CBM and chargeable weight calculator
CBM (cubic metres) is length × width × height in metres, multiplied by the number of pieces. LCL sea freight is charged on whichever is greater: the volume in CBM or the weight in tonnes, where 1 CBM counts as 1,000 kg (W/M). Enter each package size below to get the total volume, the chargeable basis and an approximate container suggestion.
Your results
Enter the length, width and height of at least one package to see the total volume.
How do you calculate CBM?
Multiply length × width × height in metres, then multiply by the number of identical pieces.
- From centimetres:
L × W × H ÷ 1,000,000 - From inches:
L × W × H ÷ 61,024(1 m³ ≈ 61,024 in³)
Example: 20 cartons of 60 × 40 × 50 cm → 0.6 × 0.4 × 0.5 = 0.12 m³ per carton → 2.4 CBM in total.
Measure the outside of the packed carton or pallet at its widest point, including the pallet base. Round up rather than down: the warehouse re-measures the cargo when it is received, and that figure is the one that appears on the invoice.
What is chargeable weight in sea freight (W/M)?
For LCL and break-bulk cargo, ocean freight is charged per revenue tonne, also written W/M (weight or measurement). Each 1 CBM is compared with 1,000 kg and you pay for whichever is greater.
| Shipment | Volume | Weight | Chargeable |
|---|---|---|---|
| Light cargo (e.g. furniture) | 6 CBM | 1,800 kg | 6 W/M (by volume) |
| Dense cargo (e.g. ceramic tiles) | 3 CBM | 7,500 kg | 7.5 W/M (by weight) |
FCL is priced per container, not per CBM. W/M matters for LCL freight and for destination charges that are billed per W/M, such as CFS handling and warehouse storage.
How is air volumetric weight calculated?
Airlines charge the greater of the actual weight and the volumetric weight. The usual IATA divisor is 6,000 cm³ per kg, which means 1 CBM counts as about 167 kg:
L × W × H (cm) ÷ 6,000 = volumetric kg
Example: a box of 100 × 80 × 60 cm → 480,000 ÷ 6,000 = 80 kg volumetric. If the box weighs 45 kg, the airline charges 80 kg. Express couriers often use a divisor of 5,000, which makes the same box 96 kg. The calculator shows the air figure for comparison; the divisor that applies to your shipment is stated in the quote.
Which container will my cargo fit in?
Containers are rarely filled to their full cubic capacity, because cartons do not stack perfectly and loads need bracing. For planning we use these approximate usable volumes:
| Container | Internal capacity | Usable in practice |
|---|---|---|
| 20′ Standard (20GP) | ≈ 33 m³ | ≈ 25–28 m³ |
| 40′ Standard (40GP) | ≈ 67 m³ | ≈ 55–58 m³ |
| 40′ High Cube (40HC) | ≈ 76 m³ | ≈ 65–68 m³ |
Weight can be the limit before volume. A 20′ container is rated for roughly 28 tonnes of cargo, but road weight limits at origin or destination are often lower, and dense cargo such as tiles, steel or paper fills a 20′ by weight long before it is full by volume. Below roughly 15 CBM, LCL is often cheaper than a 20′ FCL, so compare both quotes.
Frequently asked questions
How many CBM fit in a 20ft container?
A 20′ standard container has about 33 m³ of internal space, but in practice you can load about 25–28 CBM of cartons. For planning we use 28 CBM; the real figure depends on carton sizes, pallets and stacking limits.
Is 1 CBM equal to 1,000 kg?
Only for charging purposes in sea freight. Under the W/M rule, 1 CBM is treated as equal to 1,000 kg (one revenue tonne) and you pay on whichever figure is greater. It says nothing about the actual weight of your cargo.
Should I measure with or without the pallet?
With the pallet. Carriers and warehouses measure the full outside dimensions of each handling unit, including the pallet base and any overhang, so include them to avoid a higher invoice later.
When is LCL cheaper than FCL?
As a rough guide, LCL is usually cheaper than a 20′ FCL below about 15 CBM, and FCL tends to win above that. Destination LCL charges (CFS handling, delivery order, unpacking) can change the result, so compare two itemised quotes before deciding.
Is the calculator result what I will be charged?
No. It is an estimate for planning. The carrier or warehouse measures the cargo on receipt, and that measurement is what appears on the invoice. Your quote states the basis used for each charge.
Next step
Know your CBM? Get an itemised quote
Send the volume, weight and route. A coordinator compares LCL and FCL options and replies with an itemised quote.
- One named coordinator on WhatsApp
- Itemised quote, no changes without your approval
- Replies in English, Arabic or Persian