CBM calculator
CBM is length × width × height in metres × the number of cartons. 50 cartons of 40 × 30 × 20 cm are 1.2 m³ (42.38 ft³), about 3.6 % of a 20GP. Add more carton sizes for a mixed shipment and see the air and LCL chargeable figures.
Link a result: ?l=40&w=30&h=20&qty=50&wt=12 or ?rows=40x30x20x50x12,60x40x40x10x20
50 cartons, 42.38 ft³, 600 kg gross.
How the CBM maths works
50 cartons of 40 × 30 × 20 cm at 12 kg each.
- One carton
0.40 × 0.30 × 0.20 m = 0.024 m³ - 50 cartons
50 × 0.024 = 1.2 m³ - Cubic feet
1.2 × 35.315 = 42.38 ft³ - Air chargeable, 1:6000
1.2 × 166.67 = 200 kg; actual 600 kg, so 600 kg - Sea LCL, W/M
max(1.2 m³, 0.6 t) = 1.2 revenue tons - Share of a 20GP
1.2 ÷ 33.2 = 3.6 %
CBM is only volume
Cubic metres tell you how much room the cargo takes, not how it will stack. Odd sizes, fragile cartons that cannot carry weight, and pallets all waste space. For a real load plan use the container loading calculator.
Air and LCL charge for whichever is bigger
Airlines compare actual weight with volume at a ratio, commonly 1:6000 (166.67 kg per m³). LCL sea freight compares cubic metres with metric tons, one to one. Both bill the larger number.
Container capacity in CBM
Typical internal volume and the 80–90 % that mixed cartons usually achieve.
Next steps
Common questions
How do I calculate CBM?
Multiply length × width × height in metres, then by the number of cartons. A 40 × 30 × 20 cm carton is 0.4 × 0.3 × 0.2 = 0.024 m³, so 50 of them are 1.2 CBM. From centimetres you can also divide L × W × H by 1,000,000.
How many CBM fit in a 20ft container?
A typical 20GP has about 33.2 m³ inside, but mixed cartons usually load to 80–90 % of that, roughly 27 to 30 m³. A 40GP holds about 67.7 m³ and a 40HQ about 76.4 m³.
What is W/M in LCL shipping?
Weight or measure: the LCL rate is charged per revenue ton, which is the greater of the volume in cubic metres and the weight in metric tons. 1.2 m³ weighing 600 kg pays for 1.2 revenue tons; 1.2 m³ weighing 2,000 kg pays for 2.
How is air freight chargeable weight worked out from CBM?
At the common 1:6000 ratio, one cubic metre counts as 166.67 kg. Multiply the CBM by 166.67 and compare it with the actual gross weight; the airline charges the higher figure. Check your forwarder's ratio.
How many cubic feet is one CBM?
One cubic metre is 35.315 cubic feet. One cubic foot is 0.0283 m³.