A carton is billed on whichever is larger: the weight on the scale, or the weight its dimensions imply. Which one applies is decided by a divisor, and the divisor is decided by the channel. Get the divisor wrong and the freight quote is wrong by a third.
Freight · 6 min read · reviewed 2026-10-01
Volumetric weight is a conversion, not a measurement. It answers one question for the carrier: how much revenue should this space generate if the cargo were dense?
Volumetric kg = (L × W × H in cm) ÷ divisor
The divisor is the only variable, and it is set per channel rather than per shipment:
| Channel | Divisor | 1 cbm bills as | Note |
|---|---|---|---|
| DHL Express | 5,000 | 200.00 kg | Dimensional weight for parcels; compare against actual weight and bill the greater |
| FedEx Express | 5,000 | 200.00 kg | Applies to Express parcels; FedEx One Rate / envelope products use flat pricing |
| UPS | 5,000 | 200.00 kg | Daily rates use 5000; some contract rates still use 6000 — confirm on your agreement |
| TNT | 5,000 | 200.00 kg | Standard express divisor |
| SF Express | 6,000 | 166.67 kg | China-origin express commonly bills at 6000 |
| EMS / postal | 6,000 | 166.67 kg | Postal and ePacket channels typically use 6000 |
| Air freight (IATA) | 6,000 | 166.67 kg | 1 cbm = 166.67 kg. Air cargo bills the higher of actual and volumetric weight |
| Sea LCL | 1,000 | 1,000.00 kg | LCL bills on W/M — revenue ton = the greater of 1 cbm and 1000 kg |
| Road LTL | 3,000 | 333.33 kg | Road groupage often uses 1 cbm = 333 kg; varies by carrier |
Note the direction of the LCL row. Sea LCL bills on W/M — the revenue ton — which is the greater of one cubic metre and one metric tonne. That is exactly a divisor of 1000, because one cubic metre is 1,000,000 cm³, and 1,000,000 ÷ 1000 = 1,000 kg = one tonne.
5000 is the express-parcel convention: 1 cbm = 200 kg. 6000 is the air-cargo convention: 1 cbm = 166.67 kg. The number is not physics, it is a revenue assumption about how densely an aircraft or a van can be loaded, and different carriers made different assumptions.
The practical consequence is unpleasant and easy to forget: the same carton can be chargeable at 2,016,000 kg on one account and 1,680,000 kg on another — a difference of 336,000 kg, or roughly a fifth of the shipment — without anything about the goods changing. Some UPS contract rates still use 6000 while daily rates use 5000, so the number can differ between two quotes from the same company.
Always ask which divisor a quote was built on. It is the one line of a freight quote that a shipper can check in thirty seconds and that a salesperson will not volunteer.
Divide actual weight by volume and you get density in kg/m³. Compare it with the divisor's implied density — 200 kg/m³ at 5000, 166.67 kg/m³ at 6000. If your cargo is denser than that, you pay for weight and the volumetric calculation is irrelevant. If it is lighter, you are paying for air.
This shipment is 0.1 kg/m³ against 200 kg/m³, so it is volume-driven and the carton design is worth more than a freight negotiation. Two changes move the number without touching the product: reduce the carton's empty space, or nest or knock down the product so the same mass occupies less volume.
A useful target: get density at or above 200 kg/m³ and every kilogram you ship is a kilogram you are billed for. Below it, you are shipping packaging.
Measuring the carton, not the pallet. On LCL and air, the dimension used is the footprint actually occupied. A 1.2 × 1.0 m pallet with a 1.15 m stack occupies 1.38 cbm regardless of what the cartons inside add up to.
Ignoring carton bulge. A soft carton filled to the top measures wider than its flat dimension, and carriers measure the bulged carton. Five millimetres on each of three axes is a few percent of volume.
Minimum charges. Express has a minimum billable weight per consignment, so a small dense parcel and a small bulky parcel cost the same. On samples and spare parts this dominates the calculation.
Assuming LCL is cheaper because the volume is small. LCL carries fixed per-shipment charges — documentation, terminal handling, destination fees — that do not shrink with volume. Below a certain size the fixed charges per cbm rise faster than the freight falls, and a partial container becomes the more expensive option per unit.
Each one runs the arithmetic above on your own numbers. The guide explains why the figure is what it is; the tool produces it.
Volumetric Weight Calculator — the same engine that produced every figure on this page, with your carton, your route and your duty rate.
Length × width × height in centimetres, divided by the carrier divisor. At the standard 5000 divisor, one cubic metre is chargeable at 200 kg; at the air-freight 6000 divisor, 166.67 kg.
Volumetric weight is what the dimensions imply. Chargeable weight is the greater of volumetric and actual weight — that is the number the invoice is built on.
It depends on the divisor: 200 kg at 5000, 166.67 kg at 6000, 333 kg at 3000 for road LTL, and 1,000 kg for sea LCL revenue tons. There is no single correct answer without the channel.
No. FCL is priced per container regardless of how full it is, so volumetric weight is irrelevant — but packing density still decides your freight per unit, because it decides how many units fit in the box.
The guides that answer the question this one usually leads to.
Why the nominal cbm on a container spec is not the capacity you get, how packing and the weight ceiling decide the real count, and what pallets cost.
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