Carton Gross & Volumetric Weight Calculator
Determine actual gross carton weight and airfreight volumetric dimensional chargeable weight.
Every carton has two weights that matter, and they answer different questions. Gross weight is what the carton actually weighs on a scale, and it governs sea freight payload and handling. Volumetric weight is what the carton counts as for air freight billing, and it governs what the airline charges. The airline bills the higher of the two, so a light, bulky carton can cost far more to fly than its scale weight suggests. Use this tool with the Container Loading Estimator, which needs the gross weight to check payload limits.
What is Carton Weight Calculation?
Carton weight calculation finds three figures for one packed master carton: its gross weight, its air volumetric weight, and its chargeable weight. Gross weight is the net weight of the garments inside plus the tare weight of the empty carton. Volumetric weight converts the carton size into a weight equivalent for air freight, using the divisor built into the tool. Chargeable weight is simply the higher of the two, and it is the figure an airline bills on.
The distinction matters most for light garments. T-shirts, knitwear and light blouses pack a lot of air into a carton, so their volumetric weight routinely exceeds their scale weight. A factory that quotes air freight on gross weight alone will underprice the shipment and absorb the difference, which is why both figures must be known before a price is confirmed.
Formula
Gross kg = (Net grams per piece × Pieces per carton + Tare grams) / 1000 Volumetric kg (air) = Length cm × Width cm × Height cm / 6000 Chargeable kg = higher of Gross kg and Volumetric kg
- Net grams per piece: average garment weight in grams, weighed on a sample across sizes.
- Pieces per carton: garment count packed in one master carton.
- Tare grams: weight of the empty carton, including board and any inner packing. The tool opens with 800 grams; replace it with your measured carton.
- Length, Width, Height: outside carton dimensions in centimetres.
- 6000: the air volumetric divisor used by this tool. Carriers vary, so confirm the divisor your carrier applies.
- Results: gross weight also shown in pounds, using 1 kg = 2.20462 lbs, both to two decimals.
How to Calculate
- Weigh a sample of garments and enter the average net weight per piece in grams. Weigh across sizes, because one size alone misstates the average.
- Enter the pieces packed per master carton.
- Enter the empty carton tare weight in grams, weighed on your own carton rather than accepting the 800 gram placeholder blindly.
- Enter the carton outside length, width and height in centimetres.
- Read gross weight, air volumetric weight and chargeable weight. If the result says dimensional volume billing, the carton is billed on its size, not its scale weight.
Example
Take the illustrative carton used across this batch: 24 pieces at a net 220 grams each, in a 60 × 40 × 30 cm carton with an 800 gram tare. Gross weight is (220 × 24 + 800) / 1000 = 6,080 / 1000 = 6.08 kg, which is 13.40 lbs. Volumetric weight is 60 × 40 × 30 / 6000 = 72,000 / 6000 = 12.00 kg. Chargeable weight is the higher figure, 12.00 kg, billed on a dimensional basis, nearly double the 6.08 kg scale weight.
The same carton shows the sea freight contrast. For a sea container, the payload check uses the 6.08 kg gross weight, and the Container Loading Estimator allows 4,358 such cartons by weight in a 40-foot High Cube, far above the 944 allowed by volume, so volume governs at sea. For air, the same carton bills at 12.00 kg. One carton, two billing logics, which is why the tool reports both figures instead of one.
Assumptions
This calculation assumes one average net weight per piece, so size-wise weight variation is averaged out; weigh a proper sample rather than one piece. It assumes the entered tare weight is your carton, not the 800 gram placeholder, and that carton dimensions are outside measurements. It assumes the air divisor of 6000 built into the tool; some carriers use a different divisor, which changes the volumetric figure directly, so confirm it before quoting. The chargeable figure applies the air rule only and does not model sea freight, minimum billable weights, or carrier rounding rules.