How do I calculate chargeable weight?

Multiply the length, width, and height in centimetres, then divide by the carrier's divisor, usually 5,000 for air. Compare that volumetric weight with the actual weight and use the larger of the two. That figure is the chargeable weight the freight cost is based on.

Which divisor should I use?

Air freight and couriers commonly use 5,000, road freight often uses 4,000, and sea freight is usually charged by cubic metre instead. Check your carrier's terms, then enter the right divisor here. The default of 5,000 suits most courier parcels.

Freight Calculator

This calculator works out what a parcel is likely to cost to send by finding its chargeable weight, the figure couriers and freight companies actually bill on. Carriers do not price purely on how heavy a box is; a large, light parcel still takes up space in a truck or plane, so they compare the actual weight against a volumetric weight worked out from the box's size, then charge on whichever is greater. You enter the parcel's length, width and height in centimetres, its actual weight in kilograms, the divisor your carrier uses (5,000 suits most air and courier services, though road freight often uses 4,000), and the rate you have been quoted per kilogram. The calculator returns the volumetric weight, the chargeable weight, and an estimated freight cost based on that rate, updating instantly as you change any field. This makes it easy to test different box sizes or carriers and see how much a bulky but light parcel can cost compared with its actual weight. Use it to sanity-check a courier quote, compare packaging or carrier options before you ship, or budget for freight when importing or sending goods around New Zealand or overseas. Treat the result as an estimate only, since carriers commonly add fuel surcharges, rural delivery fees and minimum charges on top of the base freight cost calculated here.

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Length (cm)

Width (cm)

Height (cm)

Actual weight (kg)

Divisor

Rate per kg

estimated freight cost

Volumetric weight0 kg

Chargeable weight0 kg

Estimate only. Carriers add fuel surcharges, rural delivery, and minimum charges.

How freight is priced

Carriers cannot just charge by weight, because a large box of pillows would travel almost free while taking up a whole pallet. Instead they work out a volumetric weight from the size of the parcel and charge on whichever is greater, the actual weight or the volumetric weight. That is the chargeable weight.

Worked example

A 40 by 30 by 25 cm box is 30,000 cubic centimetres. Divided by 5,000, the volumetric weight is 6 kg. If the parcel actually weighs 4 kg, the chargeable weight is 6 kg. At $3.50 per kg, the freight estimate is $21.

The formulas

Volumetric weight = length times width times height, divided by the divisor
Chargeable weight = the greater of actual and volumetric weight
Cost = chargeable weight times rate per kg

Related calculators

Import Duty Calculator: duty and GST on imports.
Cubic Metre Calculator: volume of a shipment.
Currency Converter: convert an overseas freight quote.
Moving Costs Calculator: cost of a household move.

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