How do you calculate CBM?

Length times width times height, all in metres. A 120 × 100 × 120 cm carton is 1.2 × 1.0 × 1.2 = 1.44 CBM. Working in centimetres and dividing at the end works too — by 1,000,000, not 100.

What is chargeable weight?

The larger of the actual weight and the volumetric weight. Carriers sell both space and payload and will not let you have the cheaper of the two: a pallet of pillows is charged on its volume, a pallet of tiles on its weight. Which one binds is the single thing worth knowing before quoting.

Why is the air factor 167 and the sea factor 1,000?

Because an aircraft runs out of volume long before payload and a ship does the opposite. IATA’s 1:6 divisor works out to 167 kg per cubic metre; sea LCL treats one cubic metre as one metric ton. The same pallet can therefore be a volume shipment by air and a weight shipment by sea.

How many CBM fit in a container?

About 33 in a 20 ft and 67 in a 40 ft, as loadable volume rather than internal volume — the difference is the stacking and the space you cannot use. A shipment over roughly 15 CBM is usually cheaper as a full container than as LCL groupage, which is the point at which the quote changes shape.

CBM Calculator

With length 120 cm, width 100 cm, height 120 cm, weight of one carton 250 kg and 1 more field, cbm comes to 1.440 m³ — volume. It is reached in 7 steps, the last of which is 1.44 * 1, and each one is printed on the page with its numbers filled in. The formula is the one published by IATA, not an approximation fitted to it.

Cubic meters of a shipment, and the chargeable weight that follows from it — the larger of actual and volumetric, which is what you pay on.

Formula and sources checked 16 August 2026 · How we check

Length 120 cm, Width 100 cm, Height 120 cm, Weight of one carton 250 kg

1.440 m³

Volume for the example below. Editing a field recomputes the calculator below; this figure holds the answer the page was loaded with.

It is written into the HTML rather than drawn by a script, so a search engine reading this page without running JavaScript still finds an answer.

LengthWidthHeightWeight of one cartonCartonsMode

Volume

1.440 m³

CBM of one carton: (120 / 100) * (100 / 100) * (120 / 100)1.44 m³
Total volume: 1.44 * 11.44 m³
Gross weight: 250 * 1250 kg
Volumetric weight: 1.44 * 10001,440 kg
Chargeable weight: max(250, 1440)1,440 kg
Share of a 20 ft container (33 CBM): 1.44 / 330.044 containers
Share of a 40 ft container (67 CBM): 1.44 / 670.021 containers

Several at once

A job is rarely one of anything. Work out the first, add it, change the figures and add the next — the list keeps what each line was, and totals them.

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Worked example

A 120 × 100 × 120 cm pallet is 1.44 CBM. At 250 kg its gross weight is well under the 1,440 kg the volume implies by sea, so the shipment is charged on volume — 1.44 revenue tons. Sent by air the same pallet is charged at 240 kg volumetric against 250 kg actual, and the actual weight wins.

How to work it out yourself

1.Multiply the three dimensions in metres. Centimetres divided by 100 first — a 120 cm side is 1.2 m, and forgetting that is a factor of a million.
2.Multiply by the number of identical cartons for total CBM.
3.Multiply the CBM by the mode’s volumetric factor to get the weight the carrier will treat the volume as.
4.You pay on whichever is larger, the actual weight or the volumetric one. That figure is the chargeable weight.

The formula

CBM of one carton(120 / 100) * (100 / 100) * (120 / 100)
Total volume1.44 * 1
Gross weight250 * 1
Volumetric weight1.44 * 1000
Chargeable weightmax(250, 1440)
Share of a 20 ft container (33 CBM)1.44 / 33
Share of a 40 ft container (67 CBM)1.44 / 67

Source: IATA — chargeable weight and the volumetric divisor, US Customs and Border Protection — importing basics

Questions people actually ask

How do you calculate CBM?: Length times width times height, all in metres. A 120 × 100 × 120 cm carton is 1.2 × 1.0 × 1.2 = 1.44 CBM. Working in centimetres and dividing at the end works too — by 1,000,000, not 100.
What is chargeable weight?: The larger of the actual weight and the volumetric weight. Carriers sell both space and payload and will not let you have the cheaper of the two: a pallet of pillows is charged on its volume, a pallet of tiles on its weight. Which one binds is the single thing worth knowing before quoting.
Why is the air factor 167 and the sea factor 1,000?: Because an aircraft runs out of volume long before payload and a ship does the opposite. IATA’s 1:6 divisor works out to 167 kg per cubic metre; sea LCL treats one cubic metre as one metric ton. The same pallet can therefore be a volume shipment by air and a weight shipment by sea.
How many CBM fit in a container?: About 33 in a 20 ft and 67 in a 40 ft, as loadable volume rather than internal volume — the difference is the stacking and the space you cannot use. A shipment over roughly 15 CBM is usually cheaper as a full container than as LCL groupage, which is the point at which the quote changes shape.

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