Surface Area To Volume Ratio Calculator

Work out surface area to volume ratio instantly with clear inputs, formula shown and shareable results.

About Surface Area To Volume Ratio Calculator

The surface-area-to-volume ratio falls as an object grows, since area scales with length² and volume with length³. For a sphere the ratio is exactly 3/r, and for a cube 6/a.

Formulas

Sphere

S/V = 4πr² / (⁴⁄₃πr³) = 3/r

Cube

S/V = 6a² / a³ = 6/a

Worked example

With the default values below, Surface Area To Volume Ratio Calculator returns Surface area to volume ratio of 0.600000. Change any input above and every figure here is recalculated in your browser.

Inputs used

Shapeone of Sphere, Cube, Cylinder (height = diameter): Sphere
Radius or edge lengthminimum 0: 5

Results

Surface area to volume ratio: 0.600000
Surface area: 314.1593
Volume: 523.5988
Characteristic length V/S: 1.6667

Step by step

1Values used
2Sphere
3Cube
4Surface area to volume ratio= 0.600000
5Surface area= 314.1593
6Volume= 523.5988
7Characteristic length V/S= 1.6667

Assumptions and limits

The result is derived only from the 2 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 6 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Sphere of radius 5?

3/5 = 0.6 per unit length.

Why does this matter biologically?

Heat loss and diffusion happen across the surface but demand scales with volume, which is why small animals lose heat faster and large cells need transport systems.