Calculate cubic metres (CBM) for sea and air freight shipments from carton dimensions and quantity. Also computes volumetric weight so you can compare against actual weight and determine the chargeable weight for your shipment.
CBM = Length × Width × Height (in cm) ÷ 1,000,000 × Quantity
Volumetric Weight = CBM × 167 kg/m³
Chargeable Weight = max(Actual Weight, Volumetric Weight)
3 cartons, each 100cm × 60cm × 50cm, total shipment weight 60kg → CBM = 0.9 m³ → Volumetric = 150.3 kg → Chargeable = 150.3 kg
CBM (Cubic Meter) is the standard volumetric unit for measuring cargo size in freight. Carriers bill the higher of actual weight vs. volumetric weight, so calculating CBM in advance lets you forecast shipping costs accurately before booking.
167 kg per cubic metre — the air-freight convention of 1 kg per 6,000 cm³. Sea freight (LCL) is usually charged per cubic metre or per tonne, whichever is greater, which works out at 1 CBM = 1,000 kg. Factors differ by carrier and route, so confirm yours with your freight forwarder before you book.
CBM measures volume. Chargeable weight is the billable weight used to calculate your freight rate — it is the higher of actual weight and volumetric weight. A bulky but light shipment (e.g. foam packaging) will be charged on its volumetric weight, not its actual weight.
Measure the maximum length, width, and height of the bounding box that contains the item. Most carriers bill on the smallest rectangular box that fully contains the shipment. Efficient, tight packing minimizes wasted cubic space and reduces freight costs.
Sea freight (FCL or LCL) usually costs far less per cubic metre than air, but takes weeks rather than days, so it suits heavy or bulky goods that are not urgent. Air earns its price on urgent, high-value or light goods. Where one becomes cheaper than the other depends on the route, the season and the cargo, so ask your forwarder to quote both for the same shipment.
Open the free Shipping CBM Calculator now, or browse the full business calculator suite.
