Sum Logic Puzzle: Keepsum

Keepsum is a logic puzzle about sums. Every number on the board is either kept or erased. Keep the right ones so that every row and column adds up to its clue.

Circle the numbers to keep and erase the rest. A line that adds up gets a check, and when the numbers you kept already make a clue, tap it to erase the rest of the line at once. Every puzzle has exactly one answer, and you can always reach it step by step. No guessing needed.

THREE WAYS TO PLAY
• Classic — No timer. Pick a board from 5×5 to 9×9 and solve puzzles to unlock bigger boards. Puzzles get a little harder as you go.
• Daily — One new 7×7 puzzle every day, the same for everyone. Keep your streak going and share your time.
• Rush — Start with 3 minutes and get 30 more seconds for every 5×5 puzzle you solve. How many can you solve?

HINTS THAT EXPLAIN WHY
Stuck? A hint first shows which line to look at, then the cell to decide and the reason: "Without 9, the other numbers can't reach the clue 31. Keep this 9." It also finds cells that don't match the answer, so you learn the logic instead of guessing.

NO LIVES, NO PRESSURE
• A mistake never ends a puzzle. Hints and undo are free and unlimited in Classic and Daily.
• Optional helpers: show current sums, erase the rest automatically, show mistakes, row and column guide, large numbers.
• Drag to mark a whole row or column in one stroke.

COMFORTABLE TO PLAY
• No sign-up, no login. Plays offline.
• Paper-and-pencil sounds, gentle animations and vibration. Turn off any effect you don't want, or reduce them all.
• One small banner ad at the bottom, removed while you play Rush.
• English, Korean, Japanese and Chinese (Simplified and Traditional).

Love logic puzzles, number puzzles and brain games? Keepsum is a calm puzzle for a few quiet minutes, or for as long as you like.