Volume Calculator
Find the volume of a box, cube, sphere, cylinder, or cone. Shows the formula and the steps.
Volume Calculator
π (pi) tells you how many times a circle's width (its diameter) wraps around the edge. It is the same for every circle, big or small - about 3.14159…
Its digits go on forever and never repeat, so no fraction is exactly equal to π. These are common stand-ins you can pick from:
- 22/7 - the classic school value. With a radius that is a multiple of 7, the answers come out as whole numbers.
- 3.14 - π rounded to two decimal places.
- π (3.14159…) - the most exact, for careful work. (Even this is rounded - the real π never ends.)
Choose the one your class or textbook tells you to use, so your answer matches theirs.
What Volume Means
Volume is how much space a solid takes up - picture how many unit cubes it would take to fill it. For a box you stack cubes in rows, in layers, so the volume is simply .
The round shapes follow the same “base times height” idea:
- A cylinder is a circle pushed straight up, so its volume is the circle’s area times the height ().
- A cone with the same base and height holds exactly one third as much as that cylinder - a handy fact to remember.
- A sphere works out to .
Pick a shape above and the diagram redraws to your measurements. For the round shapes you can also choose which value of π to use.
Volume Formulas
A cone holds exactly one third of the cylinder with the same base and height.
How to Use It
- Choose the shape.
- Enter the measurements it asks for.
- Read the volume and the steps.
Worked Examples
| Shape | Measurements | Volume |
|---|---|---|
| Box | 4 × 3 × 2 | 24 |
| Cube | side 4 | 64 |
| Sphere | radius 3 | ≈ 113.1 |
| Cylinder | radius 3, height 4 | ≈ 113.1 |
| Cone | radius 3, height 4 | ≈ 37.7 |
FAQ
How do you find the volume of a box?
Multiply length by width by height. For 4 × 3 × 2: .
What is the volume of a sphere?
Use . For a radius of 3: .
How do you find the volume of a cylinder?
Multiply the base area by the height: .
Why is a cone’s volume a third of a cylinder’s?
A cone with the same base and height holds exactly one third as much, so its formula is .