Free Kakuro tool

Kakuro Solver Online

Build a Kakuro grid, add diagonal clue cells, enter any numbers you already know, and solve the cross sums puzzle in your browser.

Cell mode
Grid 5 x 5
Clues 0
Status Ready

Grid ready.

What is a Kakuro solver?

A Kakuro solver is a tool that fills a cross sums puzzle by applying the normal Kakuro rules. Each number cell must use a digit from 1 to 9, each clue run must add to its total, and no digit can repeat inside a single run.

This solver is designed for custom grids. You choose the size, mark black cells, add diagonal clue cells and enter any numbers already solved. The tool then calculates a completed grid if the clues are valid.

  • Solve a Kakuro puzzle from a newspaper, book or printable sheet.
  • Check whether your entered digits are still consistent.
  • Test a Kakuro grid you are creating.
  • Find out whether the clues have more than one answer.

How to use this Kakuro solver

Start by choosing the grid width and height, then create the board. Use the cell mode buttons to mark each square as a block, a clue cell or a number cell. Clue cells use the same diagonal layout as a printed Kakuro puzzle.

For each clue cell, enter the across total for the run to the right and the down total for the run below. If a clue only points one way, leave the other box blank. Number cells can be left empty or filled with digits you have already worked out.

  • Create the grid.
  • Paint the board with block, clue and number cells.
  • Type clue totals into the diagonal clue cells.
  • Enter any known digits in number cells.
  • Press Solve to reveal the completed grid.

Kakuro combinations and clue runs

Kakuro combinations are the sets of digits that can make a clue total without repeats. A 4-cell clue of 10 can only use 1, 2, 3 and 4, although the crossing clues decide the final order.

The solver uses those combinations internally. For every clue, it creates the legal digit orders, removes any order that clashes with known numbers, then compares intersecting across and down runs.

  • Run length controls how many digits are used.
  • The clue total controls which digit sets are possible.
  • Digits cannot repeat inside one run.
  • The same cell must satisfy both its across and down clue.

Why a Kakuro can be impossible or ambiguous

A Kakuro grid is impossible if a clue total cannot be made with the number of cells in its run, or if an entered digit breaks a clue total. A run of ten cells is also invalid in standard Kakuro because only digits 1 to 9 are available.

A grid can also be ambiguous. That means more than one set of digits satisfies the same clues. Published Kakuro puzzles normally have one unique solution so that every step can be reached by logic.

Kakuro solver article keywords

This page targets the practical search intent behind Kakuro solver, Kakuro puzzle solver and cross sums solver. The combinations topic still belongs here, but mainly as supporting guidance for solvers who want to understand why a clue is forced.

A separate Kakuro combinations chart can work better as an article because people searching for combinations often want a quick reference table rather than a full grid editor.

FAQ

Kakuro solver FAQ

Can this solve any Kakuro grid?

It can solve standard Kakuro grids that use digits 1 to 9, non-repeating digits inside each clue run, and across or down clue totals from 1 to 45.

What should a blank black square be?

Use Block for a plain black square. Use Clue when the square contains an across total, a down total or both.

Can I enter numbers I already solved?

Yes. Put them in number cells before pressing Solve or Check. The solver will keep them if they fit the clues.

Why does the solver say multiple solutions?

The clues do not force a single answer. The shown grid is valid, but another completed grid also satisfies the same clues.

Does this replace a Kakuro combinations chart?

No. The solver uses combinations, but a chart is better as a quick reference article for individual clue totals.