Volume of a Sphere: V = ⁴⁄₃πr³ With Examples

The volume of a sphere formula is V = ⁴⁄₃πr³. Cube the radius, multiply by π, then by 4 ⁄ 3.

3D Solids r

Sphere

A sphere is the set of all points in space at distance r from the centre — a perfectly round ball.

Volume
V = (4 ⁄ 3) πr3
Surface area
SA = 4πr2
  • r radius
Download PDF sheetPDF · A4 · 1 page · 115 KB

Example 1: from the radius

A ball has a radius of 3 cm.

  • V = ⁴⁄₃πr³
  • V = ⁴⁄₃ × π × 3³ = ⁴⁄₃ × π × 27
  • V = 113.1 cm³

Example 2: from the diameter

A basketball is 24 cm across.

  • r = 24 ÷ 2 = 12 cm
  • V = ⁴⁄₃ × π × 12³ = ⁴⁄₃ × π × 1,728
  • V = 7,238.23 cm³ (about 7.2 litres)

Example 3: find the radius from the volume

A sphere holds 1,000 cm³. What is its radius?

  • 1,000 = ⁴⁄₃πr³
  • r³ = 1,000 × 3 ÷ (4π) = 238.73
  • r = ∛238.73 = 6.2 cm

Why does r get cubed?

Volume uses three lengths, so the radius appears three times. Double the radius and the volume grows 2³ = 8 times.

Live calculator

Try the sphere calculator

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Try it yourself

A marble has a radius of 1 cm. What is its volume?

Show the answer

V = ⁴⁄₃ × π × 1 = 4.19 cm³

Surface area is in our surface area of a sphere guide and on the sphere formulas page.

Download PDFPDF · A4 · 1 page · 115 KB

Volume of a sphere: FAQ

What is the volume of a sphere?

V = ⁴⁄₃πr³, where r is the radius.

How do I find the volume with the diameter?

Halve it to get the radius, or use V = πd³ ⁄ 6.

What happens to the volume if the radius doubles?

It becomes 8 times bigger, because 2³ = 8.

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