How to Calculate Volumetric Weight of a Box

Accurately determine the chargeable weight of your shipments using our professional volumetric weight calculator. Understand the formula, compare carriers, and optimize your shipping costs.

Volumetric Weight Calculator

Enter package dimensions and weight to find the chargeable weight.

Figure 1: Comparison of Actual Weight vs. Volumetric Weight. The higher value is the Chargeable Weight.

Metric	Value	Calculation / Note
Dimensions	–	Input Values
Volume	–	L × W × H
DIM Factor	–	Carrier Standard
Volumetric Weight	–	Volume ÷ Factor

Table 1: Detailed breakdown of the volumetric weight calculation.

What is Volumetric Weight?

Volumetric weight (also known as dimensional weight or DIM weight) is a pricing technique used by commercial freight transport and postal companies. It reflects the density of a package, which is the amount of space a package occupies in relation to its actual weight.

When you learn how to calculate volumetric weight of a box, you are essentially determining the "theoretical" weight of the package based on its size. Carriers compare this volumetric weight against the actual scale weight of the package and charge based on whichever is greater. This ensures that lightweight but bulky items (like pillows or bubble wrap) are charged fairly for the space they consume in a truck or aircraft.

This concept is critical for e-commerce businesses, logistics managers, and anyone shipping packages internationally or domestically. Ignoring volumetric weight can lead to unexpected shipping costs and budget overruns.

How to Calculate Volumetric Weight of a Box: The Formula

The formula for calculating volumetric weight is standardized across the logistics industry, though the specific "divisor" (DIM factor) may vary by carrier (e.g., DHL, FedEx, UPS) and service type (Air vs. Road).

Formula:
Volumetric Weight = (Length × Width × Height) / DIM Factor

Variable Definitions

Variable	Meaning	Common Units	Typical Range
Length (L)	Longest side of the box	cm or inches	10 – 200+
Width (W)	Second longest side	cm or inches	10 – 150+
Height (H)	Shortest side	cm or inches	5 – 150+
DIM Factor	Divisor set by carrier	N/A	5000, 6000, 139, 166

Table 2: Key variables used in the volumetric weight formula.

Practical Examples (Real-World Use Cases)

Example 1: International Air Freight (Metric)

A company is shipping a box of electronic components.

• Dimensions: 50 cm x 40 cm x 30 cm
• Actual Weight: 8 kg
• Carrier Divisor: 5000 (Standard for Air Freight)

Calculation:
1. Volume = 50 × 40 × 30 = 60,000 cm³
2. Volumetric Weight = 60,000 / 5000 = 12 kg

Result: Since 12 kg (Volumetric) > 8 kg (Actual), the Chargeable Weight is 12 kg. The shipper pays for 12 kg.

Example 2: Domestic Ground Shipping (Imperial)

A retailer ships a large stuffed animal.

• Dimensions: 20 in x 20 in x 20 in
• Actual Weight: 5 lbs
• Carrier Divisor: 139 (Common for UPS/FedEx)

Calculation:
1. Volume = 20 × 20 × 20 = 8,000 in³
2. Volumetric Weight = 8,000 / 139 ≈ 57.55 lbs

Result: The carrier will round up to 58 lbs. Since 58 lbs > 5 lbs, the Chargeable Weight is 58 lbs. This highlights how light, bulky items can be very expensive to ship.

How to Use This Volumetric Weight Calculator

1. Select Unit System: Choose between Metric (cm/kg) or Imperial (in/lb) based on your location and carrier.
2. Enter Dimensions: Measure the length, width, and height of your package. Always measure the outermost points, including bulges or tape.
3. Enter Actual Weight: Weigh the package on a scale and input the value.
4. Select DIM Factor: Choose the divisor used by your carrier.
   • Use 5000 for most international air couriers (DHL, FedEx Int'l).
   • Use 139 for UPS/FedEx domestic (USA).
   • Use 6000 for some ground freight or older standards.
5. Analyze Results: The calculator will instantly show the Volumetric Weight and highlight the Chargeable Weight.

Key Factors That Affect Volumetric Weight Results

Understanding the variables that influence how to calculate volumetric weight of a box can help you save money.

1. The DIM Factor (Divisor)

The divisor is the most critical constant. A lower divisor (e.g., 139 vs 166) results in a higher volumetric weight, increasing costs. Carriers adjust this annually to manage capacity.

2. Packaging Efficiency

Excessive packaging materials or using a box that is too large for the item drastically increases volume without adding actual weight. Optimizing box size is the best way to reduce volumetric weight.

3. Measurement Rounding

Carriers typically round dimensions to the nearest whole number (cm or inch) before calculating. A 10.2 cm box might be treated as 11 cm, slightly increasing the billable weight.

4. Palletization

If you ship on pallets, the dimensions of the pallet itself (and the empty space between boxes) contribute to the total volumetric weight of the shipment.

5. Carrier Service Type

Express services often use more aggressive divisors (e.g., 5000) compared to economy or sea freight services (which might use 6000 or calculate per cubic meter).

6. Irregular Shapes

For cylinders or non-rectangular items, carriers calculate volume based on the smallest rectangular box that would enclose the item. This "squaring the circle" adds phantom volume to your cost.

Frequently Asked Questions (FAQ)

Why is my chargeable weight higher than the actual weight?

This happens when your package is low density—large in size but light in weight. Carriers charge for the space occupied in the vehicle, not just the physical weight.

What is the standard divisor for air freight?

The industry standard for international air couriers (like DHL, FedEx, UPS) is typically 5000 cm³/kg. However, always check your specific contract.

Does volumetric weight apply to sea freight?

Yes, but the calculation is different. Sea freight (LCL) is usually charged per Cubic Meter (CBM) or per Tonne, with a ratio of 1 CBM = 1000 kg.

How can I reduce volumetric weight?

Use the smallest possible box for your item, minimize void fill (packing peanuts), and consider vacuum sealing soft items like clothing.

Do I measure the inside or outside of the box?

Always measure the outside dimensions. Carriers measure the external space the package consumes.

What is the difference between taxable weight and chargeable weight?

In shipping, "chargeable weight" is the final weight used to calculate the invoice price. It is the higher of the actual or volumetric weight.

Is the divisor 139 or 166 for UPS?

Currently, UPS and FedEx use 139 for most commercial and residential packages in the US. The 166 divisor is largely obsolete for major carriers but may exist in specific contracts.

Can I negotiate the DIM factor?

Yes. High-volume shippers can often negotiate a higher divisor (e.g., moving from 139 to 166), which effectively lowers shipping costs for lightweight items.