Sphere Calculator

Enter a positive radius in any unit. The calculator returns volume in cubic units, surface area in square units, and diameter as twice the radius.

• Radius — distance from the center to any point on the surface.
• Keep units consistent — a radius in centimeters gives volume in cm³.

A sphere with radius 3:

• Diameter = 2 × 3 = 6
• Surface area = 4π × 9 ≈ 113.097
• Volume = (4/3)π × 27 ≈ 113.097

For r = 3 the volume and surface area happen to share the same numeric value (in different units).

• Volume — the space inside the sphere, (4/3)πr³.
• Surface area — the area of the outer skin, 4πr².
• Diameter — a straight line through the center; always 2r.

• Math is Fun — Sphere
• Wikipedia — Sphere