must add to the clue.
Black cells separate runs — horizontal and vertical clues intersect like a crossword.
How to play Kakuro
- Each white run has a sum clue (shown at the start of the run).
- Digits 1–9 fill white cells. No digit repeats within a single run.
- Digits in a run must add exactly to the clue sum.
- Crossing runs share cells — a digit must satisfy both its horizontal and vertical run.
Strategy tips
- Learn unique combinations for short runs (e.g. sum 17 in two cells must be 8+9).
- Fill runs that cross the most other runs first — they constrain the grid fastest.
- A run of length N with sum S has limited possibilities; eliminate combos that need a digit already used in the crossing run.
- Long runs with high sums leave fewer combinations — check reference tables mentally for 6-cell runs.
- If kakuro feels dense, warm up on Mini Sudoku or Killer Sudoku for digit-placement practice.
Common questions
Is Kakuro like Killer Sudoku?
Both use sums without repeating digits in a group, but kakuro is run-based like a crossword while killer uses sudoku boxes plus cages.
