Sphere Calculator

Enter any one value — radius, diameter, volume, surface area, or circumference — and all others are calculated instantly

Unit
← Click a symbol to use it as input
r
Radius
cm
IN
d
Diameter
cm
V
Volume
cm³
A
Surface Area
cm²
C
Circumference
cm
r Radiusd DiameterV VolumeA Surface AreaC Circumference
◯
Enter any one value above to calculate all sphere properties

What is a sphere calculator?

The sphere calculator is an online tool that computes key geometric properties of a sphere, making complex 3D math fast and accurate.

 

What does it typically calculate?

Most sphere calculators let you input one value (like the radius) and instantly get the others. Common outputs include:

  • Radius (r): Distance from the center to any point on the surface.
  • Diameter (d): Twice the radius (d = 2r).
  • Circumference (C): Length of a great circle around the sphere (C = 2πr).
  • Surface area (A): Total area of the outer surface (A = 4πr²).
  • Volume (V): Space enclosed inside the sphere (V = (4/3)πr³).

 

How does it work?

You enter a known value (e.g., radius, volume, surface area, or circumference), and the tool uses the standard sphere formulas to solve for the unknowns. Results often appear both exactly (in terms of π) and approximately (with a decimal value for π ≈ 3.14159).

 

What is a sphere?

A perfectly round 3D shape in which every point on the surface is the same distance from the center.

 

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Related: Cylinder volume

Radius of a circle.