CBM & Dimensional Weight Calculator — Sea, Air & Courier Freight

The Formula

CBM (Cubic Meter) is the standard unit for freight volume. Dimensional (volumetric) weight converts package volume into an equivalent weight for billing. The divisor depends on the shipping mode: 6000 for air, 1000 for sea, 5000 for courier.

Variable Definitions

How to Use This Calculator

1. 1

   Enter the package dimensions (Length, Width, Height) and select the unit (cm, m, in, ft).

2. 2

   Enter the number of packages (defaults to 1).

3. 3

   Enter the actual weight of the shipment in kilograms.

4. 4

   Select the shipping mode: Air Freight, Sea Freight, or Courier/Express.

5. 5

   Review the CBM, dimensional weight, chargeable weight, and container estimates.

Common Applications

• Calculating total shipment volume in cubic meters for international freight shipping by air, sea, or courier
• Determining dimensional weight and chargeable weight to accurately estimate shipping costs and avoid unexpected surcharges
• Estimating how many standard 20-foot or 40-foot shipping containers are needed for a large export or import shipment
• Comparing shipping costs across air, sea, and courier modes by evaluating volumetric versus actual weight pricing

Chargeable weight is the greater of actual weight and dimensional weight — you pay for whichever is larger

Understanding the Concept

CBM (Cubic Meter) is the standard unit of volume measurement used in international freight shipping. It represents the space a shipment occupies in a container, truck, or aircraft cargo hold. One CBM equals the volume of a cube measuring 1 meter on each side. Freight carriers use the concept of "chargeable weight" to ensure they are compensated fairly for both heavy and light-but-bulky shipments. This is where dimensional weight comes in. Dimensional weight (also called volumetric weight) converts the physical dimensions of a package into a theoretical weight. The divisor varies by carrier and mode: air freight typically uses 6000 (cm³/kg), courier/express uses 5000, and sea freight uses 1000 (or equivalently, 1 CBM = 1000 kg). The chargeable weight is always the higher of the actual weight and the dimensional weight. For example, a large carton of styrofoam cups weighs very little but takes up substantial space — the dimensional weight would far exceed the actual weight, so you pay by volume. Conversely, a small crate of steel parts might have a dimensional weight well below the actual weight, so you pay by actual mass. Container estimates help you determine how many standard shipping containers your shipment will require. A 20-foot container holds approximately 33 CBM, while a 40-foot container holds approximately 67 CBM. These are maximum capacities — actual usable space is slightly less due to packing inefficiencies and container curvature.

Frequently Asked Questions

Sources & References