Just Sum! Number Logic Puzzle

Pick the numbers to keep. Land every sum exactly.

Just Sum! is a calm number puzzle built on one simple idea: every row, every column and every colored area has a target sum. Tap the numbers you want to KEEP, leave the rest behind, and the moment all your sums match, the level is solved.

You never have to guess. Every board is generated the moment you start it and verified by a solver, so there is exactly one solution — and pure logic will always get you there.

HIDDEN ? CELLS
From level 31, some tiles hide their number behind a "?". You still have to decide whether to keep them, using only the sums around them. Get it right and the number is revealed. It is the twist that keeps the bigger boards interesting.

FEATURES
• Endless levels that grow from a cozy 3x3 up to a demanding 10x10
• Every board freshly generated with a guaranteed unique solution
• Hidden ? cells unlock as you progress — from one per board up to six
• No timer, no lives, no game over. Mistakes are counted, never punished
• Stuck? Trade a rewarded ad for a hint that solves one cell for you
• Stats kept on your device: highest level, clears, flawless clears, best time per board size, total play time
• 7 achievements to chase, from reaching level 10 to 100 total clears
• Warm rounded visuals, with a dark mode that is genuinely bright and easy on the eyes
• Rich haptic feedback on every tap, every mistake and every completed line
• Boards are generated on your device, so you can keep playing offline
• iPhone and iPad, in English, Japanese, Korean, Spanish, Simplified and Traditional Chinese

HOW TO PLAY
1. Tap a number to keep it. Tap it again to undo
2. Match the target sum on every row, every column and every colored area
3. The numbers you never tap are the ones you erase
4. When all the sums line up, the level is clear

Thirty seconds or thirty minutes — pick up where you left off, and make it add up.

Free to play, supported by ads.