Home / Data tools / DIM divisor
Dimensional weight calculator: DIM divisor 139 vs 166
Compare how DIM divisors such as 139 and 166 affect the billable weight of a package.
Source: Standard published dimensional divisors · Divisors as published by the carriers; prices from FedEx Standard List Rates, effective January 5, 2026 · Free, no signup
| Divisor | Dimensional weight | Billable weight | What governs | Published rate, zone 5 |
|---|---|---|---|---|
| 139 | 22 lb | 22 lb | dim | $28.28 |
| 166 | 19 lb | 19 lb | dim | $26.42 |
| 194 | 16 lb | 16 lb | dim | $23.41 |
| 250 | 13 lb | 13 lb | dim | $21.69 |
This box is billed at 22 lb under divisor 139, so dimensional weight applies until the package actually weighs more than 22 lb. Below that, you are paying for empty space. The divisor is a negotiated term. Moving from 139 to 166 is a real request to make, and it applies to every package large enough to be dimensioned, not just one lane or service. Rates shown are FedEx published Ground list rates before any discount, fuel or accessorials.
Get a free estimate of your savings.
A first estimate of what dimensional weight costs on a package profile like yours, and what a better divisor would be worth.
- A first estimate within one business day: what better terms and accurate billing would be worth to you, and where it would come from.
- Built from what you tell us: your carriers and spend band, priced against the published 2026 rates and surcharges our tools run on.
- Nothing to upload: we ask for a copy of your agreement only if you want the full review.
What is dim divisor?
A dimensional divisor turns package volume into a billable weight: length times width times height, divided by the divisor. Carriers bill the greater of actual and dimensional weight. A lower divisor gives a higher billable weight, so moving from 166 to 139 raises the calculated weight of every dimensioned package by about 19% before rounding, with no change to the rate card.
Worked example
An 18 by 14 by 12 inch box is 3,024 cubic inches. Divided by 139 that is 22 lb, and by 166 it is 19 lb, so a 6 lb packed carton is billed as 22 lb or 19 lb. At zone 5 list rates that is $28.28 against $26.42, where the actual 6 lb would list at $18.60. Packed in a 16 by 12 by 10 inch box instead, it bills at 14 lb and $22.23 on the standard 139.
Published rates, not your agreement
The calculator applies the standard formula and prices the result at FedEx Ground list rates before any incentive. It does not apply your incentive, the minimum billable weights for additional handling and oversize packages, or USPS rules for packages under one cubic foot. It shows one package; the annual cost depends on how many of your packages are dimensioned.
Source: Standard published dimensional divisors. Divisors as published by the carriers; prices from FedEx Standard List Rates, effective January 5, 2026.
Read more
- Dimensional weight explained
- UPS and FedEx dimensional weight history
- USPS dimensional pricing change, July 2026
When the published answer is not enough: Carrier contract negotiation or Shipping analytics.
Other tools
Review the terms behind your shipping costs.
We negotiate carrier agreements and check invoices against them. Our fees are based on recovery or documented savings, and the initial review is free.
Or call 888-356-4421
Free, and no obligation. A written evaluation back inside 48 hours. No fee unless we find documented savings. How we handle your documents
- Your current agreement, any carrier
- One recent invoice, if you have one
- A written evaluation back inside 48 hours