The Logic of Air Freight Rates: Understanding Weight Breaks
Air freight pricing is not based on a single, flat rate. Instead, it operates on a tiered system known as "weight breaks." This system is designed to incentivize shippers to send larger volumes by offering a lower price per kilogram as the total chargeable weight of the shipment increases. Understanding how to leverage these breaks is fundamental to optimizing your logistics spend.
Airlines and freight forwarders establish a rate structure with several tiers. For example, the rate for a shipment over 100 kg will be lower than the rate for a shipment under 45 kg. This calculator helps you input a standard rate card and your shipment's weight to see which tier you fall into and what your base freight cost will be.
Key Concepts in Rate Calculation
- Minimum Charge (MIN): This is the absolute lowest amount an airline will charge to move a shipment, regardless of its size or weight. If the calculated freight charge is lower than the MIN, you will be billed the MIN charge. This covers the basic administrative and handling costs for even the smallest shipment.
- Normal Rate (N): This is the rate for shipments that are too small to qualify for the first weight break, typically those under 45 kg.
- Quantity Rates (Q): These are the tiered rates offered at specific weight breaks. Common breaks are +45 kg, +100 kg, +300 kg, and +500 kg. The "Q45" rate is the per-kilogram price for shipments weighing 45 kg or more.
- Breakpoint Calculation: A crucial concept is the "breakpoint." Sometimes, it is cheaper to pay for a higher weight to access a lower rate. For example, if you have a 40 kg shipment, it might be cheaper to declare it as 45 kg to get the lower "+45 kg" rate, rather than paying the higher "Normal" rate for 40 kg. Freight forwarders automatically perform this calculation to give you the lowest possible price.
Example of a Breakpoint
Let's say you have a shipment of 42 kg and the rates are:
Normal Rate (<45 kg): $5.00/kg
+45 kg Rate: $4.00/kg
Option 1 (Actual Weight): 42 kg × $5.00/kg = $210.00
Option 2 (Breakpoint): 45 kg × $4.00/kg = $180.00
In this case, it is significantly cheaper to bill the shipment "as 45 kg". The Chargeable Weight becomes 45 kg, and the total cost is $180.00. This calculator will automatically apply the most favorable calculation.
How to Use the Calculator
- From your freight forwarder's quote or rate sheet, enter the rate for each weight break. If a certain break is not offered, you can leave it as 0.
- Enter the Minimum (MIN) charge for a shipment.
- Enter the specific Chargeable Weight of your shipment in kilograms.
- Click "Calculate Rate & Total". The calculator will determine which rate is most economical (applying the breakpoint logic) and show both the applicable rate and the final base freight charge.