Calculate the cubic meter (CBM) volume of your cargo and find out exactly how many units fit in a 20ft, 40ft, or 40ft High Cube shipping container — instantly and free.
Understanding standard container dimensions helps you plan your shipment before calculating. Here are the internal dimensions and usable capacities for the three most common container types.
| Container | Internal Length | Internal Width | Internal Height | Volume (CBM) | Max Gross Weight |
|---|---|---|---|---|---|
| 20ft Standard | 5.89 m | 2.35 m | 2.39 m | ~33 CBM | ~28,000 kg |
| 40ft Standard | 12.03 m | 2.35 m | 2.39 m | ~67 CBM | ~30,400 kg |
| 40ft High Cube | 12.03 m | 2.35 m | 2.69 m | ~76 CBM | ~30,400 kg |
💡 Practical Tip: Always aim for 85-90% container utilization in your calculations, not 100% — you need working room for stacking, securing cargo, and ensuring weight is distributed safely.
CBM — short for Cubic Meter — is the international standard unit for measuring the volume of cargo. It's the single most important number in sea freight pricing, because ocean carriers charge based on either the actual weight (in metric tonnes) or the volume (in CBM), whichever produces the higher freight charge.
This pricing method is called "weight or measure" (W/M) in the freight industry. For most manufactured goods, consumer products, and e-commerce inventory, volume is the determining factor, not weight — meaning a large, lightweight shipment costs more per kilogram than a heavy, compact one.
The formula is straightforward:
For multiple units of the same box: multiply the single-unit CBM by the quantity to get total shipment volume.
Suppose you're shipping 200 boxes of phone cases, each measuring 50cm × 40cm × 30cm. Single box CBM = (50 × 40 × 30) ÷ 1,000,000 = 0.06 CBM. Total for 200 boxes = 0.06 × 200 = 12 CBM. At a typical LCL rate of $30-50 per CBM, your sea freight cost estimate is $360-$600 — before any additional charges.
| Freight Type | CBM Equivalent to 1 Tonne | When Volume Wins |
|---|---|---|
| Sea Freight (LCL) | 1 CBM = 1 metric tonne | Cargo density under 1,000 kg/CBM |
| Air Freight | 1 CBM = 167 kg (DIM factor 6000) | Cargo density under 167 kg/CBM |
| Express Couriers | Varies (5000-6000 DIM factor) | Most packaged consumer goods |
One of the most important decisions in sea freight is whether to ship LCL (Less than Container Load) or book a full container (FCL). CBM is the key input for this decision.
💡 Rule of Thumb: If your total shipment exceeds 15 CBM, get FCL quotes alongside your LCL rate — FCL often becomes cheaper per CBM at this volume, and the faster transit time and reduced handling adds extra value.
If you have multiple product types with different dimensions, calculate each line separately and add the totals together to get your full shipment CBM.
CBM stands for Cubic Meter, the standard unit of volume in international freight. It's calculated by multiplying a package's length × width × height in meters. Carriers charge based on CBM or actual weight, whichever is higher.
Multiply length × width × height in centimeters, then divide by 1,000,000. Example: a 100 × 80 × 60 cm box = 480,000 ÷ 1,000,000 = 0.48 CBM.
A standard 20ft container has approximately 33 CBM of internal volume. Practical usable capacity is typically 25-28 CBM when accounting for wall thickness and loading constraints.
The 40ft HC (High Cube) is 30cm taller than a standard 40ft, giving approximately 76 CBM vs 67 CBM. HC containers are ideal for lightweight, bulky cargo where height matters.
LCL is generally better for shipments under 12-15 CBM. FCL becomes cost-effective above this threshold and offers faster transit and less cargo handling.
Most LCL carriers charge a minimum of 1 CBM, even for smaller shipments. Billing increments are typically 0.1 CBM.
Sea freight (LCL) is priced per CBM. Carriers charge the higher of actual weight (tonnes) or volume (CBM), so reducing CBM through better packaging directly reduces freight cost.
Approximately 20-21 Euro pallets (120 × 80cm) or 23-24 standard US pallets (120 × 100cm) in a single layer. Double-stacking depends on cargo weight and stackability.
Yes — mixing sizes is encouraged because smaller boxes can fill gaps between larger ones, improving utilization and reducing per-unit shipping cost.
Yes, completely free with no registration required. Calculate CBM and container load for any shipment instantly.
Use these free tools alongside the CBM calculator to fully plan and cost your international shipment.