Volume of tanks and solids

How it is calculated

Box: V = length × width × height. Cylinder: V = π × diameter² ÷ 4 × height. Sphere: V = π × diameter³ ÷ 6.

Cone: V = π × diameter² ÷ 12 × height (a third of the cylinder). Pyramid: V = length × width × height ÷ 3. Truncated cone: V = π × h ÷ 3 × (R² + R·r + r²), with R and r the radii.

1 m³ = 1000 L. Example: a drum 0.57 m in inside diameter and 0.85 m tall: 3.1416 × 0.57² ÷ 4 × 0.85 = 0.217 m³ = 217 L.

Keep in mind

• Always measure inside: the walls of a masonry tank can take away 10-20 % of the capacity.
• A heap of grain or sand forms a cone whose slope is the material's angle of repose (about 25-35°): measure the base diameter and the height of the top.