If your air freight quote feels “too expensive for the weight,” you’re probably being billed on space, not kilograms. Air cargo pricing is driven by chargeable weight, which is usually the higher of actual weight and volumetric weight.

If you want the full context (airports, documents, common delays, and cost drivers), read the complete air freight guide for Australia . This page focuses on one thing only: how chargeable weight is calculated, why it inflates your bill, and what to change so you stop overpaying.

What chargeable weight means

Chargeable weight is the “billable weight” used to price air cargo. Aircraft have two hard limits:

• Weight (how heavy the load is)
• Volume (how much space the load consumes)

So the billable number is typically: chargeable weight = the higher of actual weight or volumetric weight.

Actual weight vs volumetric weight

Actual weight

The scale weight of the shipment (gross weight), in kilograms.

Volumetric weight

A calculated weight that represents space usage.

A common formula is:

Volumetric weight (kg) = (L × W × H in cm) ÷ 6000

Some carriers use a different divisor depending on service level or network rules, but 6000 is a common baseline.

Fast examples (so you can spot the trap)

Example 1: Light but bulky carton

• Dimensions: 60 × 50 × 40 cm
• Actual weight: 10 kg
• Volumetric weight: (60×50×40) ÷ 6000 = 20 kg
• Chargeable weight: 20 kg

You pay as if it weighs 20 kg.

Example 2: Heavy but compact carton

• Dimensions: 40 × 30 × 30 cm
• Actual weight: 25 kg
• Volumetric weight: (40×30×30) ÷ 6000 = 6 kg
• Chargeable weight: 25 kg

You pay on actual weight.

Why air freight quotes jump after pickup

These are the common causes of “quote shock”:

• Cartons are bigger than the dimensions given at booking
• Excess void space (“air in the box”)
• One awkward carton breaks stacking efficiency and inflates billed volume
• Weak cartons become non-stackable (wastes space and changes handling)
• Pallet builds add height and footprint without reducing total cubic volume
• Pieces are oversize or irregular and trigger special handling

The most common mistakes

1) Measuring the product, not the packed carton

Pricing follows the final packed dimensions. Always measure after packing.

2) Treating all cartons as “close enough”

Small differences multiplied across many cartons create big billable volume.

3) Random carton sizes

Mixed carton footprints waste pallet space and increase total cubic volume.

4) Overprotecting durable goods

Over-padding fragile goods is smart. Over-padding sturdy goods is expensive.

5) Assuming palletising always saves money

Pallets can reduce handling risk, but they can also increase chargeable weight if the build is tall or inefficient.

How to reduce chargeable weight without increasing damage risk

The goal is not “smaller at all costs.” The goal is right-sized packaging with real protection.

Packaging changes that usually work

• Standardise carton sizes (fewer footprints, consistent shapes)
• Reduce void space (tighter internal packing, correct box size)
• Use stronger cartons so they can be stacked safely
• Avoid tall “tower cartons” that waste space around them
• Use corner protection and tight wrap instead of oversized outer boxes
• Design packaging to fit standard pallet footprints when volume is repeatable

Planning changes that usually work

• Consolidate cartons onto pallets only when it reduces total cubic volume
• Avoid one-off oversize pieces where possible
• Confirm dimensions and weights before booking (not after pickup)
• Maintain a simple SKU sheet: carton size, weight, pieces per pallet, photos

Pallets: when they help and when they hurt

Pallets help when:

• Cartons stack cleanly and fill the footprint efficiently
• Total cubic volume is lower than loose cartons
• Handling is faster and damage risk is reduced

Pallets hurt when:

• The pallet footprint is much larger than the cartons
• The build adds height without improving protection
• The pallet is unstable and requires rework, strapping, or extra space

Practical checklist before you book

• Confirm the carrier’s volumetric divisor (6000 is common, not universal)
• Measure final packed dimensions (not product dimensions)
• Record total pieces, dimensions, and actual weight
• Identify any oversize or non-stackable pieces early
• Decide if palletising reduces total volume or simply adds height
• Use cartons strong enough for stacking and handling
• Keep photos of packing and pallet builds for repeat shipments

Reference table

Summary

Air freight pricing is not “per kilogram.” It’s per kilogram or per space, whichever is higher. If you understand chargeable weight, measure accurately, and tighten packaging without weakening protection, you can reduce costs immediately and avoid surprises at the terminal.