DIM Factor
Also known as: Dimensional Factor, DIM Divisor, Volumetric Divisor
Definition
The DIM factor (dimensional factor) is the number you divide a package’s cubic size by to calculate its dimensional weight. A lower DIM factor means higher calculated weight and higher shipping costs for the same package size.
DIM Factor Formula
Dimensional Weight = (L × W × H) ÷ DIM Factor
Where:
- L = Length in inches
- W = Width in inches
- H = Height in inches
- DIM Factor = Carrier’s divisor
Carrier DIM Factors
| Carrier | Standard DIM Factor | Notes |
|---|---|---|
| USPS | 166 | Most services |
| UPS | 139 | All services |
| FedEx | 139 | All services |
| DHL | 139 | Express |
| Regional carriers | 166-200 | Varies |
Lower number = higher calculated weight = higher cost
DIM Factor Impact Example
Package: 20" × 16" × 12" = 3,840 cubic inches
| DIM Factor | Calculated Weight | Impact |
|---|---|---|
| 139 | 27.6 lbs → 28 lbs | Higher cost |
| 166 | 23.1 lbs → 24 lbs | Medium cost |
| 200 | 19.2 lbs → 20 lbs | Lower cost |
If actual weight is 5 lbs, you pay for the dimensional weight.
History of DIM Factors
Timeline:
- Pre-2007: DIM factor 194 (UPS/FedEx)
- 2007: Reduced to 166
- 2015: UPS/FedEx reduced to 139
- Currently: 139 is standard for major carriers
The trend toward lower DIM factors increases costs for shippers of large, light items.
Negotiating DIM Factor
Who Can Negotiate
- High-volume shippers
- Businesses with consistent shipping
- Those with large, light products
What to Ask For
- Higher DIM factor (166, 194, or even no DIM)
- DIM factor matching USPS (166)
- Service-specific DIM factors
- Product category exemptions
Negotiation Tips
- Know your average DIM impact
- Calculate savings at different factors
- Present as alternative to base rate discount
- Compare to USPS as benchmark
- Offer volume commitments
DIM Factor by Service Type
Some carriers use different factors by service:
| Service Type | Typical Factor |
|---|---|
| Ground | 139 |
| Air Express | 139 |
| Freight/LTL | Various |
| Parcel Select | 166 |
Minimizing DIM Weight Impact
Packaging Strategies
- Use smallest box that fits
- Reduce void fill
- Consider poly mailers
- Flat-pack when possible
Product Strategies
- Compress products
- Ship disassembled
- Remove bulky packaging
- Use lightweight materials
Carrier Strategies
- Use USPS for large, light items
- Negotiate higher DIM factor
- Use regional carriers
- Consider cubic pricing alternatives
Cubic Pricing Alternative
USPS offers cubic pricing that ignores weight entirely:
USPS Cubic:
- Based on cubic feet (not DIM)
- Up to 20 lbs
- Great for heavy, small items
- Commercial pricing required
When cubic beats DIM:
- Dense products
- Small but heavy items
- Regional shipping
DIM Factor Calculations
Quick reference for common factors:
| Package Size | Factor 139 | Factor 166 |
|---|---|---|
| 12×10×8 (960 ci) | 7 lbs | 6 lbs |
| 18×12×10 (2160 ci) | 16 lbs | 13 lbs |
| 24×18×12 (5184 ci) | 38 lbs | 32 lbs |
| 36×24×18 (15552 ci) | 112 lbs | 94 lbs |
ci = cubic inches