Dimensional weight calculator
Enter package dimensions (length, width, height) to calculate volumetric dimensional weight across major parcel carriers. Switch between Imperial (inches/lbs) and Metric (cm/kg) units, compare carrier divisors (139 for FedEx/UPS domestic, 166 for USPS Priority, 5000/6000 for metric), and enter actual scale weight to determine the billable weight charged by the carrier.
Calculates client-side · No package dimensions are uploaded
Optional comparison
Carrier Divisor (DIM Divisor)
Select a carrier rule or enter a negotiated custom divisor
Exact: 13.81 lbs (billed at rounded integer)
Determined by DIM weight (exceeds 8 lbs scale weight)
Equivalent to ~1.111 cu. ft.
Carrier Comparison for 16 × 12 × 10 in
| Carrier / Standard | Divisor | Exact DIM Weight | Billed DIM Weight | Billable Result |
|---|---|---|---|---|
| FedEx (Standard / Express / Ground)Selected | 139 | 13.81 lbs | 14 lbs | DIM governs (14 lbs) |
| UPS (Daily Rates / Commercial)Selected | 139 | 13.81 lbs | 14 lbs | DIM governs (14 lbs) |
| UPS (Retail / The UPS Store) | 166 | 11.57 lbs | 12 lbs | DIM governs (12 lbs) |
| USPS Priority Mail / Express | 166 | 11.57 lbs | 12 lbs | DIM governs (12 lbs) |
| DHL ExpressSelected | 139 | 13.81 lbs | 14 lbs | DIM governs (14 lbs) |
| IATA Air Cargo / Freight | 166 | 11.57 lbs | 12 lbs | DIM governs (12 lbs) |
Copy dimensions, volume, and dimensional weight breakdown.
Example
Medium box shipped via FedEx Ground
A 16 × 12 × 10 inch package has a volume of 1,920 cubic inches. Using the standard FedEx domestic divisor of 139 yields an exact dimensional weight of 13.81 lbs, billed at 14 lbs. If the scale weight is only 8 lbs, the carrier bills for 14 lbs.
Related: Etsy fee calculator, UK parcel size checker
FAQ
- What is dimensional weight (DIM weight)?
- Dimensional weight (also called volumetric weight) is a pricing technique used by commercial parcel and freight carriers (FedEx, UPS, USPS, DHL) to account for the space a package occupies in a vehicle or aircraft relative to its actual scale weight.
- How is dimensional weight calculated for domestic US shipments?
- Multiply Length × Width × Height in inches to calculate cubic inches. Divide the cubic volume by the carrier's dimensional divisor: standard FedEx, UPS, and DHL domestic divisor is 139; USPS Priority Mail divisor is 166 (for packages over 1 cubic foot).
- How is dimensional weight calculated in the metric system?
- Multiply Length × Width × Height in centimeters to obtain cubic centimeters. Divide by the international standard divisor of 5000 (used by DHL, FedEx International, and UPS) or 6000 for IATA standard air freight to find weight in kilograms.
- What is billable weight?
- Billable weight is the greater of the package's actual scale weight and its dimensional weight. Commercial parcel carriers always charge shipping rates based on the billable weight, rounded up to the nearest whole pound or kilogram.
- Why do different carriers use different DIM divisors?
- Carriers negotiate divisors based on customer shipping volume and transportation modes. A smaller divisor (like 139) results in a higher dimensional weight, whereas a higher divisor (like 166) yields a lower dimensional weight.
- How do I calculate dimensional weight programmatically?
- Compute volume = length * width * height. Compute dimWeight = volume / divisor. Billable weight = actualWeight ? Math.ceil(Math.max(actualWeight, dimWeight)) : Math.ceil(dimWeight).
- How does dimensional weight differ from Royal Mail / UK parcel size bands?
- Domestic UK postal carriers like Royal Mail categorize parcels into fixed physical slots and weight tiers (Letter, Large Letter, Small Parcel, Medium Parcel) with hard outer measurement caps. In contrast, international couriers (DHL, FedEx, UPS) and air freight calculate volumetric weight by dividing total cubic volume by a divisor (such as 5000 or 139), billing whichever is greater between physical scale weight and dimensional weight.
- What happens if a package exceeds both dimensional weight and carrier maximum size limits?
- In addition to charging for volumetric weight, couriers impose additional handling surcharges, oversize fees, or peak season surcharges if any single dimension exceeds maximum conveyor limits (commonly 48 inches or 120 cm, or length plus girth exceeding 108–130 inches). Packages exceeding maximum weight (typically 70 lbs or 31.5 kg for standard parcel networks) must be routed to freight or pallet services.