Shipping & logistics
Convert package volume into a chargeable shipping weight.
Enter your numbers to see the answer.
Volumetric weight calculator guide
Volumetric weight is the courier’s answer to a big box that weighs very little: the carrier converts package volume into a weight using a divisor, then bills whichever is higher, the scale weight or the volumetric weight. This calculator multiplies length, width, and height in centimetres and divides by the divisor you choose. The default of 5,000 cm³ per kg is the rule most express couriers apply to international parcels; air cargo consolidators use 6,000. Sellers shipping cross-border parcels use this page to see why a light pillow or lampshade is billed at three times its actual weight and to test how a smaller box changes the outcome. The result is an estimate of the volumetric side only. Compare it with the parcel’s real weight, then check the carrier’s rounding rule, because some round each dimension up to the next centimetre and the result up to the next half kilogram before pricing.
Volumetric weight (kg) = length (cm) × width (cm) × height (cm) ÷ divisor (cm³/kg). Package volume (m³) = length × width × height ÷ 1,000,000.
Worked example: a parcel 50 cm × 40 cm × 40 cm has a volume of 50 × 40 × 40 = 80,000 cm³, which is 0.08 m³. With the default express divisor of 5,000, volumetric weight is 80,000 ÷ 5,000 = 16 kg. If the same box actually weighs 9 kg, the courier bills 16 kg. Switching to the air cargo divisor of 6,000 gives 80,000 ÷ 6,000 = 13.33 kg. At the default the calculator displays 16 kg.
Enter dimensions in centimetres and a divisor in cubic centimetres per kilogram; the result is kilograms. Inch-based rules are different numbers for the same rule: a divisor of 139 in³/lb is equivalent to about 5,000 cm³/kg, and 166 in³/lb is equivalent to about 6,000 cm³/kg. Do not enter inches with a metric divisor. Convert inches to centimetres by multiplying by 2.54.
Carriers bill on whichever is greater, actual weight or volumetric weight, so treat this result as the number to compare against your carrier's own quote. Divisors, rounding rules, and surcharges differ between carriers and between domestic and international services, and they change with contract terms. Confirm the current rules for your account before you price a shipment. On this page the figure rests entirely on length, width, height, divisor, market / jurisdiction, effective date, data source, update owner and review date, so start there if the volumetric weight calculator returns something you did not expect.
Good to know: measure the outside of the packed box at its widest points, including bulges and the lid, not the box manufacturer’s inside dimensions. Do not assume 5,000 is universal; domestic parcel services, freight, and negotiated accounts use other divisors, and some carriers switch to 4,000 for certain lanes. Enter the divisor, not the density: 5,000 is cm³ per kg, so a larger divisor produces a lower volumetric weight.
Shipping results depend on carrier, service, route, divisor, rounding, surcharges, and contract terms. Confirm the current carrier rule before buying a label or quoting a customer.
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How it works
Convert package volume into a chargeable shipping weight. This tool explains the calculation so you can adjust the assumptions to match your situation.
Worked example
With Length = 50 cm · Width = 40 cm · Height = 40 cm · Divisor = 5000 → 16 kg (volumetric weight). Change an input above and this example updates with your numbers.
Common questions
Multiply the length, width, and height of the package in centimetres and divide by the carrier divisor. Using 5,000, a 50 × 40 × 40 cm box has a volumetric weight of 80,000 ÷ 5,000 = 16 kg.
Both are cubic centimetres per kilogram. Express couriers such as DHL Express, UPS, and FedEx international services generally use 5,000; IATA air cargo uses 6,000. The 5,000 divisor produces a volumetric weight 20% higher for the same box.
The greater of the two, often called chargeable or billable weight. If the parcel’s scale weight is above the volumetric figure, the volumetric calculation changes nothing. If it is below, you pay for the space the box occupies.
A divisor of 139 cubic inches per pound equals about 5,022 cubic centimetres per kilogram, so a US 139 rule and a metric 5,000 rule bill almost the same weight. USPS’s 166 in³/lb is close to the 6,000 cm³/kg air cargo rule.
Use the smallest box that protects the item, remove void fill that adds height, and ship flat items flat. Reducing a 50 × 40 × 40 cm box to 50 × 40 × 30 cm cuts the volumetric weight from 16 kg to 12 kg at a 5,000 divisor.