Australia

Australia Post dimensional weight

Australia Post uses a divisor of 4000 cm³/kg — notably more aggressive than the 5000 used by most carriers globally. This means lightweight bulky packages will bill at higher DIM weight on Australia Post than on most international competitors.

Metric only
Imperial divisor
4000
Metric divisor
No minimum
DIM applies
Calculate for aus_post
CALC.001 / DIM-WEIGHT
Unit system
Package dimensions
L
W
H
Actual weight (lb)
ƒ

Awaiting dimensions. Enter package details to compute billable weight.

Service tiers

Australia Post divisors by service

Service Imperial (in/lb) Metric (cm/kg) Notes
Parcel Post (domestic) 4000 All packages
Express Post (domestic) 4000 All packages
International Standard 4000 All packages
International Express 4000 All packages
When to use

Best for, avoid when

— 01 · BEST FOR

When Australia Post wins

Domestic Australian shipments, AU-NZ and AU-Asia lanes

— 02 · AVOID WHEN

When to look elsewhere

Lightweight bulky goods (4000 divisor hits hard)

— 03 · OFFICIAL RATES

Get a live quote

Run an actual rate quote on Australia Post's official site to confirm pricing and check current surcharges.

Visit Australia Post ↗

Common questions

Australia Post DIM weight — FAQ

What is Australia Post's dimensional weight divisor?

Australia Post uses a divisor of 4000 cm³/kg (metric) — this carrier publishes only metric divisors. The DIM weight formula is volume divided by this number, rounded up to the nearest whole pound or kilogram.

When does Australia Post apply DIM weight?

Australia Post applies dimensional weight to packages above No minimum. The billable weight is always the greater of the actual weight or the calculated DIM weight.

How do I reduce Australia Post DIM charges?

Use right-sized packaging — every cubic inch you save is divided by the divisor and removed from your billable weight. Avoid excessive void fill and consider custom box sizes for products you ship frequently. For occasional shippers, use the calculator above to test packaging changes before you commit to new materials.