Medium Killer Sudoku Online

Medium Killer Sudoku is the sweet spot — cages average two to three cells, sums force enough constraint to make every move feel earned, and the puzzles solve in under twenty minutes with steady technique. You'll start each puzzle by listing cage-combination possibilities (a 3-cell cage summing to 7 can only be {1,2,4}; a 3-cell summing to 24 must be {7,8,9}; a 4-cell summing to 10 is {1,2,3,4}). From there, the 45 rule — every row, column, and box sums to 45 — lets you compute innies (cells protruding into a box from outside cages) and outies, which pin entire cages at once. Solving on Sudoku247 means freshly generated puzzles every play, uniquely solvable via pure logic, and a clean dashed-cage outline so you always know which cells share a sum.