Volumetric Weight Calculator
Calculate volumetric weight in kilograms from your box size using the cm³/kg divisor your carrier applies, and see the chargeable weight.
How volumetric weight works
Volumetric weight (the metric name for dimensional weight) turns the space a parcel takes up into a billable weight in kilograms. Couriers compare it against the scale weight and charge on whichever is greater, so a large, light box is not under-billed.
The formula uses a cm³/kg divisor:
volumetric weight (kg) = (L × W × H in cm) ÷ divisor
This page defaults to the generic courier divisor of 5000 cm³/kg, the value used by FedEx, UPS and DHL on international metric shipments. Air freight under IATA uses a larger 6000 cm³/kg divisor, which yields a lower volumetric weight for the same box.
Worked example (page defaults)
Using the default carton of 50 × 40 × 30 cm:
- Volume:
50 × 40 × 30 = 60,000 cm³ - Volumetric weight:
60,000 ÷ 5000 = 12 kg
If the box weighs 8 kg on the scale, you are billed on the 12 kg volumetric figure. If it weighs 18 kg, actual weight wins. That actual-vs-volumetric comparison is exactly what the chargeable weight calculator returns.
Switch the same box to the 6000 air-freight divisor and it drops to 60,000 ÷ 6000 = 10 kg.
Divisor reference (metric)
| Carrier / mode | Divisor (cm³/kg) | 50×40×30 cm result |
|---|---|---|
| Generic / courier | 5000 | 12 kg |
| FedEx / UPS (international) | 5000 | 12 kg |
| DHL Express | 5000 | 12 kg |
| Air freight (IATA) | 6000 | 10 kg |
The key relationship: a bigger divisor means a lighter volumetric weight. The 6000 air divisor is more generous than the 5000 courier divisor.
Reducing volumetric weight
The divisor is fixed by the carrier, so the only thing you control is the cubic size. Trim the carton to the goods, remove void fill, and avoid stepping up a box size unnecessarily. To work the same numbers in pounds and inches, use the dimensional weight calculator; to total a mixed shipment's cubic metres first, use the CBM calculator. For a DHL-specific page, see the DHL volumetric weight calculator.