What is the Cubic Feet of a Rectangle Calculator?
This calculator finds the volume of a rectangular box (also called a cuboid or rectangular prism) in cubic feet. Cubic feet measure three-dimensional space — how much a box, container, room, freezer, shipping crate or planter can hold. As long as your length, width and height are all in feet, the result is in cubic feet (ft³).
How to use it
Enter the three dimensions of your box — length, width and height — in feet. The calculator multiplies them together and instantly shows the volume in cubic feet, along with the equivalent in cubic yards and cubic inches. If your measurements are in inches, divide each by 12 first to convert to feet.
The formula explained
The volume of any rectangular box is simply the product of its three perpendicular dimensions:
$$V = \text{Length (ft)} \times \text{Width (ft)} \times \text{Height (ft)}$$Because all three sides share the same unit (feet), multiplying them gives a result in feet³. To convert, divide cubic feet by 27 for cubic yards, or multiply by 1,728 for cubic inches.
Worked example
Suppose you have a storage box that is 5 ft long, 4 ft wide and 3 ft tall. The volume is \(5 \times 4 \times 3 = 60\) cubic feet. That equals \(60 \div 27 \approx 2.22\) cubic yards, or \(60 \times 1{,}728 = 103{,}680\) cubic inches.
FAQ
What if my measurements are in inches? Convert each dimension to feet by dividing by 12 before entering them, or measure in feet directly.
Does the order of length, width and height matter? No. Multiplication is commutative, so any order produces the same volume.
How do I find gallons from cubic feet? Multiply cubic feet by about 7.48 to estimate US liquid gallons of capacity.
