How do I calculate cubic feet for shipping?

Multiply the package length × width × height in inches and divide by 1,728. For freight, do the same with feet directly. Most carriers also want CBM (cubic meters): multiply ft³ by 0.0283 to get CBM.

What is dimensional weight?

Dimensional (dim) weight is a billable weight calculated from package volume rather than actual weight. UPS/FedEx domestic: dim weight = (L × W × H in inches) ÷ 139. The carrier bills the greater of actual or dim weight.

How many cubic feet are in a 20 ft shipping container?

About 1,170 ft³ of usable space (33 CBM). A 40 ft container holds about 2,390 ft³ (67 CBM); a 40 ft high-cube container, 2,694 ft³ (76 CBM).

What is LCL shipping?

LCL (less-than-container load) is shared shipping for cargo under 15 CBM (~530 ft³). You pay for your portion plus a per-CBM rate; cargo travels with other shippers' goods. FCL (full container load) is for 15+ CBM consignments.

Shipping Cubic Feet Calculator — Dim Weight, Pallets & CBM for Freight

How to calculate cubic feet for shipping

Shipping calculations almost always start with cubic feet. Domestic parcel carriers (UPS, FedEx, USPS) use cubic inches and convert to dim weight. International freight forwarders use CBM (cubic meters), which is just 1/35.31 of a cubic foot. Pallets and crates use cubic feet directly.

For any package, multiply length × width × height in matching units. The calculator above accepts inches; convert with ÷ 1,728 to cubic feet, × 0.0283 to CBM.

Worked examples

Example 1: A 24 × 18 × 12 inch box

24 × 18 × 12 = 5,184 in³ ÷ 1,728 = 3 ft³ ≈ 0.0849 CBM. Dim weight: 5,184 ÷ 139 ≈ 37 lbs.

Example 2: A 48 × 40 × 60 inch pallet

48 × 40 × 60 = 115,200 in³ ÷ 1,728 = 66.67 ft³ ≈ 1.886 CBM.

Example 3: A 60 × 48 × 84 inch crate

60 × 48 × 84 = 241,920 in³ ÷ 1,728 = 140 ft³ ≈ 3.96 CBM.

Standard container capacities

Container / mode	Conversion factor	Worked example
20 ft container	~33 CBM	~1,170 ft³ usable
40 ft container	~67 CBM	~2,390 ft³ usable
40 ft high-cube	~76 CBM	~2,694 ft³ usable
45 ft high-cube	~86 CBM	~3,040 ft³ usable
Standard pallet (48×40×60 in)	~1.89 CBM	~66.67 ft³
EU pallet (1200×800×1500 mm)	~1.44 CBM	~50.85 ft³
Air ULD LD3	~4.3 CBM	~152 ft³
Air ULD LD11	~7.0 CBM	~247 ft³

Tips and considerations

Stack and pack efficiency

Containers don\'t fill to 100% capacity. Real-world freight forwarders pack to 80–90% of theoretical CBM. Plan accordingly when sizing a container or LCL booking.

Dimensional weight tricks

Lightweight bulky items (pillows, foam) usually bill on dim weight. Pack tightly and use vacuum bags to reduce billable volume on parcel shipments.

Common mistakes to avoid

Using inches for one dimension and feet for another. Shipping labels often list inches; calculations need consistent units. Convert everything to inches, multiply, divide by 1,728 for cubic feet.
Forgetting dimensional weight. Carriers charge whichever is greater: actual weight or dimensional weight (volume-based). For lightweight items in big boxes, dim weight wins.
Confusing CBM with CFT. International freight uses CBM (cubic meters); US carriers may use either. 1 CBM = 35.3 ft³.
Measuring item dimensions instead of package dimensions.Carriers bill the bounding box, not the item shape. A 24-inch round vase needs a 24-inch cube box.

Related concepts and calculators

Shipping math connects to a few other tools:

Cubic feet to CBM — required for ocean freight and most international shipments.
Cubic inches to cubic feet — package dimensions are usually in inches.
Cubic feet to pounds — for dimensional-weight calculations.
Moving calculator — for whole-household estimates.
Storage unit calculator — when goods need storage between shipments.