1. What Is CBM?
CBM means cubic metre (m³). It tells a shipping company how much room your cartons occupy. One carton measuring 100 × 100 × 100 cm occupies exactly 1 CBM, whether it contains textiles, toys or metal parts.
For different carton sizes, calculate each carton group separately and add the CBM. Measure outer packed-carton dimensions, not the product dimensions before packaging.
2. Three Common Charging Rules
Standard Air Freight
≈ 167 kg / CBMCommon 6,000 divisor. Compare volumetric weight and actual gross weight; usually charge the higher.
Sea Freight — Toppingdom Route Reference
750 kg / CBMFor the currently published Foshan → Kano calculator route, compare measured CBM with gross weight ÷ 750. This is route-specific.
Express Courier
200 kg / CBMDHL Express commonly applies a 5,000 divisor. The courier's actual service terms and package rounding apply.
3. Why Does Air Freight Use 167 kg per CBM?
Many general air-cargo services use a volumetric divisor of 6,000 cubic centimetres per kg, described in IATA air-cargo programme material. This converts space into a weight-equivalent used for pricing.
One cubic metre is 1,000,000 cubic centimetres. Therefore 1,000,000 ÷ 6,000 = 166.67 kg (often expressed as 167 kg). If a shipment is 1 CBM and its scale weight is 80 kg, the 6,000-divisor volumetric weight is about 166.67 kg, so the carrier may charge around 167 kg according to its rounding rules.
Important: Not every air product uses the same divisor or rounding method. Confirm the actual airline or freight-forwarder contract before quoting a customer.
4. Why Does DHL Express Use About 200 kg per CBM?
DHL Express commonly applies a divisor of 5,000 rather than 6,000, which gives 1,000,000 ÷ 5,000 = 200 kg for 1 CBM. The billable amount generally compares the courier's volumetric weight with actual gross weight. Other courier products may have different rules.
5. Sea Freight Is Different: W/M and Route-Specific Rules
Less-than-container-load (LCL) sea freight is often billed by W/M (weight or measurement), also called revenue tons (RT). A common comparison is 1 CBM versus 1 metric ton (1,000 kg), with the higher chargeable number used.
But Toppingdom's published Foshan → Kano planning route is configured at 750 kg/CBM, not 1,000 kg/CBM. For that route's calculator:
This is the commercial configuration used for our displayed reference route—not a universal sea-freight rule. Other carriers or routes may use the 1,000 kg/RT benchmark or different minimum charges. A written route-specific quotation always takes priority.
Example of heavy cargo: A dense 1 CBM consignment weighing 900 kg gives 900 ÷ 750 = 1.20 chargeable CBM on our published reference. Using a 1,000 kg/RT W/M comparison instead would give 1.00 RT. That is why the same shipment can receive different quotes from different carriers.
6. Real Calculation: 1 CBM and 80 kg
Imagine goods shipped from China to Nigeria in packed cartons totalling 1.00 CBM, with a combined actual gross weight of 80 kg:
| Shipping method | Weight or volume comparison | Chargeable basis |
|---|---|---|
| Air freight (÷ 6,000) | Actual 80 kg vs volumetric 166.67 kg | About 167 kg, subject to rounding |
| Sea freight (Toppingdom 750 kg/CBM reference) | Measured 1 CBM vs 80 ÷ 750 = 0.107 CBM | 1.00 chargeable CBM |
| Express courier (÷ 5,000) | Actual 80 kg vs volumetric 200 kg | 200 kg, subject to courier rules |
These figures are not freight prices. To estimate a price, multiply the chargeable basis by the applicable rate for that shipping mode and cargo category, then consider any separate charges or exclusions.
7. Why Is My Final Shipping Quote Different From a Website Estimate?
The final cost can be affected by the product type, branded goods, built-in batteries, liquids or other special handling, the warehouse-confirmed packaging, shipping route, chargeable weight, exchange rates, customs or clearance arrangements and delivery to your specific address in Nigeria.
A web calculator is for early budgeting. It is not a guaranteed final invoice. Customs clearance, China local transport, consolidation, insurance, inspection, port or warehouse handling, and Nigeria inland delivery may be included, excluded or charged separately depending on the written quotation.
8. What Information Should You Send Before Asking for a Quote?
- Product link or clear product name/photo and description
- Quantity, number of cartons and any brand/battery/liquid details
- Outer length, width and height for each packed-carton size
- Total actual gross weight including packaging
- Supplier city or collection address in China and estimated cargo value
- Preferred shipping method plus Nigerian delivery city and full final address if door delivery is needed
If your supplier has not supplied final measurements, ask them for the packed carton dimensions and gross weight. Toppingdom can check the warehouse measurements after receiving the goods, subject to the agreed service scope.
Frequently Asked Questions
Does 1 CBM always equal 167 kg?
No. 167 kg is an approximate air-freight volumetric equivalent when the carrier uses a 6,000 divisor. The shipment could physically weigh 20 kg, 80 kg or 300 kg.
Why does Toppingdom show 750 kg/CBM when others say 1,000 kg?
The calculator reflects our published Foshan-to-Kano route reference. Many LCL carriers use 1,000 kg per revenue ton; a different carrier or trade lane can have different commercial terms. Follow your confirmed written route quote.
Is clearance and Nigerian delivery included?
Not automatically. The calculator can show a separate route clearance reference. Nigeria inland delivery, services and special charges must be clearly included or excluded in the quotation.
Can I ship goods I bought myself from 1688?
Yes, you may request receiving, consolidation and shipping coordination even when you purchased from your own supplier. Please send the product and supplier information.
Can I get an exact quote without knowing CBM or weight?
We may offer a preliminary estimate, but a confirmed quote needs sufficiently reliable measurements and cargo details. Supplier estimates may change after actual warehouse measurement.
Official References and Further Reading
- IATA — European Air Cargo Programme Handbook, Volume Weight section (6,000 divisor in the programme).
- DHL Global Forwarding — Calculating Chargeable Weight by Air and Ocean.
- DHL Express — How to Calculate Volumetric Weight (5,000 divisor).
Carrier rules and commercial rates may change. Verify the shipping product, route, minimums and rounding applied to your shipment.
Related guides: Shipping Cost from China to Nigeria · Our Shipping Services · All Buying Guides.