About SUM+SUM

Free to play and quick to load, SUM+SUM is a logic challenge that runs entirely in your web browser. The rules take seconds to learn, but the later levels will genuinely make you stop and think. Touch controls are supported, so you can pick it up on mobile without losing anything. Like everything on LemonArcade, it is unblocked — it works at school, at work and on Chromebooks.

How to play SUM+SUM

Study the board, plan a couple of moves ahead and clear each level in as few steps as possible. On mobile, the on-screen touch controls take over — tap to interact. Expect a gentle start and a real challenge soon after.

• Mouse Click to keep/delete

Tips to get better at SUM+SUM

• Mistakes are cheap: restarting a level early beats grinding a doomed position.
• Take a short break when a level resists you; fresh eyes solve puzzles faster.
• If you are stuck, look for the move that frees up the most space rather than the quickest win.