How to use the volume calculator
Choose a rectangular box or cylinder and enter dimensions in the same unit. Volume is three-dimensional, so the result is in cubic units.
Volume formulas
If all dimensions are in feet, the result is cubic feet. Converting cubic units requires cubing the linear conversion factor.
Example: Leo measures a storage box
Leo measures a rectangular box as 10 inches long, 8 inches wide, and 6 inches high. Volume is 10 × 8 × 6 = 480 cubic inches.
Use internal dimensions to estimate usable capacity. This result describes geometric volume, not how tightly irregular objects will fit inside.
Keep all three dimensions in the same unit
A box measuring 10 × 8 × 6 has a volume of 480 cubic units. A cylinder uses π × radius² × height; enter half the diameter as its radius.
Dimensions in centimeters produce cubic centimeters, while dimensions in feet produce cubic feet. These results are volume, not automatically liters or gallons.
Convert cubic units after finding the volume
Volume uses three dimensions, so the unit conversion factor must also be cubed. One cubic foot is 12 × 12 × 12 = 1,728 cubic inches. One cubic meter is 1,000 liters.
For a cylinder, enter the radius, which is half the diameter, and the perpendicular height. A container's usable capacity can be lower than its ideal geometric volume because of wall thickness or an unfilled space.
Assumptions and limitations
What the estimate assumes
Does not calculate capacity in gallons or liters automatically.
Volume Calculator FAQs
Why is volume measured in cubic units?
Volume uses three dimensions, so the measurement unit is multiplied three times.
How do I calculate box volume?
Multiply length, width, and height.
How do I calculate cylinder volume?
Multiply pi by radius squared and by height.
Can I mix inches and feet?
Convert all dimensions to the same unit before calculating.
General geometry calculator. Use consistent measurement units.