Volumetric (Desi) Weight Calculator

What Is Volumetric (Desi) Weight?

In freight and shipping, pricing isn't always based on actual weight. Light but bulky shipments — items that look small but take up a lot of space, like pillows, toys, or packaging material — consume a vehicle's or aircraft's capacity by volume rather than by weight. That's why carriers use a calculation called volumetric weight (known as "desi" in Turkish logistics terminology): a package's length, width, and height in centimeters are multiplied together and divided by a coefficient. The result is a notional weight that reflects how much space the shipment occupies, independent of its actual weight in kilograms.

The billed weight (payable weight) is whichever is higher: the actual weight or the calculated volumetric weight. A light but bulky shipment can end up billed at a much higher rate than its real weight would suggest. Calculating volumetric weight before shipping is the most practical way to avoid surprise costs.

The coefficient varies by transport mode and carrier. For domestic road freight, 3000 is the most common coefficient; some carriers use 4000 or 5000. International express couriers commonly use 5000, and air cargo uses the IATA standard of 6000. The higher the coefficient, the lower the calculated volumetric weight for the same volume — so a carrier with a higher coefficient is generally more favorable for bulky-but-light shipments.

Turning the coefficient into kilograms per cubic metre makes comparison easier: 1,000,000 ÷ coefficient. A 3000 coefficient means 1 m³ = 333 kg, 4000 means 250 kg, 5000 means 200 kg and 6000 means 167 kg. For large shipments such as pallets, carriers usually quote this kilograms-per-cubic-metre ratio instead; the calculation is the same.

The most effective way to reduce volumetric weight costs is to optimize packaging: use boxes that fit the product closely rather than leaving empty space, nest parts where possible, and pack close to standard box dimensions when you can — this reduces both the volumetric charge and wasted space on the vehicle or pallet. The calculator above lets you compare multiple box line items at once and instantly see the billed weight under different carrier coefficients.

For example, take a box measuring 40×30×30 cm with an actual weight of 6 kg. Its volume is 36,000 cm³; divided by a coefficient of 3000, the volumetric weight comes out to 12 kg — since that's higher than the actual weight, the billed weight is 12 kg, not 6 kg. If the same box ships with a carrier using a 5000 coefficient, the volumetric weight is 7.2 kg, still higher than the 6 kg actual weight, so the billed weight is set at 7.2 kg.

How volumetric weight is calculated

Dimensions are in centimetres and the result is in kilograms. The coefficient depends on the carrier's pricing policy: the higher it is, the less the same volume costs you. Billed weight is worked out per item and then summed — one box in a shipment can be billed on its actual weight while another is billed on its volume.

Worked example: a 40×30×30 cm box weighing 6 kg

Suppose you are sending a single box measuring 40×30×30 cm with an actual weight of 6 kg.

1. Volume: 40 × 30 × 30 = 36,000 cm³.
2. Volumetric weight at a 3000 coefficient: 36,000 ÷ 3,000 = 12 kg.
3. Billed weight: the greater of the actual 6 kg and the volumetric 12 kg, so 12 kg.
4. The same box with a carrier using 5000: 36,000 ÷ 5,000 = 7.2 kg volumetric, so billed weight drops to 7.2 kg.

Result: the box weighs 6 kg but you pay for 12 kg at a 3000 coefficient — twice as much. The identical shipment costs 40% less with a carrier on 5000.

Frequently asked questions

What is volumetric weight?

Volumetric weight expresses the space a shipment takes up as if it were weight. Carriers use it to price light-but-bulky goods fairly, since those fill a vehicle long before they reach its weight limit. It is also called dimensional or DIM weight, and in Turkey it is known as desi.

How do you calculate volumetric weight?

Multiply the three sides of the box in centimetres and divide by the carrier's coefficient: (length × width × height) ÷ coefficient. A 40×30×30 cm box comes to 12 kg at a 3000 coefficient.

Which coefficient should I use?

Domestic road freight most often uses 3000. International road and sea shipments also use 4000 and 5000, and air freight uses the IATA standard of 6000. The calculator compares all four side by side: 3000, 4000, 5000 and air freight's 6000. Always confirm the exact figure against your carrier's tariff.

Why am I paying for more than the box actually weighs?

Because the carrier bills whichever is greater, the actual weight or the volumetric weight. For light, bulky goods the volumetric figure almost always wins — with cushions, furniture parts or packaging materials the gap can be several times over.

How can I reduce volumetric weight costs?

The only real lever is reducing volume. Taking 2 cm off each side of a 40×30×30 cm box brings it from 36,000 cm³ down to 29,792 cm³, so the volumetric weight falls from 12 kg to 9.9 kg — about 17% off. Choosing a box that fits the product closely, cutting void fill and consolidating orders into one carton all show up directly on the invoice.

Are volumetric weight and desi different things?

No, they are two names for the same calculation. “Desi” is the established term in Turkey, while English-language sources say volumetric weight or dimensional (DIM) weight. The formula and the logic are identical; only the coefficient varies by carrier.

What does a coefficient mean in kilograms per cubic metre?

Divide 1,000,000 by the coefficient: 3000 gives 1 m³ = 333 kg, 4000 gives 250 kg, 5000 gives 200 kg and 6000 gives 167 kg. The "1 m³ = 333 kg" rule used for road groupage is simply the 3000 coefficient.

How do you calculate volumetric weight for a pallet?

With the same formula, using the outside dimensions including the pallet itself: a 120 × 80 × 150 cm Euro pallet comes to 480 kg at a 3000 coefficient. If it actually weighs less than 480 kg, it's billed at 480 kg. The pallet volume guide goes into more detail.