Free CBM Calculator

Enter package dimensions and quantity — see total cubic metres, container fit, and volumetric weight instantly

Quick presets:

Package Dimensions

Shipping Method

0.000 CBM

Total Volume

CBM Per Package
0.000
Total Actual Weight
0 kg
Volumetric Weight
0 kg
Chargeable Weight
0 kg

What Is a CBM Calculator?

A CBM calculator converts package dimensions into cubic metres — the standard unit for pricing sea freight, air cargo, and warehouse storage. Enter the length, width, and height of a package, multiply by the number of packages, and the tool returns the total volume in CBM. For ecommerce sellers importing stock from suppliers on Alibaba, shipping inventory to Amazon FBA warehouses, or sending bulk orders across Southeast Asia, knowing your exact CBM is the first step to getting accurate freight quotes.

How to Calculate CBM

The formula is straightforward. Measure each package in centimetres, then:

CBM = (Length × Width × Height) ÷ 1,000,000

For example, a box measuring 60 × 40 × 30 cm has a volume of 72,000 cm³, which equals 0.072 CBM. If you are shipping 50 of these boxes, the total shipment volume is 3.6 CBM.

If you measure in inches, convert first: 1 inch = 2.54 cm. Or use the unit toggle above and the calculator handles the conversion automatically.

CBM vs Volumetric Weight

Sea freight is priced by CBM (volume). Air freight and couriers use volumetric weight (also called dimensional weight) — whichever is greater between actual weight and volumetric weight determines the chargeable weight. The divisor varies by shipping method:

MethodDivisorFormula
Air Freight6,000(L × W × H in cm) ÷ 6,000
Courier (DHL, FedEx, UPS)5,000(L × W × H in cm) ÷ 5,000
Sea Freight1,000,000(L × W × H in cm) ÷ 1,000,000 = CBM

Light, bulky products (like pillows or lampshades) often have a volumetric weight far higher than their actual weight — meaning you pay based on volume, not mass. Heavy, compact goods (like machinery or canned food) are charged by actual weight. This calculator shows both so you can see which one your shipment will be billed on.

Shipping Container Capacities

If you are booking a full container load (FCL), you need to know how much volume fits inside. Here are the standard container capacities:

ContainerInternal Dimensions (L × W × H)Max Volume (CBM)Max Payload
20 ft5.9 × 2.35 × 2.39 m33.2 CBM28,200 kg
40 ft12.03 × 2.35 × 2.39 m67.7 CBM26,700 kg
40 ft HC12.03 × 2.35 × 2.69 m76.3 CBM26,460 kg

For cross-border ecommerce sellers importing from China, a 20 ft container is the most common for small to mid-volume shipments. Pair this with our landed cost calculator to work out the per-unit import cost including freight, duties, and taxes. Use our pallet calculator to plan how boxes stack on pallets inside the container.

Why CBM Matters for Ecommerce Sellers

Freight forwarders quote sea freight prices per CBM — typically $30–$80 per CBM for routes from China to Southeast Asia, and $50–$150 per CBM for routes to the US or Europe. Knowing your exact CBM helps you:

  • Get accurate quotes. Forwarders need CBM to give you a price. Having the number ready speeds up the quoting process.
  • Compare shipping methods. Below 15 CBM, LCL sea freight is usually cheaper than booking a full container. Above that, an FCL 20 ft container often makes more sense.
  • Budget freight costs. Multiply CBM by the per-CBM rate to estimate your shipping cost before placing a purchase order.
  • Optimise packaging. Reducing each box by even 5 cm in one dimension across hundreds of units can save a full CBM — and hundreds of dollars in freight.

If you sell on Shopee, Lazada, or TikTok Shop and regularly import inventory, calculating CBM accurately before each purchase order prevents surprises when the freight invoice arrives.

Tips for Reducing Shipping Costs

  • Right-size your boxes. Oversized packaging inflates CBM. Work with your supplier to use the smallest box that safely protects the product.
  • Consolidate shipments. Combine orders from multiple suppliers into one LCL shipment to share container space and reduce per-CBM costs.
  • Negotiate per-CBM rates. Once you ship regularly, forwarders offer volume discounts. Track your monthly CBM to negotiate better rates.
  • Consider air vs sea break-even. For small volumes under 0.5 CBM, air freight or courier may cost the same as sea freight but arrive in 5–7 days instead of 25–35. Use the break-even calculator to compare total landed costs.
  • Track inventory levels. Avoid emergency air shipments by keeping safety stock and reordering before stock runs out.

Frequently Asked Questions

How many CBM fit in a 20 ft container?

A standard 20 ft shipping container has a maximum capacity of approximately 33.2 CBM. In practice, you can typically load 25–28 CBM once you account for pallet space, stacking gaps, and loading clearance.

What is the difference between CBM and volumetric weight?

CBM (cubic metres) is a pure volume measurement used for sea freight pricing. Volumetric weight converts volume into a weight equivalent using a divisor (6,000 for air freight, 5,000 for couriers). Carriers charge whichever is greater — actual weight or volumetric weight — so both matter for cost calculations.

How do I calculate CBM from inches?

Convert inches to centimetres first by multiplying each dimension by 2.54, then use the standard formula: (L cm × W cm × H cm) ÷ 1,000,000 = CBM. Or simply switch to inches mode in the calculator above — the conversion is automatic.

Is CBM the same as cubic metres?

Yes. CBM stands for Cubic Metre (or Cubic Meter). It is the international standard unit for measuring cargo volume in shipping and logistics. One CBM equals the volume of a cube measuring 1 metre on each side, or 1,000,000 cubic centimetres.

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