How to use
- Pick the unit you measured in: cm, mm, m or inches.
- Enter length, width, height and quantity for each carton size. Use Add box for every additional size.
- Optionally enter the total gross weight to get the LCL revenue ton (R/T).
- Read the total CBM, cubic feet and container fill, and use Copy to grab the total.
Formulas
CBM (cubic meters, m³) is the standard volume measure for ocean freight quotes and container planning.
| Item | Formula |
|---|---|
| One carton | length (m) × width (m) × height (m) |
| Measured in cm | L × W × H (cm) ÷ 1,000,000 |
| Measured in inches | L × W × H (in) × 0.0254³ — or ÷ 1,728 for cubic feet |
| Total CBM | Sum of (carton CBM × quantity) |
| Cubic feet | CBM × 35.3147 (1 ft = 0.3048 m) |
| Revenue ton (R/T) | The larger of CBM and gross weight in metric tons |
Example
| Cartons | Calculation | CBM |
|---|---|---|
| 50 × 40 × 30 cm, 20 cartons | 0.5 × 0.4 × 0.3 × 20 | 1.2 |
| 60 × 40 × 40 cm, 10 cartons | 0.6 × 0.4 × 0.4 × 10 | 0.96 |
| Total | 2.16 CBM (about 76.28 ft³) |
With a gross weight of 350 kg (0.35 t), volume is larger, so the shipment rates at 2.16 R/T. It would take up about 6.5% of a 20GP container’s internal volume.
Revenue tons and container capacity
LCL (less-than-container-load) freight is usually charged per revenue ton, also written W/M: 1 CBM or 1,000 kg, whichever is greater. Light, bulky cargo is charged by volume; dense cargo by weight. Many forwarders also apply a minimum, such as 1 R/T.
| Container | Typical internal dimensions (m) | Internal volume |
|---|---|---|
| 20GP | 5.898 × 2.352 × 2.393 | ≈ 33.20 m³ |
| 40GP | 12.032 × 2.352 × 2.393 | ≈ 67.72 m³ |
| 40HQ | 12.032 × 2.352 × 2.698 | ≈ 76.35 m³ |
Fill percentages are measured against these internal volumes. Gaps between cartons, stacking limits and pallets mean the practical loadable volume is usually around 80–90%, so a fill above 80% may not fit in one container.
Things to keep in mind
- Measure the outer dimensions of each packed carton. If cargo ships on pallets, measure the whole loaded pallet.
- Internal dimensions vary slightly between containers, and the door opening is smaller than the interior. For heavy cargo, the maximum payload often runs out before the space does.
- Air freight and express couriers charge by volumetric weight rather than CBM — see the volumetric weight calculator.
FAQ
How many cartons fit in 1 CBM?
Roughly 1 ÷ the CBM of one carton. A 50 × 40 × 30 cm carton (0.06 CBM) gives about 16.7, though real-world stacking fits fewer.
How many kilograms is 1 CBM?
CBM measures volume, so there’s no fixed conversion. Ocean LCL treats 1 CBM and 1,000 kg as the same 1 R/T, while air freight with a 6,000 divisor treats 1 CBM as about 166.67 kg of volumetric weight.
Can I measure in inches?
Yes. Choose inch and the tool converts using the exact definition 1 in = 2.54 cm.