Dimensional weight tells a carrier how much space your cartons occupy. Enter the final packed carton dimensions, quantity and actual weight below to compare express, air-freight and sea-freight measurements before requesting a shipping quote from China.
Use the final outer carton dimensions, including any bulging. The example values represent eight cartons measuring 40 x 50 x 60 cm, each weighing 8 kg.
| Measurement | Formula | Your result |
|---|---|---|
| Actual weight | Actual kg x cartons | 64 kg |
| Express dimensional weight | L x W x H / 5000 | 24 kg/carton |
| Express chargeable weight | Higher of actual or DIM weight | 192 kg total |
| Air-freight dimensional weight | L x W x H / 6000 | 20 kg/carton |
| Air-freight chargeable weight | Higher of actual or DIM weight | 160 kg total |
| Sea-freight volume | L x W x H x cartons / 1,000,000 | 0.96 CBM total |
Planning estimate only. Carrier divisors, rounding rules, minimum charges and route-specific conditions can vary. Confirm the final warehouse measurements and booking quotation before shipping.
What Is Dimensional Weight?
Dimensional weight, also called volumetric weight or DIM weight, converts the space occupied by a carton into a weight value. A large lightweight carton can take more aircraft or delivery-vehicle space than a small dense carton, so carriers compare its dimensional weight with its scale weight.
Chargeable weight = the higher of actual weight or dimensional weightActual Weight vs Dimensional Weight
| Question | Actual weight | Dimensional weight |
|---|---|---|
| What does it measure? | The weight shown on a scale, including packaging. | The shipping space calculated from length, width and height. |
| When does it control the quote? | When the packed goods are dense and heavier than the DIM result. | When the carton is bulky and the DIM result exceeds scale weight. |
| How can you reduce it? | Reduce product or packaging weight without weakening protection. | Reduce unnecessary empty space, carton size or inefficient packing. |
How to Calculate Dimensional Weight in KG
Express courier
For the common planning divisor of 5000:
Length (cm) x Width (cm) x Height (cm) / 5000Air freight
For the common planning divisor of 6000:
Length (cm) x Width (cm) x Height (cm) / 6000LCL sea freight
Sea freight is normally planned by cubic meters rather than a universal dimensional-weight conversion:
Total CBM = Length (cm) x Width (cm) x Height (cm) x Cartons / 1,000,000Minimum billing units and weight-to-measurement rules depend on the forwarder and route, so ask for the complete quotation rather than converting every sea shipment to kilograms.
Worked Example: 40 x 50 x 60 cm, 8 Cartons
Assume each carton weighs 8 kg. The actual total weight is 64 kg.
- Total volume: 40 x 50 x 60 x 8 / 1,000,000 = 0.96 CBM.
- Express DIM weight: 40 x 50 x 60 / 5000 = 24 kg per carton, or 192 kg total.
- Air-freight DIM weight: 40 x 50 x 60 / 6000 = 20 kg per carton, or 160 kg total.
- Chargeable weight: express would be planned at 192 kg and air freight at 160 kg because both exceed the 64 kg actual weight.
The final shipping price still requires the route, destination, product category, carton count and current carrier quotation. A per-kilogram rate alone is not enough.
Common Carton Sizes and DIM Weight
| Carton size | CBM per carton | Express DIM weight (/5000) | Air DIM weight (/6000) |
|---|---|---|---|
| 30 x 20 x 15 cm | 0.009 CBM | 1.8 kg | 1.5 kg |
| 40 x 30 x 25 cm | 0.030 CBM | 6.0 kg | 5.0 kg |
| 50 x 40 x 30 cm | 0.060 CBM | 12.0 kg | 10.0 kg |
| 60 x 40 x 40 cm | 0.096 CBM | 19.2 kg | 16.0 kg |
Why a Freight Quote Changes After Warehouse Measurement
- The production carton is larger than the supplier estimate. Inner packaging, dividers and protective material can increase every side.
- The carton bulges. Carriers may measure the longest outside point, not the printed carton specification.
- The carton quantity changes. Split packing or additional master cartons increases total volume.
- Pallets are added. Pallet height and footprint become part of the shipment measurement.
- The product requires special handling. Batteries, liquids, magnets, oversized items and fragile goods can change the available route and pricing.
This is why buyers should confirm final carton measurements before paying the balance and before booking cargo. Our pre-shipment inspection checklist includes packaging checks that can catch these differences before dispatch.
Five Ways to Reduce Dimensional Weight
- Match the carton to the product. Remove avoidable empty space while keeping enough protection.
- Improve the inner arrangement. Rotate, nest or disassemble products where the design allows it.
- Replace weak outer cartons. A strong correctly sized carton is better than an oversized carton that bulges.
- Consolidate supplier shipments. Repacking several small deliveries at one warehouse can reduce duplicate outer packaging.
- Measure a packed sample carton. Do not rely only on an early spreadsheet estimate from the supplier.
If you are combining goods from multiple factories, see how our China consolidation warehouse service handles collection, carton checks, repacking and one organized shipment. Before dispatch, also verify the shipping marks printed on each carton and understand the information prepared in the shipping manifest.
Frequently Asked Questions
How do I calculate dimensional weight in kg?
Multiply the carton length, width and height in centimeters, then divide by the carrier’s DIM divisor. Compare that result with the actual carton weight and use the higher figure for planning.
Why do some carriers use 5000 and others use 6000?
The divisor reflects the carrier or shipping method’s volume-to-weight rule. Do not assume one divisor applies to every quotation. Confirm it with the carrier or freight forwarder.
Does sea freight use dimensional weight?
LCL sea freight is usually quoted using shipment volume in CBM together with route-specific minimums and weight-to-measurement rules. Calculate the total CBM first and obtain a complete shipping quotation.
Should I use product dimensions or carton dimensions?
Use the final outside dimensions of the packed shipping carton. Product-only dimensions do not include inner protection, retail boxes, master cartons, bulging or pallets.
Not Sure Which Weight Your Shipment Will Be Charged By?
Send us your product photos, final carton size, carton quantity, actual weight and destination country. Our Shenzhen team will review whether repacking, consolidation, express, air freight or sea freight is the practical option before you book.
