Volumetric Weight vs Actual Weight (Dimensional Weight)
Two shipments of identical size can be billed completely differently depending on weight. Here is how volumetric weight and actual weight differ, and which one decides your bill.
Actual weight is what your shipment weighs on the scale. Volumetric (dimensional) weight is what its size weighs — length × width × height in cm ÷ the carrier divisor (6000 for air, often 5000 for courier). Carriers bill the greater of the two, so a light but bulky parcel pays for the space it takes, not just its mass.
Actual weight
Actual weight (also called gross weight) is the simplest of the two: it is the total mass of your packed shipment, exactly as it reads on a scale, in kilograms or pounds. It includes the goods, the packaging and any pallet.
Volumetric (dimensional) weight
Volumetric weight — also called dimensional or DIM weight — answers a different question: how much would this volumeweigh if it were filled to the carrier's standard density? You calculate it from the dimensions:
volumetric weight (kg) = L × W × H (cm) ÷ divisor
The divisor encodes the assumed density. Air freight uses 6000, which treats one cubic meter as 167 kg. Express couriers often use 5000 (200 kg per CBM). A bigger divisor means a lower volumetric weight for the same box.
Worked comparison
Take one carton of 30 × 40 × 50 cm. Watch how the answer changes with the divisor and the actual weight:
| Scenario | Volumetric weight | Actual weight | Chargeable |
|---|---|---|---|
| Courier, divisor 5000 | 30×40×50 ÷ 5000 = 12 kg | 8 kg (light goods) | 12 kg (volumetric) |
| Courier, divisor 5000 | 30×40×50 ÷ 5000 = 12 kg | 18 kg (dense goods) | 18 kg (actual) |
| Air, divisor 6000 | 30×40×50 ÷ 6000 = 10 kg | 8 kg (light goods) | 10 kg (volumetric) |
Same box, three different bills. In the first row the cargo is light, so the volumetric weight (12 kg) governs; in the second the cargo is dense, so the actual weight (18 kg) governs. The larger number always wins.
Divisors by mode
| Mode / service | Divisor | Per CBM |
|---|---|---|
| Air freight (IATA standard) | 6000 | ≈ 167 kg |
| Courier / express (common) | 5000 | = 200 kg |
| Road freight (typical) | 3000–4000 | 250–333 kg |
How this becomes your bill
Volumetric weight is only half the story. Your chargeable weight — the figure your rate is actually multiplied by — is the greater of the actual and volumetric weights. For the full method and rounding rules, read how to calculate chargeable weight. And since volumetric weight is just CBM in disguise, the CBM guide is a useful companion.
Frequently asked questions
What is the difference between volumetric weight and actual weight?
Actual weight is what your shipment weighs on a scale. Volumetric (dimensional) weight is what its size weighs — the volume converted into kilograms using a carrier divisor. Carriers bill on whichever of the two is greater.
What is volumetric weight?
Volumetric weight, also called dimensional or DIM weight, estimates the weight a parcel's volume represents. You calculate it as length × width × height in centimeters divided by the carrier's divisor (6000 for air, often 5000 for courier).
Why do carriers use volumetric weight?
Space on an aircraft or truck is finite. Without dimensional weight, a large box of pillows would cost the same as a small box of bolts. Volumetric weight makes light, bulky cargo pay for the room it occupies.
Which weight do I actually pay for?
The chargeable weight — the greater of the actual weight and the volumetric weight. Dense cargo is usually billed on its actual weight; light, bulky cargo on its volumetric weight.
What divisor should I use?
Air freight uses 6000 (the IATA standard, ≈167 kg per CBM). Couriers and express services commonly use 5000 (200 kg per CBM). Road freight varies. Always confirm the divisor on your carrier's rate sheet.
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