Dimensional Weight Shipping Calculator

FedEx, UPS & USPS Dimensional Weight Calculator

Billed Weight Zone {{ n+1 }}
{{billUPS}} lbs {{ value }} *
{{billFedEx}} lbs {{ value }} *
{{billUSPS}} lbs {{ value }} *

Scroll down to read explanation

DIM Weight {{dimWeightUps}} lbs {{dimWeightFedEx}} lbs {{dimWeightUSPS}} lbs
Billed Weight {{billUPS}} lbs {{billFedEx}} lbs {{billUSPS}} lbs
Zone {{ n+1 }} {{getZoneData('ups',n-1)}} * {{getZoneData('fedex',n-1)}} * {{getZoneData('usps',n-1)}} *

* Prices shown are each carrier's base daily rates. Red Stag clients receive substantial shipping discounts off the carrier's base rates. Please Contact Us for more information.

Base Shipping Rate Calculation

UPS will bill you for your parcel at {{billUPS | decimalonly}} pounds since the DIM weight is not greater than the parcel's actual weight.

FedEx will bill you for your parcel at {{billFedEx | decimalonly}} pounds since the DIM weight is not greater than the parcel's actual weight.

USPS will bill you for your parcel at {{billUSPS}} pounds since the DIM weight is not greater than the parcel's actual weight.

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What is Dimensional Weight?

Dimensional or DIM weight pricing is a formula that carriers use to determine the cost to ship a package. Dimensional weight pricing allows carries to incorporate the size of the packages they ship into their pricing structure. After all, the number of packages that can fit on one truck or in one container depends as much on the size of the box as its weight.

Prior to 2015, the cost to ship a parcel was based on a very simple formula. Carriers used a table that would assign a base shipping rate for every combination of weight (1-150 lbs) and zones (distance to be shipped). The heavier the package and/or the further it needed to travel, the more it cost to ship. On the surface, this formula makes perfect sense, until you think about one other factor: fixed amount of space available in their trucks and aircraft. In 2015 FedEx, USPS, and UPS introduced a new pricing model called Dimensional Weight.


Why Dimensional Weight Pricing?

The purpose of dimensional weight pricing is to calculate FedEx, UPS, and USPS shipping costs factoring in on the amount of space a parcel will take up and charge accordingly. The space each package occupies is at a premium, so carriers need to factor space – dimensions – into their pricing in addition to the weight of the parcel. If your package is heavy or small, you don’t need to worry about DIM prices. You’ll pay for USPS shipping or shipping with other carriers based solely on the actual package weight. However, if you ship something relatively light in a large box, you may pay more than you expected to.

This eCommerce shipping crunch makes space in delivery trucks and vans a precious commodity. DIM weight pricing allows carriers to charge for space as well as weight.


What Is a DIM factor?

Each shipper uses a number called the DIM factor to calculate a package’s dimensional weight. The cost of shipping is whichever is greater between the DIM weight and the actual weight. A package with a dimensional weight of 8 pounds and an actual weight of 5 pounds would ship as an 8-pounds parcel. If a package with the same dimensions had an actual weight of 10 pounds, the shipping charge would be based on the actual weight of 10 pounds.

UPS, FedEx, and USPS each sets its own DIM factor. This is the number by which you multiply the package dimensions to find the DIM weight. These companies update their DIM factors every year. In 2019, the US Postal Service changed its DIM weight pricing model to apply to all packages greater than 1,728 cubic inches. DIM weight pricing doesn’t apply to USPS flat rate shipments.

DIM Weight v. Actual Weight


How to Calculate Dimensional Weight

The FedEx, UPS, and USPS dimensional weight formulas all follow the same basic guidelines: Determine the package dimensions, and divide by a DIM Factor:

(Parcel Height x Parcel Width x Parcel Length)/Dim Factor = DIM Weight*

*Rounded up to the nearest whole number

If your package is relatively heavy and small, the actual weight will probably be more than the calculated dimensional weight (think about shipping small and heavy iron dumbbells). In that case, your FedEx, UPS, or USPS shipping cost will be based on the actual weight of the package.

However, if the volumetric or dimensional weight is more than the actual weight, you’ll be charged based on the volumetric weight (imagine shipping a lightweight but large titanium bike frame). These larger parcels are more likely to be adversely affected by dimensional weight pricing.

DIM weight example

FedEx, UPS and USPS will always use the larger value between DIM Weight or Actual Weight, as the final Billed Weight.


FedEx Dimensional Weight in 2020

FedEx changed its DIM Factor from 166 to 139 beginning in 2017 and it remains the same today.

For example, in 2016, if you shipped a 10” x 10” x 10” package that weighed 5 pounds, your old DIM weight calculation would be (10 x 10 x 10)/166 = 7 pounds dimensional weight. You would be charged for shipping a 7-pound package.

FedEx DIM Weight

With the updated DIM Factor, the billable weight of that same package is now 8 pounds. (10 x 10 x 10)/139 = 8 pounds. Your FedEx shipping charges would be based on the volumetric weight of 8 pounds, since it’s greater than the actual weight.

FedEx has also changed its base billing rates. Both FedEx and UPS used to have the same base billing rates. Now, for packages of the same rate, UPS has a slight price advantage in Zones 2 through 4. FedEx tends to be slightly cheaper in Zones 5 through 8.


UPS Dimensional Weight in 2020

UPS on the other hand, kept the same DIM Factor of 166 for shippers who pay retail rates. For shippers who pay daily rates, the UPS DIM factor is the same as FedEx: 139.

For example, if you shipped a 10” x 10” x 10” package that weighed 7 pounds with the retail rate, your UPS DIM weight calculation would be (10 x 10 x 10)/166 = 7 pounds. You would be charged for shipping a 7-pound package since the DIM weight is the same as the actual weight. For this package shipped retail, UPS has a DIM weight one pound less than FedEx.

However, ship that same 7-pound item using the daily rates that most business pay, and the UPS DIM factor drops to 139, causing the billed weight to increase to 8 pounds.

UPS DIM Weight Formula

UPS has also changed its base billing rates. Both UPS and FedEx used the same base billing rates in the past. Now, for packages of the same rate, UPS has a small price advantage in Zones 2 through 4. FedEx is a bit cheaper in Zones 5 through 8.


USPS Dimensional Weight in 2020

In 2019, the US Postal Service lowered their DIM Factor from 194 to 166 (the lower the DIM factor, the higher the DIM weight charges). This puts USPS dimensional weight pricing in line with UPS retail DIM pricing.

USPS still has a smaller volumetric weight penalty than most packages sent via UPS or FedEx. For example, a parcel measuring 12 x 12 x 14 would be billed at 15 pounds by both FedEx and UPS daily rates. USPS would bill this same parcel at 13 pounds. (12 x 12 x 14)/166 = 13 pounds.

When shipping with USPS Priority Mail, even packages affected by dimensional weight may not end up costing you more as the shipping party. The final caveat regarding USPS’s dimensional weight calculations is that they are only applied to zones 5 and up! This means that so long as you’re shipping your package relatively close by via USPS, DIM weight shouldn’t be an issue at all! USPS’s official dimensional weight calculator can be found here.


How Order Fulfillment Companies Help Clients Reduce Dimensional Weight Charges

Dimensional weight doesn’t have to drag down your sales, even if your products are large or require extra packaging. When you work with an order fulfillment company or 3PL, their volume pricing discounts can save you (and your customers) on shipping.

Order fulfillment companies ship a large number of packages with the major freight companies, so they are able to negotiate volume discounts that they can pass on to their clients. In addition to a lower rate per pound shipped, some order fulfillment providers also negotiate and pass along more favorable DIM factors to their clients.

With two ways to save on shipping, your order fulfillment company can take the weight off your shoulders when it comes to sending large or bulky items.

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