Kakuro Solver
Stuck on a Kakuro? Build the grid of your puzzle, enter the down and right sums from the clue cells, and press Solve. The solver fills every white cell, tells you if the puzzle has more than one answer, and points out sums that cannot be made with the number of cells available.
Tap a white cell to make it a clue cell, then type its sums: bottom-left for the run going down, top-right for the run going across.
Grid size
How to use the Kakuro solver
- Choose the grid size, counting the clue border (a 7×7 grid has a 6×6 playing area). By default the first row and first column are clue cells, as in most printed Kakuro.
- Tap a white cell to turn it into a clue cell. Tap the × in the corner of a clue cell to turn it back into a white cell. Copy the black cells from your puzzle.
- In each clue cell, type the sum for the run below it in the bottom-left box and the sum for the run to its right in the top-right box. Leave a box empty when no run starts there.
- Press Solve. The solved digits appear in colour. Press Clear to start a new grid, or Load example to see how the tool works.
Kakuro solver FAQ
- How do Kakuro sum combinations work?
- Each run of white cells must add up to its clue, and no digit may repeat inside the run. That limits the choices a lot: a sum of 4 in two cells can only be 1 + 3, a sum of 16 in two cells can only be 7 + 9, and a sum of 6 in three cells can only be 1 + 2 + 3. The solver precomputes every set of distinct digits for every sum and length, then combines the sets of each across and down run to cut the options.
- Is this Kakuro solver free?
- Yes. It is completely free, needs no sign-up, and runs in your browser, so the puzzle you enter never leaves your device.
- What does 'more than one solution' mean?
- A proper Kakuro has exactly one answer. If you see this message, a clue sum was probably mistyped or a black cell is missing. The solver still shows you one valid way to fill the grid.
- Why does the solver say my sums are impossible?
- Every run has a smallest and a largest possible total. For example, two cells can only add up to between 3 and 17, and three cells between 6 and 24. If a clue is outside that range, or a run of white cells has no sum at all, the layout cannot be right, so check the highlighted cell against your puzzle.
- How big a Kakuro can it solve?
- Grids from 5×5 up to 12×12, including the clue border. Runs can be up to nine cells long, since each digit from 1 to 9 can be used only once in a run.