How to Calculate Chargeable Weight for Air Freight

Why Your 5kg Box Might Be Charged as 15kg

Air freight pricing has a catch that surprises many importers: carriers don't just charge based on how heavy your package is. They also calculate a theoretical weight based on the package's volume — and charge you whichever is higher.

This is because aircraft have limited space. A large, lightweight package takes up valuable cargo space that could be used for denser goods.

The Two Weights

Actual Weight (Gross Weight)

Simply weigh the package on a scale. Include the product, packaging materials, and the carton itself.

Volumetric Weight (Dimensional Weight)

Calculated from the package dimensions:

Volumetric weight (kg) = (Length × Width × Height in cm) ÷ Divisor

The divisor varies by carrier:

• Standard air freight: 6,000
• IATA standard: 5,000
• Express couriers (DHL, FedEx, UPS): 5,000
• Sea freight: 1,000 (rarely used, but good to know)

Chargeable Weight

Chargeable weight = whichever is higher (actual or volumetric)

Use the calculator below to compare both and see which applies to your shipment.

Worked Example

A carton measuring 50cm × 40cm × 30cm, weighing 8kg:

Volumetric weight = (50 × 40 × 30) ÷ 6,000 = 10.0 kg

Actual weight = 8.0 kg

Chargeable weight = 10.0 kg (volumetric is higher)

You'll be charged for 10kg even though the box only weighs 8kg. At $5/kg, that's $50 instead of $40 — a 25% increase.

When Volumetric Weight Hits Hardest

Products that are light relative to their size get hit hardest:

How to Reduce Your Chargeable Weight

1. Reduce Packaging Dimensions

Even small reductions matter. Cutting 5cm from each dimension of a 50×40×30cm box:

• Before: (50 × 40 × 30) ÷ 6,000 = 10.0 kg volumetric
• After: (45 × 35 × 25) ÷ 6,000 = 6.6 kg volumetric

That's a 34% reduction in chargeable weight.

2. Remove Excess Void Fill

Ask your supplier to pack products snugly. Excessive padding increases dimensions without adding protection if the product doesn't need it.

3. Use Vacuum Packaging

For soft goods (clothing, textiles, bedding), vacuum packaging can dramatically reduce volume.

4. Consider Flat-Pack

Products that can be shipped disassembled take less space. You'll need to handle assembly, but the freight savings can be substantial.

5. Switch to Sea Freight

If your product is consistently charged on volumetric weight, sea freight may be dramatically cheaper. Compare shipping modes to see the cost difference.

Chargeable Weight for Multiple Packages

When shipping multiple packages, some carriers:

• Calculate chargeable weight per package (and sum them)
• Calculate based on total shipment weight and total dimensions

The per-package method is more common. Always clarify with your carrier.

Express Courier vs Air Freight

Express couriers use a lower divisor, meaning volumetric weight is higher. For volume-sensitive products, standard air freight is cheaper than courier.

The Sea Freight Alternative

Sea freight uses a divisor of 1,000, making volumetric weight much less of an issue. For most products, actual weight determines the cost. If your air freight bill is dominated by volumetric charges, sea freight can reduce shipping costs by 70–90%.

Use LandedCost.io to compare air and sea freight costs for your products and see the impact on your landed cost.