Difference between Dimensional Weight and Actual Weight

Have you ever come across your shipping companies charging $25 to ship a  2-pound pillow?

You’re not alone.

The shipment cost is often calculated for the space it occupies and not for the weight it weighs.

This is where you should know the difference between dimensional weight and actual weight. 

In this blog we will break down the difference between dimensional weight and actual weight. 

What is Actual Weight?

Actual weight AKA physical weight is the real weight of a package measured on a scale, also known as the gross weight.

It includes the weight of the product, packaging, and any materials inside the box.

In short: It’s what your package physically weighs.

For example:

If you place a sealed box on a scale and it reads 12 kg, that’s the actual weight, regardless of how big or small the box is.

What is dimensional weight?

Dimensional weight (also called volumetric weight) is a pricing technique used by shipping carriers to calculate the cost of a package based on how much space it takes up, not just how much it weighs.

Think of a large box filled with pillows. It takes up a huge amount of space but barely weighs a few kilos. 

When freight forwarders charge only by actual weight, they lose money on bulky, lightweight shipments because these boxes consume space that could’ve been used for heavier, more profitable cargo.

In short, low-density shipments hurt freight forwarders' efficiency. They're moving air instead of weight.

How to Calculate Dimensional Weight?

Dimensional weight (DIM weight) isn’t calculated the same across all shipping methods.

Whether you're using air, ocean, ground, or express services, carriers apply different formulas and divisors based on how they manage space and cargo efficiency. 

Learn more

Here's how DIM weight works across each mode:

Air Freight: Volume Drives the Rate

In air freight, space is a premium. Carriers almost always charge based on the higher of actual weight or dimensional weight.

Formula:

Length × Width × Height (in cm) ÷ 6,000

or

Length × Width × Height (in inches) ÷ 166 (some carriers use 194)

166 = DIMS factor

Standard IATA factor: 1 CBM = 167 kg (used for chargeable weight)

Some carriers (e.g., DHL, Emirates) use different divisors depending on aircraft and routes

Applies heavily to ecommerce, fashion, electronics items that are lightweight but bulky

Ocean Freight: Based on Cubic Meters or Weight

In sea freight, volume is king, especially for LCL (Less than Container Load) shipments.

Billing Rule (LCL): 1 CBM = 1,000 kg

The higher of volume (CBM) or actual weight (in metric tons) is used

Note - If your cargo measures 3 CBM and weighs 1,200 kg, you’ll be charged for 3 CBM. If it measures 2 CBM but weighs 3,000 kg, you’ll be charged for 3 tons

For FCL (Full Container Load) shipments, carriers typically charge per container, not by dimensional weight but optimizing space still impacts your per-unit cost.

To know the difference between FCL and LCL read 

Ground Freight: DIM Weight with Exceptions

Many ground carriers, especially in North America, apply DIM weight similar to air freight  particularly for parcel and LTL (less-than-truckload) shipments.

Typical formula:(L × W × H in inches) ÷ 139 (FedEx/UPS standard)

139 = DIMS factor

Applied for larger, lightweight items that take up space in delivery vans

Truckload (FTL) may rely more on pallet count and weight per axle than dimensional weight

Some regional carriers may waive DIM pricing under certain conditions and always confirm with your forwarder.

Express Couriers: UPS, FedEx, DHL

Major courier companies universally apply DIM weight to parcels

Formula: L × W × H (in inches) ÷ 139 (for domestic)

139 = DIMS factor

May vary for international services or economy/priority tiers

Even a lightweight box (e.g., 3 lbs) can be charged at 10+ lbs if the box is large

DIM weight is especially relevant for ecommerce shippers using express delivery

Tip: Small packaging adjustments can significantly reduce your bill.

Why Do Freight Carriers Use Dimensional Weight Pricing?

Freight carriers use dimensional weight (also called volumetric weight) pricing to make sure they're fairly compensated for the space your cargo takes up—not just its weight.

Here’s why it matters:

• Large, lightweight items can take up a lot of space but weigh very little, so DIM weight ensures carriers get paid fairly for the space used in their trucks, planes, or containers.
• Prevents shippers from using oversized boxes filled with air or padding. It also encourages smarter, more compact packaging practices.
• Efficient space usage leads to fewer trips and optimized fuel consumption, helps logistics teams load cargo more effectively.
• Without DIM weight pricing, bulky items would underpay for shipping. It balances the cost between lightweight and dense cargo.
• As a freight forwarder, we calculate both actual and dimensional weight. We choose the most cost-effective option for you, whether it’s air, ocean, or courier.

Learn more

How Dimensional Weight Affects Your Shipping Cost

1. Revenue Optimization for Carriers
   1. Carriers operate on thin margins, especially in air and express freight.
   2. If charges were based only on actual weight, large but light shipments would reduce revenue per shipment.
   3. DIM pricing standardizes revenue per cubic foot, ensuring every unit of space earns a minimum return.

🧮 It aligns shipping rates with both weight and spatial economics maximizing profitability per load.

2. Cost of Opportunity in Cargo Space
   1. Every shipment occupies volume that could be used for denser, higher-yield cargo.
   2. When a large, low-weight package is moved, carriers miss the opportunity to transport higher-paying freight in that space.
   3. DIM pricing is a way to penalize inefficient cargo, offsetting that lost opportunity.

📦 Think of it like airplane seating—an oversized passenger taking two seats would be charged more.

3. Fuel Consumption and Load Balance
   1. Freight that’s bulky (even if light) impacts aerodynamics, center of gravity, and fuel usage.
   2. Aircraft and trucks are engineered to maintain load balance and maximize payload efficiency.
   3. High-volume freight increases drag or affects vehicle load capacity, raising operational fuel costs.

🚚 Carriers pass this hidden operational cost back to shippers via dimensional weight.

4. Handling and Warehouse Optimization
   1. Bulky shipments require more space in warehouses, more labor, and sometimes special equipment for handling.
   2. Carriers incur higher storage, staging, and movement costs for large-volume items.
   3. DIM weight allows them to recover these hidden logistics expenses.

🏗️ Volume matters as much as weight when planning warehouse and loading dock capacity.

5. Global Carrier Standardization
   1. Major global freight forwarders use DIM weight to align rate structures across markets.
   2. Helps maintain consistency across international shipping routes and multimodal transport.
   3. Without DIM, pricing would vary wildly and be difficult to manage across regions.

🌐 It supports a predictable, scalable freight ecosystem across ocean, air, and land.

6. Encourages Shippers to Optimize Packaging
   1. DIM weight is not just a cost model, it’s a behavioral incentive.
   2. Forces businesses to think about smart packaging, void fill reduction, and logistics engineering.
   3. Result? Lower environmental impact, better space utilization, and fewer shipping errors.

🌱 Incentivizing efficient packaging reduces carbon footprint and overall industry costs.

How to Reduce Dimensional Weight Charges

Reducing DIM weight is all about maximizing space efficiency. Here are proven ways to keep your chargeable weight (and costs) down:

• Choose packaging that matches the product’s dimensions closely.
• Make sure you eliminate oversized boxes that add unnecessary volume.
• Avoid excessive padding and void fill, use only what’s necessary for protection and do not overkill.
• Break down furniture, equipment, or bulky products into smaller parts and ship flat or stackable components to reduce total volume.
• Avoid awkward box shapes that take up more cubic space and use stackable, rectangular boxes for better pallet or container efficiency.
• Combine multiple small shipments into one larger, optimized load, it helps to reduce total packaging waste and maximizes cubic space usage.

Work With a Freight Forwarder Who Understands DIM Pricing

• Our team can assess your current packaging and suggest space-saving alternatives.
• We help clients rework their packaging to minimize DIM weight without compromising protection.
• We recommend the most cost-effective mode and offer freight consulting to reduce overcharges.

Learn more

Difference between actual weight and Dimensional weight 

Final Thoughts

Now that you understand the difference between dimensional and actual weight, here’s how to avoid surprise charges and keep control shipping costs:

• Measure every shipment's  length, width, and height matter just as much as weight.
• Calculate both actual and DIM weight  and know which one your carrier uses for billing.
• Use the right-sized boxes, avoid oversized packaging whenever possible.
• Consolidate small shipments, especially if you ship LCL or with couriers.
• Consult your freight forwarder, a quick review of your packaging strategy can save big.

With a few smart adjustments, you can reduce shipping costs, without compromising on delivery or quality.

1. Why does air freight cost more than ocean freight for the same cargo?

Air freight is priced based on speed and space. DIM weight pricing applies strictly, and aircraft have lower space and weight capacity than ships, which results in higher per-kg costs.

2. How does dimensional weight affect ecommerce shipping costs?

Ecommerce sellers often deal with high-volume, low-weight items like clothes, shoes, and accessories. These are subject to DIM weight pricing, making packaging design a key factor in cost control.

3. Does DIM weight affect import duties or customs clearance?

No, customs duties are calculated on actual weight and declared value, not dimensional weight. DIM weight only affects freight cost charged by the carrier.

4. Do sea freight shipments use dimensional weight?

Yes, but mostly for LCL shipments. Ocean freight forwarders bill based on the greater of actual weight or volume (1 CBM = 1 ton). For FCL, you pay per container, so DIM weight doesn’t usually apply.

5. Why is my shipping bill higher than expected even though my cargo is lightweight?

It’s likely due to dimensional weight pricing. If your package takes up more space than its weight justifies, the carrier will charge you based on volume — not the scale weight.

6. What is Billable Weight?

Billable weight is the weight that shipping carriers use to determine the price of a shipment. It is the greater value between a package's actual weight (how much it weighs on a scale) and its dimensional weight (a value based on its size).