A shipment can leave a Chinese factory weighing 50 kg and still appear on a freight quote at a higher billed weight. That gap is chargeable weight, and China air and courier quotes are priced on it rather than on the scale reading.
Freight providers sometimes charge for more than the weight shown on the scale. They also need to consider how much transport space the packed cargo occupies.
This is most familiar with air freight and express courier. However, some Sea Parcel and consolidated freight routes also use weight-to-volume rules when working out the chargeable quantity.
For buyers researching chargeable weight China freight quotes, the key question is not simply, “How heavy are the goods?” You also need to know how large the final packages are and which billing rule applies.
This guide explains how to interpret those figures. If you want to calculate CBM or estimate volumetric weight for your own cartons, use the Prestige Sourcing freight volume calculator.
What does chargeable weight mean?
Chargeable weight is the quantity a freight provider uses to apply its freight rate. Depending on the service, that figure may come from actual weight, package volume or a combination of both.
For air freight and courier, the provider commonly compares actual gross weight with volumetric weight. It then uses the higher figure, subject to its own rounding and minimum-charge rules.
Some consolidated sea services apply a similar principle differently. They may convert weight into a chargeable volume or use another density rule.
The easiest way to understand it: think of a box of feathers
Imagine a very large carton containing just 5 kg of feathers. The scale says 5 kg, but the carton may take up a substantial amount of aircraft space.
Now compare it with a small box containing 5 kg of dense metal parts. Both packages weigh the same. However, the box of feathers could occupy several times more space.
Charging both shipments purely on their 5 kg scale weight would ignore the space the large carton consumes. Volumetric weight gives the carrier a way to account for that difference.
The opposite can also happen. A compact box of very heavy parts may have a low volumetric weight but a high actual weight. In that case, the actual weight will often become the chargeable figure.
Actual weight, volumetric weight and chargeable weight
Actual gross weight
Actual weight is what the finished package weighs on a scale. It includes the product and its final packing materials.
That means the gross weight can include retail boxes, export cartons, protective foam, pallets, crates and wrapping. A product’s net weight is therefore not enough for a final freight quote.
Volumetric weight
Volumetric weight converts the space occupied by a package into an equivalent weight. Providers calculate it from the outside dimensions of the finished package.
The basic metric formula often looks like this:
Length × width × height in centimetres ÷ volumetric divisor
The important part is the divisor. A provider using 5,000 will produce a different volumetric weight from one using 6,000.
Chargeable weight
For many air and courier services, the provider compares actual and volumetric weight. The larger figure becomes the chargeable or billable weight.
Minimum weights, package-level calculations and rounding can then affect the final figure again.
What do the 5,000 and 6,000 divisors mean?
Both figures appear in freight pricing, but you should never assume which one a quote uses.
A divisor of 5,000 generally produces a higher volumetric weight than 6,000. In other words, it prices the same carton as if it were less dense.
For example, consider a carton measuring 60 × 50 × 40 cm.
- Its volume is 120,000 cubic centimetres.
- Using a 5,000 divisor gives a volumetric weight of 24 kg.
- Using a 6,000 divisor gives a volumetric weight of 20 kg.
If our imaginary box of feathers actually weighs 5 kg, neither provider would necessarily bill it at 5 kg. One could treat it as 24 kg, while another could treat it as 20 kg before applying any other service rules.
That is why the divisor matters when comparing two quotes.
5,000 is common with express courier services
Current FedEx New Zealand guidance uses a 5,000 divisor for dimensional weight in centimetres. FedEx also states that it applies dimensional-weight pricing on a per-package basis and rounds package measurements according to its rules.
UPS New Zealand also currently uses a 5,000 divisor for dimensional weight. It compares dimensional weight with actual weight and uses the greater figure as billable weight.
DHL Express also publishes 5,000 as its standard volumetric divisor for dimensions measured in centimetres and weight in kilograms.
6,000 also appears in air cargo
A 6,000 divisor is also used in parts of the air-cargo market. For example, Air New Zealand Cargo’s current domestic cargo guidance calculates volumetric weight by dividing cubic centimetres by 6,000.
That Air New Zealand rule is for its domestic cargo service. It does not mean every China-to-New Zealand air shipment uses 6,000.
In practice, the exact divisor depends on the airline, forwarder, courier product and rate agreement. Therefore, confirm it for the service you are actually buying.
Why two providers can quote different chargeable weights
Two companies can receive exactly the same carton information and still return different chargeable weights.
One provider may use 5,000 while another uses 6,000. They can also have different rounding rules or minimum charges.
Courier providers may calculate each carton separately. Another service may use a shipment-level calculation or apply its own airline tariff rules.
So a cheaper price per kilogram does not automatically mean a cheaper shipment. First confirm how many kilograms the provider intends to charge.
Chargeable weight can apply to some Sea Parcel routes too
Chargeable weight is not limited to aircraft. Some Sea Parcel, DDP and consolidated sea routes also use density-based pricing.
The calculation may look different from an air-freight divisor. Instead of converting centimetres directly into kilograms, the sea service may compare actual CBM with a volume derived from the cargo’s weight.
For example, a particular route might use a rule such as 300 kg = 1 CBM. That is only an illustrative ratio because the actual conversion varies by service.
Assume a shipment physically occupies 0.40 CBM but weighs 180 kg. Under a 300 kg per CBM rule, its weight converts to 0.60 CBM.
The provider may therefore charge 0.60 CBM rather than the shipment’s physical 0.40 CBM. In this case, the cargo is being penalised for density rather than for being light and bulky.
Other Sea Parcel routes may use a different ratio, a minimum CBM, a minimum shipment charge or another pricing method entirely.
So, before accepting a Sea Parcel quote, ask whether the provider is billing on actual volume, weight, chargeable volume or a route-specific minimum.
Why the weight can change after the factory finishes packing
The supplier originally used estimated dimensions
Factories often provide approximate carton details while production is still underway. Those figures are useful for budgeting, but they should not become the final booking measurements.
Once the factory packs the goods, ask for the outside dimensions and gross weight of every package.
The supplier gave product dimensions instead of carton dimensions
A factory may quote the size of the product or retail box. Freight providers need the outside dimensions of the export carton, crate or pallet.
Protective foam, dividers and outer packaging can make the shipping package considerably larger.
The warehouse repacked the cargo
A weak export carton may need replacement. The warehouse might also add protection, combine packages or place the goods on a pallet.
These changes can increase both the scale weight and the outside dimensions.
The carrier reweighed or remeasured it
The original freight quote may rely on figures supplied by the factory. Later, a carrier or warehouse can verify the shipment itself.
If those measurements differ, the final chargeable weight can change. This is one reason accurate factory packing data matters before booking.
Why calculating only the total shipment can give the wrong answer
Another common mistake is to calculate the total shipment volume and assume the carrier will use the same figure.
Some courier services assess each carton separately. A shipment can therefore contain one carton that bills on actual weight and another that bills on volumetric weight.
The provider may also round each package before adding the figures together. That can produce a different total from a calculation based only on overall CBM.
If a billed weight looks unusual, ask for the package-level calculation rather than trying to work backwards from the final invoice.
How to check a chargeable weight China quote
Ask the provider to show the billing basis, not just the freight rate.
- Confirm the final number of cartons, crates or pallets.
- Use the outside dimensions after packing.
- Use gross weight rather than product net weight.
- Ask which volumetric divisor or density ratio applies.
- Confirm how dimensions and weight are rounded.
- Check whether each package is calculated separately.
- Ask about minimum chargeable weights or volumes.
- Confirm whether pallet dimensions are included.
- Ask whether the carrier can remeasure the cargo after booking.
These details make it much easier to compare quotes on the same basis. Our guide to China to NZ freight quote information and excluded costs covers the other information you should provide before relying on a freight price.
Do not reduce carton size at the expense of protection
A large amount of unused space can increase volumetric weight unnecessarily. Therefore, right-sizing the carton can reduce freight costs.
However, do not tell a factory simply to use the smallest possible box. International freight involves repeated handling, stacking and warehouse movement.
The better approach is to remove unnecessary empty space while keeping enough protection for the product. Our guide to export-quality cartons from China explains export carton strength and packing considerations in more detail.
What this means for New Zealand importers
Chargeable weight determines freight pricing. It does not determine the Customs value of the product itself.
However, freight cost can still affect the final landed cost in New Zealand. New Zealand Customs currently calculates import GST, where Customs collects it, on the value of the goods plus applicable duty, international freight or courier costs, and insurance.
You can review the current rules on the New Zealand Customs duty and GST page.
For early budgeting, the Prestige Sourcing New Zealand Customs fee calculator can also help estimate relevant GST, duty and border levies.
Get the final packed figures before booking
The factory’s scale weight is only one part of the freight calculation. Carton size, density, the service’s divisor, minimum charges and rounding rules can all change what you actually pay.
Start with the final packed measurements. Then ask the provider to confirm the billing rule before comparing rates.
Prestige Sourcing’s China to New Zealand Air Freight service can help review packed shipment information, clarify the chargeable weight used for the quoted service and coordinate the agreed China-to-New Zealand freight process.
If your factory has finished packing, provide the carton count, outside dimensions, gross weight, product details and New Zealand destination. That gives you a much stronger basis for checking the final freight quote before the goods leave China.
Frequently asked questions
Why can a 5 kg carton be charged as 20 kg or more?
The carton may be large relative to its physical weight. A provider can calculate volumetric weight from its dimensions and use that higher figure for billing.
What is the difference between a 5,000 and 6,000 divisor?
A 5,000 divisor produces a higher volumetric weight for the same carton. Both divisors appear in freight pricing, so always confirm which one applies to the quoted service.
Does chargeable weight apply only to air freight?
No. Air freight and courier commonly use volumetric weight, but some Sea Parcel and consolidated sea routes also use density or weight-to-volume rules.
Does every Sea Parcel service use the same conversion?
No. Some routes use a weight-to-CBM ratio, while others have minimum volumes or different charging structures. Check the specific service before booking.
Can I use the dimensions on my supplier’s product listing?
Not for a final freight quote. Use the outside measurements and gross weight of the finished export cartons after packing.
