Air cargo is billed on chargeable weight — the greater of your actual gross weight and the volumetric weight worked out from the carton's dimensions. Enter your carton size, weight and count to see which one wins and what the airline charges; the maths is exact, but confirm the divisor and pack spec with your forwarder before booking.
⚠️ Indicative — confirm the divisor and pack spec before booking. The maths is exact, but your real bill depends on the final carton size and gross weight confirmed at sampling, and on which volumetric divisor your carrier applies (6000 IATA vs 5000 express). Chargeable weight is always the greater of actual and volumetric weight — check your actual chargeable weight and rate with your freight forwarder before you book.
Airlines don't bill air cargo purely on the kilos your box weighs. They bill on chargeable weight — whichever is greater between the actual (gross) weight and the volumetric weight calculated from the carton's dimensions. Because knitwear is light and bulky, the volume side almost always wins, and a shipment that weighs little on the scale can still cost as if it were much heavier. This tool turns your carton size and weight into both figures so you can see which one drives the price.
Enter the carton's length × width × height in centimetres, its actual packed weight, how many cartons you're shipping, and the divisor your carrier uses. Everything updates as you type.
Nothing here is hidden or invented. The exact maths is:
Volumetric weight (kg) = (L × W × H in cm) ÷ 6,000
Chargeable weight = the greater of actual weight and volumetric weight
Total chargeable = chargeable per carton × number of cartons
Worked example (the default values): a 60 × 40 × 40 cm carton is 96,000 cm³. Divided by the IATA 6,000 divisor, that's 16 kg volumetric. The carton weighs 12 kg actual, so the chargeable weight is max(12, 16) = 16 kg — volume dominates. Switch the divisor to 5,000 and the same box becomes 19.2 kg volumetric, so the airline would bill 19.2 kg instead. Change any input and the numbers follow.
Aircraft holds run out of space long before they run out of lift, so carriers protect their capacity by charging for volume. The 6,000 divisor is IATA's way of converting cubic centimetres into a "weight" the hold can be sold by: one cubic metre is treated as 166.67 kg. Sweaters, cardigans and other knits are exactly the kind of low-density freight this rule targets — big cartons, modest weight. That's why the volumetric figure is usually the one to watch, and why compressing pack or right-sizing the carton can cut an air quote more than shedding actual kilos ever will. Express couriers using the 5,000 divisor tighten this further, so always match the divisor on your quote.
Volumetric weight in kilograms is length × width × height in centimetres, divided by 6,000 — the IATA standard divisor for scheduled air cargo. A 60 × 40 × 40 cm carton is 96,000 cm³, which divided by 6,000 gives 16 kg of volumetric weight. Some express and courier services divide by 5,000 instead, which produces a higher figure, so always check which divisor your carrier uses.
Chargeable weight is the greater of your actual (gross) weight and your volumetric weight — the airline bills whichever is higher. Knitwear is light and takes up a lot of room, so the volumetric figure usually wins: a carton that weighs 12 kg on the scale but measures 16 kg volumetric is charged as 16 kg. You are paying for the space the box occupies in the aircraft hold, not only the kilos it weighs.
6,000 is the IATA standard divisor for scheduled air cargo and is the default here. Many express couriers and some consolidators use 5,000, which makes the volumetric weight — and therefore the bill — higher for the same box. This tool lets you switch between the two so the result matches your carrier's rule; when in doubt, ask your freight forwarder which divisor is on your quote.
Use your own figures from the factory. At Kiwi Giyim we confirm the exact export-carton dimensions, gross weight and pack ratio at the sampling stage, so you can price freight against real numbers rather than guesses. Until you have those figures, enter a realistic estimate — this tool only does the maths on the values you give it and invents nothing.
Related free tools: Carton & CBM Shipment Calculator and Knitwear Lead-Time Estimator — or browse all free tools.