CBM calculator and volumetric weight calculator

1What CBM is

CBM is a cubic metre. For one carton it is length × width × height, each in metres; for a shipment it is that figure summed over every carton. Sea LCL is priced on CBM because your cartons share a container with other importers' cargo and, for most goods, the space they take is what costs money. Heavy cargo is the exception: LCL is charged on the greater of the volume and the weight at 500 kg per CBM, so 1,000 kg counts as 2 CBM. Our sea LCL rate is S$82 per CBM, hub to door, and the minimum billed is 1 CBM, so a shipment smaller than that is charged as 1 CBM. The sea freight guide covers what the rate includes.

2CBM calculation formula: cm to CBM

Carton sizes on a packing list are usually in centimetres. To convert cm to CBM, multiply length × width × height in centimetres and divide by 1,000,000, because a cubic metre is 100 × 100 × 100 cm. A 40 × 30 × 25 cm carton is 30,000 cm³, or 0.03 CBM. For many cartons of one size, multiply by the count: 335 cartons are 0.03 × 335 = 10.05 CBM. Work out each carton size separately, then add the totals.

For sea, check the weight as well. If each of those 335 cartons weighs 12 kg, they come to 4,020 kg, which counts as 8.04 CBM at 500 kg per CBM. That is less than 10.05, so the volume decides.

3Volumetric weight

Air freight has two weights. The actual weight is what the scale says. The volumetric weight is what the space a carton occupies would weigh if it were filled with something of average density, and it is worked out as length × width × height in centimetres ÷ 6000, per carton, then summed. A carton of 60 × 40 × 50 cm has a volumetric weight of 20 kg whatever is inside it.

4Chargeable weight

Air is charged on the chargeable weight: the greater of the actual weight and the volumetric weight. Light, bulky cargo such as cushion covers or foam is charged on volume; dense cargo such as tiles or metal parts is charged on the scale. Our air rate is from S$6.50 per kg of chargeable weight, general cargo, with a minimum of 10 kg. The air freight guide explains when air is worth it and when sea is the better trade. For air on its own, the chargeable weight calculator puts the three weights side by side.

5A worked example

Two carton types, measured in centimetres. CBM is the product of the three sides in metres; volumetric weight is the product in centimetres divided by 6000. Both are per carton and then multiplied by the quantity.

By sea this shipment is 1.38 CBM, above the 1 CBM minimum. Its 100 kg would count as only 0.2 CBM at 500 kg per CBM, so the volume decides and it is billed on 1.38 CBM at S$82 per CBM. By air the volumetric weight is 230 kg against an actual weight of 100 kg, so the chargeable weight is 230 kg, well above the 10 kg minimum. The guide to shipping from China to Singapore goes through when each mode makes sense.

6How many kg is 1 CBM?

It depends on the mode. A cubic metre measures space and a kilogram measures weight, and sea and air each have their own rule for turning one into the other when a shipment is priced.

Take 2.8 CBM. By sea there is no volumetric weight; the weight is turned into CBM instead. The shipment is billed as 2.8 CBM unless it weighs more than 2.8 × 500 = 1,400 kg, and the same cartons at 1,750 kg would count as 3.5 CBM. By air, 2.8 CBM is 2,800,000 cm³, which ÷ 6000 is about 466.7 kg of volumetric weight, charged unless the scale reads more. Some express couriers divide by 5000 instead, which makes the same 2.8 CBM 560 kg; our air freight uses 6000.

7Already know your CBM? The sea and air price from the volume

Most suppliers put the total volume on the packing list or quote it when the order is ready, so you may not need to measure anything. Choose I know my CBM at the top of the calculator, type the volume, and the sea LCL and air freight figures appear side by side. By sea, the price is the CBM × S$82, hub to door, with the 1 CBM minimum: 2.5 CBM is 2.5 × S$82. By air, the same 2.5 CBM is about 416.7 kg of volumetric weight (CBM × 1,000,000 ÷ 6000), charged at S$6.50 per kg unless the scale reads more.

Add the total weight if you have it. By sea it only matters for dense cargo: the shipment is charged on the weight once it passes 500 kg per CBM. By air the weight is checked against the volumetric figure and the greater one is charged, so a heavy 1 CBM pallet at 300 kg is priced on 300 kg, not 166.7. The carton count is optional and is carried into the quote request with the other figures.

8Indicative, not confirmed

The figures the calculator shows are indicative, from our published rates. Your confirmed quote is the final figure. The quote also carries what the calculator cannot know: GST at 9% on the import value (the import GST calculator works that out), any special handling, and whether anything on the restricted goods list needs paperwork. Use the figures in a quote request: the instant quote appears as you type, and the confirmed quote follows in writing within a few hours.