How to Calculate Cubic Volume
What is Cubic Volume?
Cubic volume measurements — cubic feet, cubic yards, cubic metres — are used in construction, shipping, and home improvement. Converting between units is essential when buying materials like concrete, gravel, or soil.
Formula
Cube: V = s³ | Rectangular prism: V = l × w × h | Sphere: V = (4/3)πr³
- V
- Volume (cubic units)
- s
- Side Length (units)
- r
- Radius (units)
Step-by-Step Guide
- 11 cubic yard = 27 cubic feet
- 21 cubic metre = 35.315 cubic feet
- 31 cubic foot = 7.48 gallons = 28.317 litres
- 4Volume = Length × Width × Height (all same unit)
Worked Examples
Input
10 ft × 8 ft × 3 ft room
Result
240 cubic feet = 8.89 cubic yards = 6.80 cubic metres
Input
1 cubic yard of concrete
Result
27 cu ft ≈ 45 × 60-lb bags or 34 × 80-lb bags
Frequently Asked Questions
How do I find the volume of irregular shapes?
For irregular shapes, use displacement method (water displacement for solids) or break into simpler shapes and add volumes.
What are cubic units?
Cubic units are volume measurements: cubic meters (m³), cubic feet (ft³), liters, gallons. Always track your units!
How does volume scale with size?
Volume scales with the cube of linear dimension. Double the side length = 8× the volume. This is why bigger objects hold much more.