Kakuro (Cross Sums) Puzzle
Fill every run with different digits from 1 to 9 that add up to its clue. Pick a size, tap a white cell, enter digits with the keypad or your keyboard, and press Check whenever you like.
Select a white cell, then tap a digit.
How to play Kakuro
Select and type
Tap a white cell, then tap a digit from 1 to 9 on the keypad or type it. Erase, Backspace or 0 clears the cell.
Hit every sum
A run is a line of white cells. Its digits add up to the clue on the shaded cell just left of it (across) or just above it (down).
No repeats
A digit can appear only once in each run. Turn on Notes to pencil in the digits that could still fit.
Kakuro is a number puzzle laid out like a crossword. It is also called Cross Sums. Instead of letters you write digits from 1 to 9, and instead of word clues you get sums. Each run of white cells has to add up to its clue, and a run never uses the same digit twice. A fair Kakuro has one finished grid, and every puzzle here does.
Rules
The grid has shaded clue cells and white cells. Every white cell takes one digit from 1 to 9. No digits are given at the start.
A run is an unbroken line of white cells, across or down. Every run is at least two cells long.
Each run has a clue. A clue cell is split by a diagonal: the number in the upper right is the sum for the run to its right, and the number in the lower left is the sum for the run below it.
The digits in a run add up to its clue, and no digit appears twice in the same run. A digit may repeat elsewhere in the grid, as long as it is in a different run.
Each puzzle here has one solution.
Controls
Tap a white cell to select it. Its across and down runs are tinted, and their clues turn yellow. Tap a digit on the keypad under the board, or type 1 to 9. Erase, Backspace, Delete or 0 clears the cell. The arrow keys jump to the next white cell, skipping clue cells.
Notes are small pencil marks for the digits a cell could still be. Turn on Notes with the button or the N key, then each digit you tap or type switches that mark on or off. Shift with a digit adds or removes a note without turning Notes on. A cell shows either its digit or its notes.
A repeated digit in a run, a run whose digits already add up to more than its clue, and a full run with the wrong total are marked red as soon as they appear. The line under the keypad shows the selected cell’s clues and how much each run still needs. Press Hint for a digit the rules already force, with the idea behind it. Press Check when you want the board scored against the rules. Undo and Redo step through your moves, and Reset clears the grid.
Beginner tips
Start with sums that can be made only one way. In two cells, 3 is 1 and 2, 4 is 1 and 3, 16 is 7 and 9, and 17 is 8 and 9. In three cells, 6 is 1, 2 and 3, and 24 is 7, 8 and 9. Where two such runs cross, the shared cell must hold a digit that both sets contain.
Small and large clues narrow things fast. A two-cell run that sums to 5 can only use 1 and 4 or 2 and 3, so it never holds a 5 or more. A two-cell run that sums to 15 uses 6 and 9 or 7 and 8.
When a run has one empty cell left, subtract the digits you have placed from the clue. That difference is the missing digit. Easy grids fall to these ideas. Harder grids need you to list the digit sets that still fit a run and cross them off against the run going the other way.