🥷 Number Ninja
Slice the falling number that solves the equation before it hits the ground.
How to play
- Solve the equation shown at the top, like "x + 3 = 8" means x is 5.
- Tap or click the falling number that matches the answer to slice it.
- Or type the answer on your keyboard and press Enter to slice it from anywhere.
- Slicing the wrong number, or letting the right one hit the ground, costs a heart.
- Solve a few and a brand new equation appears. Pick Easy, Medium, or Hard to change the math.
Math practice that plays like an arcade game
Number Ninja turns basic algebra into a fast-paced falling-object game: an equation like "x + 3 = 8" sits at the top of the screen, numbers drift down from above, and you slice whichever one currently equals the answer, either by tapping it directly or typing the answer and hitting Enter from anywhere on screen. A number's correctness is judged against whichever equation is active right now, not the one that was active when it spawned, so an equation changing mid-fall never feels unfair.
Three difficulty tiers change the actual math involved: Easy covers one-step addition and subtraction, Medium brings in multiplication and division, and Hard uses two-step equations like "2x - 8 = 6". Three hearts give room for a couple of mistakes, whether that's slicing the wrong number or letting a correct one reach the ground unsliced, and your best streak for each difficulty is tracked locally. Want a slower, more deliberate kind of math puzzle instead of a timed one? Try Number Forge.
Free, no download, no account. See more math and logic games on the Math Games page, or more quick-round games on the Arcade Games page.
Frequently asked questions
How do I know which number to slice?
An equation is shown at the top, like "x + 3 = 8", meaning x is 5. Slice whichever falling number currently equals the answer, either by tapping it or by typing the answer and pressing Enter from anywhere on screen.
What math does Number Ninja cover?
Three difficulty tiers: Easy is one-step addition and subtraction, Medium adds multiplication and division, and Hard uses two-step equations.
What costs a heart?
Slicing the wrong number, or letting the correct number reach the ground without slicing it, each cost one of three hearts.
Does the equation change?
Yes, a fresh equation appears after every few correct slices, keeping the math varied within your chosen difficulty.