Instant volume and surface area for any sphere radius
Sphere Calculator
Volume = (4/3) × π × r³
Surface Area = 4 × π × r²
Diameter = 2 × r
Circumference = 2 × π × r
A sphere calculator computes volume, surface area, diameter, and circumference from a single radius value. Whether you are a student solving geometry homework, an engineer sizing a tank, or a designer scaling a 3D object, this free online tool gives you all four sphere measurements instantly — with unit conversion across metric and imperial systems.
The volume of a sphere is V = (4/3) × π × r³, where r is the radius. For example, a sphere with radius 5 cm has a volume of approximately 523.6 cm³.
Surface area = 4 × π × r². A sphere with radius 5 cm has a surface area of approximately 314.16 cm². This is the total area of the outer shell.
Volume measures the three-dimensional space enclosed inside the sphere (in cubic units), while surface area measures the two-dimensional outer skin (in square units). They use different formulas and scale at different rates as the radius grows.
Yes. You can enter the radius in any unit — millimeters, centimeters, meters, kilometers, inches, feet, yards, or miles — and choose a different unit for the output. The calculator handles the conversion automatically, including squaring or cubing the conversion factor for area and volume.