One CBM (cubic meter) is a volume one meter long, one meter wide and one meter high. It equals about 35.3 cubic feet or 1,000 liters. Ocean and air freight are quoted in CBM because volume, not weight, usually drives the cost of light freight.

How do I convert CBM to kg?

It depends on the mode. For air freight, multiply CBM by 167 to get the volumetric (chargeable) weight in kg under the IATA 1:6000 rule. For ocean LCL, one revenue ton is the greater of 1 CBM or 1,000 kg. The actual weight of the goods is separate; carriers bill the greater of volume and weight.

How many CBM fit in a container?

A 20-foot container holds about 33 CBM and a 40-foot about 67 CBM when empty. Because cartons don't stack perfectly, a realistic load is roughly 80-90% of that: about 25-28 CBM in a 20-foot and 55-58 CBM in a 40-foot.

How to Calculate CBM (Cubic Meters)

Q: How do I calculate CBM?

Multiply the carton's length, width and height in meters, then multiply by the quantity. If you measured in centimeters, multiply the three sides and divide by 1,000,000. A 120x100x150 cm carton is 1.8 CBM. For a mixed load, calculate each carton size separately and add the results.

CBM — cubic meters — is the volume of your freight, and it’s the number every ocean and air quote is built on. Multiply a carton’s length × width × height in meters, then multiply by the quantity. Measuring in centimeters? Multiply the three sides and divide by 1,000,000. A 120×100×150 cm carton is 1.8 CBM. Here’s the full formula in every unit, how CBM becomes a billing weight, and how much fits in a container — with the free calculator one click away.

What CBM is

CBM stands for cubic meter — one meter long, one meter wide, one meter high. It’s simply the amount of space your freight occupies, expressed in metric volume. Ocean LCL and international air freight are quoted and planned in CBM, because for most freight the space it takes up matters more than what it weighs.

One CBM equals about 35.3 cubic feet, or 1,000 liters. Get the CBM right and everything downstream — the quote, the container plan, the chargeable-weight check — lines up.

The CBM formula

Multiply the three sides of a carton and put them in meters. In centimeters: (L × W × H) ÷ 1,000,000. In millimeters: ÷ 1,000,000,000. In inches: ÷ 61,024 (there are 61,024 cubic inches in a cubic meter). Then multiply by how many identical cartons you’re shipping.

A carton measuring 120×100×150 cm works out to 1,800,000 cm³ ÷ 1,000,000 = 1.8 CBM; ship two and it’s 3.6 CBM. For a mixed load, calculate a line per carton size and add them up. The exact per-unit breakdown lives in the CBM formula for cm, inches and mm.

CBM is the currency of ocean and air freight. If you know the cube, you can read any quote.

CBM to chargeable weight

Carriers won’t haul light, bulky freight cheaply just because the scale is kind. Both air and ocean convert your cube into a billing weight and charge the greater of that or the actual weight. Air uses volumetric weight: CBM × 167 kg/m³ (the IATA 1:6000 rule). Ocean LCL bills a revenue ton — the greater of 1 CBM or 1,000 kg.

So a 3 CBM / 300 kg shipment bills as 3 revenue tons by sea (volume wins) and about 500 kg by air. Full worked examples are in converting CBM to kg.

How much CBM fits in a container

A 20′ container holds roughly 33 CBM empty, a 40′ about 67 CBM, and a 40′ high-cube about 76 CBM. Cartons never tile perfectly, so a realistic plan fills to 80–90 % — call it ~25–28 CBM in a 20′ and ~55–58 CBM in a 40′. Use those practical figures to sanity-check whether your load actually fits before you book.