Number Grid Puzzle
Every row and column is an arithmetic equation. Fill in the missing numbers (and at harder levels, the missing operations) so that each equation evaluates correctly from left to right. A math grid puzzle that works your arithmetic and logic at the same time.
Number Grid
3×3 grids. Addition and subtraction only. 2–3 missing numbers.
Standard play. Timer runs. Hints available.
What is a number grid puzzle?
A number grid puzzle is a square grid where every row and every column forms a complete arithmetic equation. Some cells come pre-filled, and you work out what goes in the blanks. A simple 3×3 might look like: 3 + ? = 7 across and 3 × ? = 9 down, sharing that top-left 3. The missing number has to satisfy both directions at once.
The format goes by a few names — math grid puzzle, arithmetic puzzle, or sometimes cross-number puzzle (though that term can also mean something different). What makes it distinctive is the left-to-right evaluation rule. There is no order of operations here. 2 + 3 × 4 evaluates as (2 + 3) × 4 = 20, not 2 + 12 = 14. This keeps the puzzles accessible for kids learning basic math while still creating interesting logic chains at higher levels.
Unlike a nonogram (sometimes also called a "number grid"), this puzzle involves actual arithmetic. And unlike a hundred chart used in early education, it is a proper puzzle with a unique solution that requires deduction to solve.
How to play online
Click or tap any blank cell. Square cells hold numbers — you will see a numpad appear at the bottom. Circular cells hold operations (+, −, ×, ÷) — tap to toggle between them, or press the corresponding key on a keyboard.
As you fill in values, the equals sign for each equation updates in real time. A green checkmark means that equation is correct. A red ✗ means something is off. When every equation shows green, the puzzle is solved.
You get up to three hints in Classic and Timed Trial modes. Each hint fills in one blank cell for you. Challenge mode disables hints and undo, so every placement is final.
Play modes
Classic
Timer runs. Up to 3 hints. Undo and redo available.
Timed Trial
Beat the clock. Bigger grids get more time.
Challenge
No hints, no undo. Every placement sticks.
Print worksheets
Need number grid worksheets for a classroom or homework? The printable page has clean layouts for all five difficulty levels. Each worksheet includes instructions at the top and an answer key. Easy and medium fit two puzzles per page; hard and above get a full page each.
How to solve number grid puzzles
Strategies that work across every grid size.
The core skill is cross-referencing. Each number cell appears in two equations (one horizontal, one vertical). When you know everything else in one of those equations, you can compute the missing value directly. Then plug it into the other equation and see what that tells you.
Start with single-blank equations
Look for rows or columns where only one cell is unknown. If the row reads 5 + ? = 8, the answer is 3. Fill it, then check the column that cell belongs to — it might now have only one blank left too. These freebies cascade into each other and can solve a large chunk of an easy puzzle without any real decision-making.
Remember: left to right only
This is the single most common mistake. 4 + 6 ÷ 2 is not 7. It is (4 + 6) ÷ 2 = 5. Every operation applies to the running total, reading from left to right. Once this clicks, the puzzles become much more predictable — you can compute intermediate totals as you scan along an equation.
Work backwards from the result
If a row reads ? × 3 = 12, work backwards: the unknown is12 ÷ 3 = 4. For longer equations, you can sometimes work inward from both ends. If you know the final result and the starting number, the operations and middle values are more constrained than they first appear.
Division must be exact
Every division in a number grid puzzle produces a whole number. If you are trying a value and the division gives you a fraction, that value is wrong. This is an easy way to eliminate possibilities on harder grids where several cells might seem equally valid.
On harder grids: narrow down operations first
At hard difficulty and above, some operation cells are blank too. Usually only one or two operations produce valid whole-number results with the surrounding numbers. Try each one mentally and cross off anything that leads to a fraction or an answer that conflicts with the crossing equation. This often pins the operation before you fill any number blanks.
Grid size progression
Easy (3×3) uses addition and subtraction with numbers under 10. The 6 equations are short and usually have just 2 or 3 blanks total. Medium stays at 3×3 but adds multiplication and division, raising the number range to 20. Hard bumps up to a 4×4 grid (8 equations) and introduces blank operations. Expert is 5×5 (10 equations, up to 10 blanks), and Einstein goes to 6×6 with negative numbers.
If easy feels instant, jump to medium. If you want the full challenge, go to expert or einstein.
Difficulty levels
Number Grid vs KenKen vs Kakuro
All three are arithmetic grid puzzles, but they play differently. KenKen gives you a Latin square with caged regions — each cage has a target and an operation, and no digit repeats in any row or column. Kakuro uses a crossword-shaped grid where you fill white cells so runs of cells sum to the clues, using each digit at most once per run.
Number Grid is more direct. There are no cages or run-sum clues. You see full equations — numbers, operations, equals signs — and you fill the gaps. This makes it the most accessible of the three, especially at easy difficulty where only addition and subtraction appear. It works well for younger students who are still learning their times tables, and for adults who want a quick arithmetic warm-up without the deeper logic of KenKen or Kakuro.
If you enjoy Number Grid and want something more involved, KenKen adds the no-repeat constraint and cage reasoning. Kakuro takes it further with flexible run lengths and sum-based deduction. They are a natural progression.
Resources
More puzzles
KenKen
Cage arithmetic meets Latin squares. No digit repeats in any row or column.
Kakuro
Cross-sum number puzzles. Fill runs of cells so they sum to the clue digits.
Killer Sudoku
Sudoku with cage sums. Digits in each cage add to a target.
Futoshiki
Latin squares with inequality constraints between cells.
Math Riddles
Word problems with step-by-step proofs.
Sudoku
The classic 9×9 number placement puzzle.