Boxes, rooms and storage
Cubic Feet Calculator
Enter length, width and height to calculate cubic feet. Add different item sizes and quantities to get one total.
Each item can use its own measurement unit. For feet + inches, leave an unused part blank; each full dimension must be greater than zero.
Enter your dimensions
Explore volume calculators
How to calculate cubic feet
For a rectangular box or space, multiply the length, width and height after converting every measurement to feet:
Volume (ft³) = length (ft) × width (ft) × height (ft)
One cubic foot is a cube with sides of one foot. It is a unit of volume; square feet measure area.
Example: a box measured in inches
A box measuring 24 × 18 × 12 inches is 2 × 1.5 × 1 feet. Its volume is 3 ft³. Five boxes of that size have a combined volume of 15 ft³.
Feet and inches together
A length of 2 ft 6 in is 2 + 6/12 = 2.5 feet. A box measuring 2 ft 6 in × 1 ft 6 in × 1 ft has a volume of 3.75 ft³. Enter whole feet and decimal inches, or choose decimal feet.
More than one box size
Calculate each size separately, multiply by its quantity, then add the row totals. For example, five 3 ft³ boxes plus two 3.75 ft³ boxes give 22.5 ft³.
Cubic feet conversions
| Convert ft³ to | Calculation |
|---|---|
| Cubic yards (yd³) | Divide by 27 |
| Cubic inches (in³) | Multiply by 1,728 |
| Cubic meters (m³) | Multiply by 0.028316846592 |
| Liters (L) | Multiply by 28.316846592 |
When all dimensions are in inches, multiply them and divide by 1,728. When all dimensions are in centimeters, multiply them and divide by 28,316.846592.
Storage volume and usable capacity
For shipping or storage, measure the outside dimensions of each package. For the space inside a container, use its inside dimensions. Gaps between boxes, packing materials and irregular shapes can make the space you need larger than the sum of the box volumes.
This calculator handles rectangular spaces. For a cylinder, sphere or another shape, use the volume calculator. For one rectangular object with more capacity units, use the box volume calculator.
Can square feet be converted to cubic feet?
You also need a height or depth. For example, an area of 100 ft² with a depth of 0.5 ft has a volume of 50 ft³. Area alone does not determine volume.
Results are rounded for display. Calculations use unrounded measurements and exact international foot and inch definitions.