Shipping & Freight Calculators
Dimensional Weight Calculator
Carriers bill the greater of actual weight and dimensional (DIM) weight. Enter package dimensions and choose a carrier divisor to find the DIM weight and the billable chargeable weight.
Last updated: June 2026
Formula Used
DIM Weight (kg) = L(cm) × W(cm) × H(cm) ÷ divisor_cm
Chargeable Weight = max(Actual Weight, DIM Weight)
Common divisors: FedEx/UPS domestic = 139 in³/lb (5,000 cm³/kg); DHL Express = 5,000 cm³/kg; USPS Priority = 166 in³/lb; IATA air freight = 6,000 cm³/kg.
Example Calculation
12×10×8 in box, 3 lb actual, FedEx (divisor 139): DIM = 6.9 lb. Chargeable = max(3, 6.9) = 6.9 lb. Tip: reducing box size by 2 in on each dimension cuts DIM weight by ~40%.
How to Use This Calculator
- Select in/lb or cm/kg units.
- Enter L × W × H of the package.
- Enter actual (scale) weight.
- Choose a carrier preset or enter a custom divisor.
- Read DIM weight and chargeable weight.
Carrier DIM Divisors (2025)
| Carrier | Divisor (in³/lb) | Divisor (cm³/kg) | Notes |
|---|---|---|---|
| FedEx (domestic US) | 139 | 5,000 | All packages since 2015 |
| UPS (domestic US) | 139 | 5,000 | Same as FedEx domestic |
| DHL Express | 139 | 5,000 | Global express standard |
| USPS Priority Mail | 166 | 6,000 | Only Priority; First-Class not affected |
| IATA air freight | — | 6,000 | 1 kg = 6,000 cm³ standard |
Notes & Limitations
Divisors change periodically — verify on your carrier's official pricing page. See also: Shipping Volume Calculator · Customs Duty Estimator.
Frequently Asked Questions
What is dimensional weight (DIM weight)?
DIM weight is a pricing technique where carriers compare the actual weight to the dimensional weight and charge for whichever is higher. This prevents undercharging for large, light packages.
How do I calculate DIM weight for FedEx or UPS?
For FedEx/UPS domestic: L × W × H (inches) ÷ 139, rounded up. Example: 12×8×6 in = 576 ÷ 139 = 4.14 → 5 lb DIM weight. If actual weight is 3 lb, you are billed for 5 lb.
Can I reduce my DIM weight?
Yes — use the smallest box that safely fits your item. Reducing a 12×10×8 in box to 10×8×6 in cuts DIM weight by 52%. Use right-sized packaging and avoid excess void fill.
What divisor does DHL use for DIM weight?
DHL Express uses a divisor of 5,000 cm³/kg (139 in³/lb) for international express shipments, the same as FedEx and UPS.
Does USPS charge dimensional weight?
USPS applies DIM weight only to Priority Mail packages exceeding 1 cubic foot, using a divisor of 166. USPS First-Class and Ground Advantage charge by actual weight only.
What is the difference between DIM weight and CBM?
CBM is the volume in cubic meters, used for sea freight pricing. DIM weight converts volume to an equivalent weight using a carrier-specific divisor. CBM is volume; DIM weight is a weight-equivalent of that volume.