What is Volumetric Weight? Calculation Guide & Formula (2026)
The volumetric weight explained by Secursus.
In logistics and in the transportation field, package weight is important, but so is the space that a particular package expedited takes up. For some shipping carriers like UPS or FedEx, the package dimensions have a huge impact on the shipping price in addition to the package weight.
The volumetric weight (or dimensional weight) is a pricing principle that allows carriers to set the shipping price according to the shipment volume, in addition to their actual weight and dimensions.
Indeed, when you think about it: a kilogram of feathers weighs the same as a kilogram of lead, but the space occupied by the package will not be the same. This is where the volumetric weight comes in!
1. What is Dimensional Weight vs. Actual Weight?
Also called "DIM weight" or "volume weight", the volumetric weight represents the volume occupied by a package in a truck or plane.
Carriers always compare two numbers:
- Actual Weight: What the scale says (e.g., 5 kg).
- Volumetric Weight: The calculated size (e.g., 8 kg).
The Rule: The carrier will always charge you for the higher of the two numbers. This is known as the "Billable Weight."
2. How to Calculate Volumetric Weight (Formulas)
To determine the volumetric weight, you need the length (L), width (W), and height (H) of the package. The formula depends on whether you measure in Metric (cm) or Imperial (inches).
The Metric Formula (cm / kg)
Used by DHL Express and most international couriers.
Volumetric Weight (kg) = (Length x Width x Height in cm) / 5000
Example: A box is 30 x 26 x 13 cm. (30 x 26 x 13) / 5000 = 2.03 kg. Even if the box weighs 1 kg on the scale, you will be billed for 2.03 kg.
The Imperial Formula (inches / lbs)
Used by UPS, FedEx, and USPS in the USA.
Dimensional Weight (lbs) = (Length x Width x Height in inches) / 139
Note: The divisor "139" is the current industry standard for FedEx and UPS Ground/Express. USPS uses a divisor of 166 for certain services.
3. When is Volumetric Weight Used? (Carrier Rules 2026)
It is generally used for air shipments, but more and more carriers now apply it for Ground shipments too.
Here is a summary of how major carriers apply these rules in 2026:
| Carrier | Service Type | Domestic Rules | International Rules | Calculation Base |
|---|---|---|---|---|
| FedEx | Express & Ground | Volumetric Applied | Volumetric Applied | DIM Divisor 139 (US) |
| UPS | Ground & Air | Volumetric Applied | Volumetric Applied | DIM Divisor 139 (US) |
| DHL | Express | Volumetric Applied | Volumetric Applied | Divisor 5000 (Metric) |
| TNT | Economy / Express | Actual Weight (Usually) | Volumetric Applied | Divisor 5000 (Metric) |
| DPD | Road Classic | Actual Weight | Volumetric (Long Dist.) | Cubic meters (m3) |
| USPS | Priority Mail | Zone-Based Rules | Volumetric Applied | Cubic Pricing |
| Road Freight | LTL / FTL | Density Based | Density Based | ~333kg / m3 |
To avoid any inconvenience, we invite you to always consult the general conditions of the carrier you have chosen!
4. How to Reduce Shipping Costs? (Optimization Tips)
Since you pay for empty space, "Shipping Air" is the enemy of your budget.
- Use the Smallest Box Possible: If you pack a phone in a box designed for a TV, you will pay the price of a TV shipment.
- Avoid Over-Boxing: Use adequate packaging that hugs the product (bubble wrap is better than loose peanuts for volume).
- Consolidate: Send several items in one dense package rather than multiple light boxes.
Secursus protects your goods—such as watches, jewelry, art, or second-hand items—regardless of their weight or volume. We offer a flat rate (usually 1%) based on the package value, not the size.
5. FAQ: Dimensional Weight
How to calculate volumetric weight for air freight?
The formula for international air freight often uses a divisor of 6000 or 5000 depending on the forwarder. Always check if your quote says "1:600" or "1:500".
How does USPS calculate cubic pricing?
Cubic pricing is a special tier for small, heavy packages. It is calculated as: (Length x Width x Height) / 1,728. If the result is under 0.50 cubic feet, you qualify for lower rates regardless of weight (up to 20 lbs).
Does Flat Rate shipping go by weight?
No. USPS Flat Rate boxes ignore both actual weight (up to 70 lbs) and volumetric weight. If you ship heavy but small items (like gold or mechanical parts), Flat Rate is often cheaper than standard Priority Mail.
How to calculate volumetric weight for road freight?
Road freight often uses a "Density" standard. A common calculation is 333 kg per cubic meter. You measure the volume in m3 (L x W x H in meters) and multiply by 333 to get the chargeable weight in kg.
