The air freight volumetric formula
Volumetric weight (kg) = length (cm) × width (cm) × height (cm) ÷ 6000
Measure each piece at its widest points, including pallets and packaging, multiply by the number of pieces and add up the shipment. The 6000 figure is a divisor in cubic centimetres per kilogram.
Why 1 CBM ≈ 167 kg
1 m³ = 1,000,000 cm³ 1,000,000 ÷ 6000 = 166.67 kg
So under the 6000 rule, every cubic metre of air cargo counts as at least 166.67 kg, often rounded to 167 kg. Cargo lighter than that per cubic metre is charged on volume.
Example
Four pieces of 120 × 80 × 100 cm, 150 kg each:
120 × 80 × 100 = 960,000 cm³ per piece 960,000 ÷ 6000 = 160 kg per piece 4 × 160 kg = 640 kg volumetric 4 × 150 kg = 600 kg actual Chargeable = 640 kg
Inch and pound formulas
Measured in inches, the same 6000 rule becomes a divisor of about 366 for kilograms or 166 for pounds:
Volumetric weight (kg) = L (in) × W (in) × H (in) ÷ 366 Volumetric weight (lb) = L (in) × W (in) × H (in) ÷ 166
Some services use other figures. Courier and express services commonly use 5000 cm³/kg (200 kg per CBM) or 139 in³/lb, which makes bulky parcels heavier on paper.
Check your carrier's divisor
6000 is a widely used planning value, not a universal law. Airlines, forwarders and contracts can set different divisors, and they decide how weights are rounded. Use the figure on your quote; every calculator here lets you change the divisor.
Reducing air freight volumetric weight
- Avoid oversized outer cartons and loose fill.
- Build pallets no taller than needed, as unused height still counts.
- Consider sea or road freight for light, bulky goods that are not urgent.
Calculate a multi-piece shipment with the Air Freight Chargeable Weight Calculator. The comparison with actual weight is explained in What Is Chargeable Weight?