Fill each row, column, and 3x3 box with 1-9 without repeats, and the numbers in each dashed cage must sum to the indicated value.
How to Play
Tap an empty cell to select it
Enter a number using the keypad below
Switch to memo mode to note candidate numbers
Cage Sum Rule
The numbers in a dashed cage must add up to the target shown in the top-left corner
No Duplicates in Cage
The same number cannot be used twice within the same cage
Completed Example
Standard Sudoku rules: each row, column, and 3x3 box contains 1-9 exactly once.
Numbers in each dashed cage must add up to the target sum shown in the top-left corner.
No number can be repeated within the same cage.
Tip
Start with small cages (2-3 cells) first
Think about which number combinations can produce each sum
Use memo mode to note down candidate numbers
Killer Sudoku requires simultaneous arithmetic calculation and logical elimination, imposing high cognitive load on working memory and executive functions.
Crook (2009) - A Pencil-and-Paper Algorithm for Solving Sudoku Puzzles
Miyake et al. (2000) - Unity and Diversity of Executive Functions