What is W/M (weight or measure) in shipping?
In LCL, one cubic meter is treated as equal to 1,000 kg. The shipment's weight in metric tons and its volume in cubic meters are compared, and the larger number becomes the revenue ton, also called the freight ton, that the rate is multiplied by. Rates are quoted per W/M, and consolidators usually apply a minimum of one revenue ton per shipment.
W/M is the ocean version of chargeable weight, but it is far more generous to light cargo than air freight is: 1,000 kg per cubic meter at sea against about 167 kg by air. Besides the ocean rate, many LCL origin and destination charges, such as container freight station handling, are also billed per W/M, and each line can carry its own minimum.
Example: 3.2 m³ of furniture weighing 1,800 kg is billed on 3.2 revenue tons, because its volume is larger than its 1.8 metric tons. Machine parts of 2 m³ weighing 4,500 kg are billed on 4.5 revenue tons, by weight. At an example rate of USD 40 per W/M, the furniture costs USD 128 in ocean freight before local charges are added.