Guide · Air
Air freight chargeable weight.
The chargeable weight of an air shipment is the weight it is billed on: the greater of the actual weight and the volumetric weight. The volumetric weight follows the IATA rule that treats 6,000 cm³ as 1 kg. A light, bulky shipment therefore pays for the space it takes up on the aircraft.
What chargeable weight is
It is the weight used to calculate the air freight charge: the greater of the shipment's actual gross weight and its volumetric weight. The criterion of 6,000 cm³ per kg is set by the IATA TACT rules, and each airline applies it in its tariffs and conditions. Confirm the divisor and rounding with your airline or forwarder.
Who it applies to
Anyone who ships air cargo, through each airline's conditions of carriage. That is why it pays to read your airline's: the volume criterion is IATA's, but the rounding can differ.
How to calculate it
| Step | Calculation |
|---|---|
| 1. Measure the shipment | Length × width × height in cm, at the longest points. |
| 2. Volumetric weight | Volume in cm³ ÷ 6,000 = kg (equivalent to 166.67 kg per m³; converted to imperial units, the same rule is about 10.4 lb per ft³). |
| 3. Actual weight | The gross weight of the shipment on the scale. |
| 4. Chargeable weight | The greater of the two. |
Examples
Here is how the rule applies to three different shipments:
| Shipment | Dimensions (cm) | Actual weight | Volumetric weight | Chargeable weight |
|---|---|---|---|---|
| Light box | 60 × 40 × 50 | 8 kg | 120,000 ÷ 6,000 = 20 kg | 20 kg (volumetric) |
| Heavy pallet | 120 × 80 × 60 | 300 kg | 576,000 ÷ 6,000 = 96 kg | 300 kg (actual) |
| 3 identical boxes | 80 × 60 × 50 (× 3) | 3 × 25 = 75 kg | 3 × 40 = 120 kg | 120 kg (volumetric) |
- Light, bulky cargo: pays for its volume; the light box is billed on more than twice its actual weight.
- Dense cargo: the scale decides; reducing the packaging does not change the bill.
- Several packages: add up the volumetric weights and the actual weights of all packages, then compare the two totals.
- In cubic metres: multiply by 166.67 (1,000,000 cm³ ÷ 6,000). For example, 0.576 m³ × 166.67 ≈ 96 kg.
Express courier and rounding
Express courier services often use 5,000 instead of 6,000; confirm the divisor with your carrier. With the 80 × 60 × 50 cm box: in air cargo, 240,000 ÷ 6,000 = 40 kg; with 5,000, 240,000 ÷ 5,000 = 48 kg. A smaller divisor gives a higher volumetric weight.
Rounding also depends on the airline: some round to the whole kilo and others to the half kilo. A 50 × 40 × 35 cm box weighing 9 kg gives 70,000 ÷ 6,000 = 11.67 kg volumetric; the final figure depends on that rounding.
Run these numbers with your own dimensions in the air volumetric weight calculator.
Common mistakes
- Using average dimensions instead of the largest: measure each package at its longest points.
- Assuming a rounding rule: some airlines round to the whole kilo and others to the half kilo. Check their conditions.
- Forgetting that chargeable weight is the basis of the rate, not the rate: the price is set by your airline or forwarder.
See also chargeable weight and volumetric weight in the glossary.
Sources
- IATA, The Air Cargo Tariff and Rules (TACT)
Last reviewed: