Dimensional Weight Calculator
Dimensional (volumetric) weight of a parcel from its length, width and height at your carrier's divisor, and the chargeable weight, the greater of actual and dimensional, for one parcel size or a list of parcels.
Result…
How it's calculated
Dimensional weight = length × width × height ÷ divisor Chargeable weight = greater of actual weight and dimensional weight 1 lb = 0.45359237 kg
Carriers price space as well as weight: a large, light box takes room on a van or plane that a small heavy one does not. So they turn the box's volume into a dimensional (volumetric) weight by dividing it by a divisor, and charge the greater of that and the actual weight. The divisor is a density: 5,000 cm³ per kg means every 5,000 cubic centimetres counts as 1 kg. A larger divisor gives a lower dimensional weight. Divisors differ between carriers, services and countries, and some change them from time to time, so the options here are common values to check against your own carrier's rate guide, or enter its figure.
Your numbers, step by step
About the Dimensional Weight calculator
This dimensional weight calculator turns a parcel's size into the weight a carrier may charge for. It multiplies length × width × height, divides by the divisor you choose or enter, and compares the result, the dimensional or volumetric weight, with the actual weight: the greater of the two is the chargeable weight. It works in centimetres and kilograms or in inches and pounds, can round each side up to a whole unit as many carriers do, and takes one parcel size or a list of different parcels, giving totals parcel by parcel and on the whole shipment. Online sellers, small businesses and anyone sending a light but bulky box can use it to choose packaging and check a shipping quote. The divisors offered are common values: check the one your carrier and service use.
How to use it
- Choose the “Units”: centimetres and kilograms, or inches and pounds.
- Enter the length, width, height and “Actual weight per parcel”, or choose “A list of parcels” and type one parcel per line.
- Pick the divisor, or choose “Enter my carrier's divisor” and type the figure from your carrier's rate guide.
- Choose whether “Each side” is rounded up to a whole centimetre or inch, as your carrier does.
- Read the chargeable weight and whether you are billed on the actual or the dimensional weight.
Worked example
A box measures 50 × 40 × 35 cm and weighs 6 kg. Its volume is 50 × 40 × 35 = 70,000 cm³. At a divisor of 5,000 cm³ per kg, the dimensional weight is 70,000 ÷ 5,000 = 14 kg. That is more than the actual 6 kg, so the chargeable weight is 14 kg, about 30.86 lb.
Updated
Questions people ask
How do I calculate dimensional weight?
Multiply length × width × height and divide by your carrier's divisor. With centimetres and a divisor of 5,000, a 40 × 30 × 20 cm box is 24,000 ÷ 5,000 = 4.8 kg. With inches and a divisor of 139, a 12-inch cube is 1,728 ÷ 139 = 12.43 lb.
What divisor should I use?
The one in your carrier's rate guide for the service you book. FedEx's dimensional weight page, for example, gives 5,000 cm³ per kg, 305 in³ per kg and 139 in³ per lb. Other carriers and services, such as air freight, can use different figures.
What is chargeable weight?
The weight the price is based on: the greater of the actual weight and the dimensional weight. A small heavy parcel is charged on its actual weight; a large light one on its size.
How can I lower the dimensional weight of a parcel?
Use the smallest box that protects the item, since every centimetre or inch on each side is multiplied. Cutting a 50 × 40 × 35 cm box to 45 × 35 × 30 cm takes it from 14 kg to 9.45 kg at a divisor of 5,000.
Why might my carrier's figure differ from this result?
Carriers may round each side and the weight up, to the next 0.5 kg or whole pound for example, charge several parcels on totals rather than one by one, and change divisors from time to time. Their invoice is the final word; use the weight converter if your quote is in the other unit.