Cubic Weight Calculator
Australian standard 250 kg/m³ (AusPost, StarTrack, Toll) — billable weight as you type.
Australian carriers charge parcels on cubic weight when it exceeds the actual weight. The formula: L × W × H (metres) × 250 = cubic weight in kg. Working in centimetres, that is identical to L × W × H (cm) ÷ 4,000 — this calculator uses the exact same math.
Example: a 60 × 40 × 40 cm carton weighing 8 kg → 0.6 × 0.4 × 0.4 × 250 = 24 kg cubic weight. You are billed for 24 kg, three times the scale weight. That gap is why right-sized packaging matters more in Australia than almost anywhere else — the 250 kg/m³ factor is stricter than the international express standard (200 kg/m³, i.e. ÷5,000).
Shipping internationally instead? Use the volumetric weight calculator (÷5,000 for DHL/UPS/FedEx) or the air freight calculator (IATA ÷6,000).
How do I calculate cubic weight?+
Multiply length × width × height in metres, then multiply by the cubic conversion factor — 250 kg per cubic metre for most Australian carriers. A 40 × 30 × 30 cm carton: 0.4 × 0.3 × 0.3 × 250 = 9 kg cubic weight. In centimetres this is the same as L × W × H ÷ 4,000.
What cubic factor do Australia Post, StarTrack and Toll use?+
Australia Post (including eParcel contracts) and StarTrack use 250 kg/m³. Toll and most other Australian domestic carriers also use 250 kg/m³, though some services and contracts vary — check your rate card.
Do I get charged actual weight or cubic weight?+
Whichever is greater. If your parcel weighs 10 kg but its cubic weight is 15 kg, you pay for 15 kg. Dense parcels are billed on the scale; bulky parcels on volume.
Is cubic weight the same as volumetric or dimensional weight?+
Yes — cubic weight is the Australian/New Zealand term for volumetric (dimensional) weight. International couriers like DHL/FedEx/UPS express the same idea as a divisor: ÷5,000 cm³/kg internationally, which equals 200 kg/m³.
How can I reduce cubic weight charges?+
Use the smallest box that protects the item, compress soft goods, and avoid oversized packaging — at 250 kg/m³, every extra centimetre of box size costs real money on light items.