UPS Dimensional Weight Calculator
Calculate UPS dimensional weight using the 139 in³/lb daily-rate divisor (5000 cm³/kg international), then compare it against actual weight to find the chargeable weight.
How UPS dimensional weight works
UPS charges on the greater of actual and dimensional weight. Dimensional weight turns the volume of a parcel into a billable figure with a fixed divisor:
DIM weight = (L × W × H) ÷ divisor
For U.S. daily-rate shipments UPS uses 139 in³/lb; international parcels use the metric 5000 cm³/kg divisor. Round each side to the nearest whole inch, multiply, divide by 139, and round the answer up to the next whole pound.
Worked example (page defaults)
Using the default 20 × 15 × 10 in carton:
- Cubic size: 20 × 15 × 10 = 3,000 in³
- DIM weight: 3,000 ÷ 139 = 21.58, rounded up to 22 lb
If that box actually scales at 16 lb, UPS bills the 22 lb dimensional weight because it is the larger of the two. Measured metrically (about 48,450 cm³) and divided by 5000, the international figure is roughly 9.7, rounding to 10 kg.
Divisor reference
| Carrier / service | Divisor | Unit |
|---|---|---|
| UPS US daily rate | 139 | in³/lb |
| UPS international | 5000 | cm³/kg |
| FedEx US domestic | 139 | in³/lb |
| USPS (over 1 ft³) | 166 | in³/lb |
| Air freight (IATA) | 6000 | cm³/kg |
UPS and FedEx share the same 139 domestic divisor, so a given box returns the same dimensional weight on both. The number only diverges from USPS, which uses the more forgiving 166 divisor and therefore yields a lower dimensional weight for the same carton.
Where the savings are
Since the divisor is fixed, only the box volume is in your control. Eliminate slack fill, downsize to a box that hugs the contents, and re-measure after packing, the longest protrusion counts. To watch actual and dimensional weight resolve into one chargeable figure, use the chargeable weight calculator. The FedEx dimensional weight calculator shares this 139 divisor, while the USPS dimensional weight calculator shows how a 166 divisor changes the result. The base dimensional weight calculator lets you switch between them.