Sphere Volume Calculator

Calculate the volume and surface area of a sphere from its radius or diameter.

Sphere Dimensions

Choose whether you want to enter the radius or the diameter, then enter a positive value.

Sphere Volume & Surface-Area Formulas

A sphere is a perfectly round three-dimensional object where every point on its surface is the same distance (the radius) from its center. Its key measurements are derived directly from the radius.

  • Volume: V = (4 / 3) × Ï€ × r³
  • Surface area: A = 4 × Ï€ × r²
  • Great-circle circumference: C = 2 × Ï€ × r

Tip: Volume grows with the cube of the radius, so doubling the radius makes the sphere eight times larger in volume.

Radius vs. Diameter

The radius (r) is the distance from the center of the sphere to its surface. The diameter (d) is the distance straight across the sphere through its center. They are related by a simple formula:

  • Diameter from radius: d = 2 × r
  • Radius from diameter: r = d / 2

Real-World Examples

Sphere calculations appear in many everyday and scientific situations:

  • Finding how much water fills a spherical tank or a ball.
  • Estimating the surface area of a planet, balloon, or bubble.
  • Calculating the volume of bearings, marbles, or gas containers.
  • Comparing the size of objects such as planets, oranges, or sports balls.