Air freight is faster and usually far more expensive per kilogram; ocean freight is cheaper but slower. The right choice depends on more than the freight quote. This guide shows how to compare the two on total cost, including chargeable weight and the cost of goods sitting in transit. Freight rates change often, so use current quotes from your forwarder rather than published averages.
Step 1: calculate chargeable weight
Carriers charge on whichever is greater: the actual weight or the volumetric (dimensional) weight. For air cargo, volumetric weight is commonly calculated as length × width × height in centimetres divided by 6,000, giving kilograms. Light, bulky goods can therefore cost much more to fly than their actual weight suggests.
Ocean freight is priced per container (FCL) or per cubic metre or tonne for less-than-container loads (LCL). Ask your forwarder which basis applies, because conversion factors vary by carrier and service.
Step 2: compare door-to-door cost, not port-to-port
Add origin charges, export clearance, main freight, destination charges, import clearance and final delivery. LCL shipments often carry consolidation and handling fees that make small ocean shipments less cheap than they look. Make sure both quotes use the same Incoterms® rule so you are comparing the same scope.
Step 3: price the time
Goods in transit are capital you cannot use. A simple estimate of holding cost is: goods value × annual cost of capital × (extra transit days ÷ 365). Add the cost of a stock-out, a missed launch or a production line waiting for parts. If those costs exceed the freight premium, air can be the cheaper option overall.
- High value, low volume: air is often justified.
- Low value, high volume: ocean almost always wins.
- Urgent replacement parts or samples: air, even at a premium.
- Seasonal goods: plan ocean shipments early instead of paying for air later.
Ask suppliers to quote both
When you send an RFQ, ask for the packed dimensions and weights per carton and per shipment. With that, your forwarder can price both modes. On Quotendra, add packing details and the delivery basis to the request so suppliers' quotes can be compared on the same terms.