Free online Kakuro (cross sums) with no ads and no sign-up. Pick a 6×6, 8×8, 10×10 or 12×12 grid or play the daily puzzle, and every puzzle has exactly one solution. Pencil notes, hints, undo, run highlighting with the remaining sum, a mistakes counter, auto-save on phone and desktop so you can pick up where you left off, and leaderboards for puzzles solved and the fastest 10×10 times. Fill each run of white cells with digits 1 to 9 that add up to the clue in the black cell, without repeating a digit inside a run. The number above the diagonal is the sum of the run to its right, the number below it is the sum of the run beneath.