One divisor: 139
FedEx uses 139 in³/lb for U.S., Puerto Rico and international shipments in your own packaging. There is no smaller-package exemption: DIM weight is figured on every package.
FedEx Service Guide 2026FedEx dimensional weight calculator
FedEx divides a package's volume by 139 to get its dimensional weight, and bills the greater of that and the actual weight. Enter the packed size and weight to see the billable weight, with each step shown. For all five carriers at once, use the dimensional weight calculator.
Your package
in
in
in
lb
Fractions work: 27½ or 3-1/8. Results update as you type.
Billable weight at FedExEstimate
– lb
Threshold meter
Estimate only. FedEx's measurement governs billing. Weight only, never a price.
Dispute evidence checklist
If the carrier's bill differs from this estimate, gather this evidence before you dispute:
- Photo of the packed box or pallet with a tape measure across each side
- Photo of the package on a scale showing the weight
- The label or bill of lading copy with the dimensions and weight you entered
- The carrier's adjustment notice with the recorded dimensions
- A screenshot or printout of this result, with the date
- Photos of all six sides if the carrier claims damage or a nonrectangular shape
- Your scale and tape calibration notes, if you have them
How we got there
The FedEx rules behind this result
Fractions round up
Since August 18, 2025, any fraction of an inch rounds up to the next whole inch before the volume is figured, and the DIM weight rounds up to the next whole pound.
FedEx Service Guide 2026, dimensional weightOversize lines
Additional Handling applies past size lines including a longest side over 48 in, with a 40 lb minimum billable weight. Length plus girth over 130 in is Oversize, with a 90 lb minimum billable weight.
FedEx Service Guide 2026Other carriers
The same package can bill differently somewhere else. The dimensional weight calculator compares all five side by side, and the divisors dataset lists every rule in one table.
Questions
What divisor does FedEx use?
139 cubic inches per pound, for U.S., Puerto Rico and international shipments. In metric, FedEx Express uses 5,000 cm³ per kilogram.
Does FedEx round dimensions up or to the nearest inch?
Up. The FedEx Service Guide 2026 states that any fraction of an inch is rounded up to the next-higher inch, a rule in effect since August 18, 2025. Older pages that teach rounding to the nearest inch are out of date.
How long do I have to dispute a FedEx adjustment?
For FedEx Express, an invoice adjustment for an overcharge must reach FedEx within 60 days after the original invoice date. For FedEx Ground, the tariff allows 180 days after the date of shipment. Both run through FedEx Billing Online.
Sources
- FedEx Service Guide 2026 (effective January 5, 2026), dimensional weight and invoice adjustment sections
- FedEx Ground tariff, invoice adjustments and overcharges
Rules last checked November 12, 2026 · How we check every figure