How to Play Sum Grid
Sum Grid is a quick arithmetic puzzle: the numbers are all there, and your job is to decide which ones to throw away.
The rules
- Each row has a target on its right and each column a target below it.
- Cross out numbers so that the numbers left in every row and every column add up exactly to its target.
- Every puzzle has exactly one answer.
Playing on kawu
Tap a number to cross it out, tap again to mark it kept with a ring, and a third time to clear. A target turns green when its line is complete and correct, and red when the kept numbers overshoot it or the remaining numbers can no longer reach it. Sizes 4×4, 5×5 and 6×6; the daily puzzle is 5×5 and timed. Hint fixes a wrong mark first, then decides the cell in the most constrained line.
Next: Sum Grid solving tips.
Frequently asked questions
Do I have to cross out at least one number in every line?
In practice yes: puzzles are made so that every row and column keeps at least one number and loses at least one. Nothing in the rules stops a full or empty line, but the targets never ask for one.
Why mark numbers as kept?
Marking a number kept records a decision and lets the target beside the line turn green when the line is finished. You can solve a puzzle by crossing out alone; the ring is there to help you keep track.
Last updated 2026-10-21