Sphere Volume Calculator

Volume equals four thirds times pi times the radius cubed. Because the radius is cubed, doubling it makes the volume eight times larger, so small changes in radius have an outsized effect on volume.

Surface area equals four times pi times the radius squared. For a radius of 3 the volume and the surface area happen to share the number 113.097336, which is a coincidence of that radius rather than a general rule.

Yes. The radius equals the cube root of three times the volume divided by four pi. The tool's engine includes this reverse calculation, so a sphere of a known volume can be turned back into a radius.

The radius, which is half the diameter. If you measured all the way across the sphere, divide that figure by two first. The tool also reports the diameter as a result so you can check your input.

It is unit free. If you enter the radius in centimeters, the volume is in cubic centimeters and the surface area is in square centimeters. Keep every input in the same unit for a consistent answer.

It is the distance around the sphere through its widest point, equal to two times pi times the radius. This is the same as the circumference of a flat circle with that radius, such as the equator of a globe.

Enter the radius in centimeters so the volume is in cubic centimeters, then divide by 1000, because one liter is 1000 cubic centimeters. A basketball of radius 12 cm holds a little over seven liters of air.

Not directly. It models a solid sphere. For a hemisphere, halve the volume and adjust the surface area for the flat face. For a hollow shell, calculate the outer and inner spheres and subtract.

The math uses the full value of pi and rounds to six decimal places for display, which is more precise than almost any physical measurement. The accuracy of your answer depends mostly on how well you measured the radius.