Carriers charge based on whichever is greater: actual weight or volumetric weight (also called cubic weight or dimensional weight). This prevents carriers from losing money on large but lightweight packages.

The Formula

Volumetric weight is calculated as:

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

Common Divisors by Carrier

Australia Post (domestic): 5000
DHL, FedEx, UPS (international): 5000
Aramex: 5000
Some freight carriers: 4000 or 6000

Always check with your specific carrier for their divisor as it may vary by service level.

Worked Example

Package dimensions: 40 cm × 30 cm × 20 cm

Calculate volume: 40 × 30 × 20 = 24,000 cm³
Divide by carrier divisor (5000): 24,000 ÷ 5000 = 4.8 kg

If your package actually weighs 2 kg, you'll be charged for 4.8 kg (the volumetric weight) because it's higher.

Another Example

Package dimensions: 50 cm × 40 cm × 30 cm

Calculate volume: 50 × 40 × 30 = 60,000 cm³
Divide by 5000: 60,000 ÷ 5000 = 12 kg

Why This Matters

Many e-commerce businesses lose money because they don't account for volumetric weight when quoting shipping at checkout. Pack to the Future's Cubic Weight Generator automatically applies carrier-specific rules so you always get accurate quotes.

How Pack to the Future Helps

Automatic calculation: We apply each carrier's divisor automatically
Product AI: Estimates dimensions so you don't have to measure every SKU
Rate comparison: Shows each carrier's rate, based on actual OR volumetric weight, so you can compare accurately