About Number Sums: Mental Math Puzzle with Rows, Columns, and Regions

Number Sums is a challenging number puzzle built to train mental arithmetic. The goal is straightforward to state but demanding to execute: the sum of numbers in every row, every column, and every colored region must simultaneously equal the clue values shown on the sides of the board and inside each region. Every level has exactly one solution, and finding it requires holding all three constraints — rows, columns, and colored regions — in mind at once. The game offers math puzzles across various difficulty levels, making it suitable for anyone looking to sharpen addition skills and logical thinking.

How to Play Number Sums

Each board presents a grid of numbers alongside clue values on the sides and inside the colored regions. The task is to identify which numbers belong and which are surplus, so that every row, column, and colored region sums to its assigned clue simultaneously. Because each level has only one valid solution, rows, columns, and regions must all be satisfied at the same time — solving one in isolation is not enough.

Board Sizes and Difficulty

• Boards range from 3×3 up to 10×10, with difficulty increasing across that range.

Core Actions

• Circle the numbers that add up to the clue values for their row, column, and colored region.
• Use the toggle to switch between circling mode and erasing mode, marking correct numbers and removing the ones that are not needed.
• Ensure that all rows, columns, and colored regions work together correctly before considering a level complete.

Games You Might Like

If number logic keeps you engaged, Math Crosswords layers addition, subtraction, multiplication, and division into crossing equations — every shared cell must satisfy two equations at once, much like Number Sums demands every cell satisfy its row, column, and region. Sudoku shares the same single-solution discipline, filling a 9×9 grid so each digit appears exactly once in every row, column, and 3×3 square. For pure spatial logic without arithmetic, Arrows challenges you to clear a field of directional arrows within a limited number of moves, requiring careful planning at every step. Word-puzzle fans who enjoy grid-based deduction will find Crossword: Arrowword Puzzles a satisfying companion, with 100 arrowword levels that reward methodical thinking.

Browse the full Educational games collection for more skill-building titles, or explore the wider Puzzle games and Number games categories for additional challenges in the same vein.