09/10/2026
π¦ Supplier says 10 kg. Carrier bills 25 kg. Who's cheating?
Nobody. This is volumetric weight.
Carriers sell space, not just weight. Box length Γ width Γ height Γ· divisor = volumetric weight, and billing weight is always the higher of actual and volumetric.
Γ· 5,000 β DHL / FedEx / UPS
Γ· 6,000 β Air and sea freight
Γ· 8,000 β ePacket / China Post (under 10 kg)
Example: a 50 Γ 50 Γ 50 cm box = 125,000 cmΒ³ Γ· 5,000 = 25 kg. Actual weight 10 kg, so it bills at 25.
Same box. 2.5Γ the cost.
The part that stings: your freight cost was decided when the box got packed.
If the supplier sized that box for a 20 kg product, you're paying for the air inside it. Cutting 2 cm off each side usually drops volumetric weight by 20-30%.
Plush toys, pillows and storage bins are the worst offenders. A 40 Γ 40 Γ 40 cm box at 2 kg actual bills around 12.8 kg by air - a 6x markup, applied completely correctly. There's no one to argue with.
Want to run your own numbers? Dimensions in, chargeable weight out.
https://www.alleasyscm.com/calculator-volumetric-weight/
What box size does your supplier usually use? Drop it below.
Calculate volumetric (dimensional) weight for air, sea, rail, and express shipping. Free calculator + 3 manual examples + carrier comparison (DHL, FedEx, UPS).