Volume Calculator
Calculate the volume of a sphere, cylinder, cube or cone. Pick a shape, enter the measurements, and get the volume in cubic units and liters.
How to use the volume calculator
- Choose the shape you want to calculate the volume of, using the buttons above the calculator.
- Enter the measurements — the calculator works out the volume automatically as you type.
- See the volume both in cubic units and in liters.
How the volume is calculated
Each shape has its own volume formula:
Cylinder: V = π × r² × h
Cube: V = s³
Cone: V = (1∕3) × π × r² × h
Worked example: a sphere of radius 5 has a volume of (4 ÷ 3) × π × 5³ = 523.60 cubic units. Note that the radius is cubed: double it to 10 and the volume becomes (4 ÷ 3) × π × 1000 = 4,188.79, eight times as large rather than twice. That is why a ball of double the radius holds eight times as much air, and why volume grows so much faster than the measurements suggest.
Sphere and cone include π because they're built on a circular cross-section — π ties the radius to the area of that cross-section, just like with circle area.
Where volume conversion most often goes wrong
Volume scales with the cube of length, and that is the source of nearly every conversion error. Going from centimetres to metres, you divide the length by a hundred — but the volume by a million. A cubic metre is a thousand litres, a litre is a thousand cubic centimetres, and a cubic centimetre is exactly one millilitre. If an answer comes out a thousand or a million times too large or too small, the mistake is almost always here.
The same power rule explains why small changes in dimensions produce large effects. Increase every side of a container by ten percent and the volume grows by just over thirty percent. That is worth keeping in mind when judging whether a tank, a pool or a container is «a bit bigger» than another — the difference in contents is usually much larger than the difference in dimensions.
Frequently asked questions
Why do sphere and cone formulas include π?
Because both shapes are based on a circular form (the sphere's cross-section and the cone's base), and π is the ratio between a circle's circumference and diameter. It therefore shows up wherever circles and spheres are calculated.
How do I convert from cubic meters to liters?
1 cubic meter (m³) equals exactly 1000 liters. The calculator automatically converts the volume to liters by multiplying by 1000.
Can I use this to calculate how much water a pool or tank holds?
Yes, as long as the pool or tank has one of the four shapes (for example cylindrical). For rectangular pools, see our dedicated pool volume calculator.