One of the most common questions in international shipping is deceptively simple: “Why does this shipment cost more than another one with the same weight?”
For many importers, especially those new to international trade, shipping costs can feel inconsistent or even arbitrary. In reality, shipping pricing follows very specific rules that depend on much more than weight alone.
To understand shipping costs properly, three elements must always be considered together: weight, volume (CBM), and product type. Ignoring any one of these leads to incorrect expectations and frequent misunderstandings.
Weight: Gross Weight vs Chargeable Weight
Weight is often the first metric people focus on, but it is rarely the deciding factor on its own. In shipping, what matters is not just how heavy a shipment is, but how that weight relates to the space it occupies.
There are two types of weight used in logistics. Gross weight refers to the total weight of the goods including packaging. Chargeable weight, however, is what carriers actually use to calculate costs. Depending on the shipping method, chargeable weight may be based on actual weight or on volume.
For air freight, volumetric weight is often more important than physical weight. Light but bulky products can cost more to ship than heavy compact goods. This is because aircraft space is limited, and airlines charge based on how much space cargo occupies rather than how heavy it is.
For sea freight, weight becomes less significant once certain thresholds are reached, and volume often plays a larger role—especially for LCL (Less than Container Load) shipments.
CBM (Cubic Meter): The Space Your Cargo Occupies
CBM, or cubic meter, measures the physical volume of your shipment. It is calculated using the length, width, and height of the packed goods. In sea freight, CBM is one of the most critical pricing factors.
For LCL shipments, freight rates are usually quoted per CBM, not per kilogram. This means that a shipment with low weight but high volume can cost more than a smaller, heavier shipment. Two shipments weighing the same may have very different CBMs depending on packaging efficiency and product shape.
Even small differences in packaging can significantly impact CBM. Poor palletization, oversized cartons, or excessive protective materials can increase volume and, as a result, increase shipping costs. This is why professional packing and accurate measurements are essential before requesting a quotation.
For FCL (Full Container Load), CBM determines whether your goods fit efficiently into a 20-foot or 40-foot container. Shipping air inside a container is essentially wasted money.
Product Type: The Hidden Cost Driver
Product type is one of the most misunderstood elements in shipping cost calculations. Many importers assume that if two products have the same weight and CBM, they should cost the same to ship. This is rarely true.
Certain products are classified as sensitive, regulated, fragile, high-value, or hazardous, which affects how they must be handled, stored, and transported. For example, certain electronics products may require special handling, careful stacking, moisture protection, or additional documentation. Batteries, liquids, chemicals, or branded goods often involve extra compliance steps and higher risk for carriers.
Some products are subject to additional inspections, certificates, or customs scrutiny, which increases handling time and cost. Others may require reinforced packaging, insurance adjustments, or specific loading methods inside containers.
Even within the same product category, differences in material composition or intended use can affect shipping costs and customs treatment.
Why Two Shipments With the Same Weight Cost Differently
When all these factors are combined, it becomes clear why shipping costs vary. Two shipments may weigh exactly the same, but one may occupy more space, require special handling, or involve higher customs risk. One may be packed efficiently on pallets, while the other may be loosely boxed. One may move as general cargo, while the other requires regulatory clearance or certification.
In addition, route, seasonality, port congestion, and carrier availability also influence pricing. Shipping costs are dynamic, not fixed, and quotations are always based on a specific set of variables at a specific time.
This is why comparing shipping quotes without understanding what they include often leads to confusion. A lower quote may exclude key services, while a higher one may reflect more accurate assumptions and fewer surprises later.
Why Professional Assessment Matters
Factories typically provide shipping information based on convenience, not optimization. They focus on getting goods out the door, not on minimizing landed cost for the buyer. Inexperienced importers may rely on rough estimates or outdated assumptions, which often results in unexpected charges at the port of destination.
At Alanovas, we analyze shipping costs holistically. We assess weight, CBM, and product type together, then evaluate how these factors interact with the chosen shipping method, destination regulations, and client preferences. Our goal is not to provide the cheapest number on paper, but the most accurate and predictable cost structure.
By identifying these factors early, we help clients avoid surprises, choose the right shipping strategy, and understand exactly what they are paying for before committing to production or transport
