Worked example
Five boxes, each 24 × 18 × 12 inches.
- One box: 24 × 18 × 12 = 5,184 cubic inches.
- 5,184 ÷ 1,728 = 3.00 cubic feet per box.
- 3.00 × 5 = 15.00 cubic feet, which is 0.425 cubic meters.
The formula
Cubic inches = L × W × H (inches) Cubic feet = cubic inches ÷ 1,728 Cubic meters = cubic feet ÷ 35.3147 From centimeters: L × W × H ÷ 28,316.8 = cubic feet
The 1,728 comes from a cubic foot being 12 × 12 × 12 inches. It is the single most useful constant in domestic freight, because it turns a tape measure into a density figure.
What cubic feet are actually for
On its own, volume rarely prices a shipment. What it does is feed density, which is what LTL freight class is built on. Divide your weight in pounds by the cubic feet here and you have pounds per cubic foot, which reads straight off the NMFC scale.
It also sizes things: how much a moving truck holds, how much fits in a container, how much storage you need. Any time someone asks how big a shipment is, this is the number they mean.
Where cubic feet show up
Volume rarely prices a shipment on its own, but almost everything else in freight is built on it.
- Freight class. Divide your weight in pounds by the cubic feet here and you have density in pounds per cubic foot, which reads straight off the NMFC scale. This is the main use.
- Moving and storage. Rental trucks and storage units are sold in cubic feet, so this is how you work out what size you need.
- Container and trailer planning. A 53 ft dry van holds roughly 3,800 cubic feet; a 40 ft high cube holds about 2,700. Dividing your total volume by those figures gives a sanity check before anyone quotes.
- Warehouse costing. Storage is usually charged per pallet position or per cubic foot per month, so this is the number a 3PL quote is built from.
Cubic feet and cubic meters
Domestic US freight works in cubic feet; ocean and air freight work in cubic meters. One cubic meter is 35.3147 cubic feet, so a rough conversion is to divide cubic feet by 35 — close enough to sanity-check a quote, though not to send to a carrier.
Going the other way, one cubic foot is about 0.0283 cubic meters. A standard 48 × 40 × 48 inch pallet is 53.3 cubic feet, or 1.51 cubic meters, which is a handy figure to keep in mind when an overseas forwarder quotes per CBM and you think in pallets.
Common mistakes
- Dividing by 12 instead of 1,728. You are converting a volume, not a length, so the conversion is cubed.
- Measuring the product rather than the packed box. Freight occupies the outside of the carton.
- Ignoring the pallet. On palletized freight, measure the whole handling unit including the deck.
- Forgetting overhang. Cartons hanging over the pallet edge set the real length and width.
- Mixing units mid-calculation. Convert everything to one unit first, then multiply.
FAQ
How do I calculate cubic feet?
Multiply length by width by height in inches, then divide by 1,728. If you are already working in feet, just multiply the three together.
Why do I divide by 1,728?
Because a cubic foot is 12 by 12 by 12 inches, which comes to 1,728 cubic inches. Dividing by it converts a volume measured in inches into cubic feet.
How do cubic feet relate to cubic meters?
One cubic meter is about 35.31 cubic feet. Divide cubic feet by 35.3147 to get cubic meters.
Do I measure the box or the contents?
The box, at its outside dimensions, including any pallet or overhang. That is the space it occupies on a trailer, which is what you are billed for.
What do I use cubic feet for in freight?
Mostly density, which drives LTL freight class. Divide weight by cubic feet to get pounds per cubic foot, then read the class off the NMFC scale.
Rules last checked: Sep 24, 2026
Estimate only. Confirm with your carrier before booking.