Dimensional Weight Calculator — Shipping DIM Weight
Enter your parcel length, width, height and actual weight — see the dimensional weight and which is higher (the billable weight the carrier charges).
Unit system
cm
cm
cm
kg
DIM weight exceeds actual weight — carrier charges DIM weight
4.8 kg
DIM weight- 1
Package volume
40 × 30 × 20 = 24,000 - 2
DIM weight
24,000 ÷ 5,000 = 4.8 - 3
Billable weight
max(3, 4.8) = 4.80DIM weight exceeds actual — carrier bills DIM weight.
How does this calculator work?
DIM weight = L × W × H ÷ DIM factor (5000 for metric cm/kg, 139 for US inches/lb). Carriers charge the larger of DIM weight vs actual weight. Large light packages almost always trigger DIM billing — right-size your box to avoid paying for air.
Formula
How this is calculated
Carriers like UPS, FedEx and DHL charge based on whichever is greater — the actual weight or the dimensional (DIM) weight — to account for the fact that large light packages take up space worth more than their weight in freight charges. The DIM weight converts volume into a weight-equivalent by dividing the total cubic measurement by a carrier-specific DIM factor.
For metric shipments (cm/kg) the standard DIM factor is 5000, derived from the IATA standard for air freight: 1 kg = 6000 cm³ was an older standard, while most couriers now use 5000. In the US domestic market, UPS and FedEx use 139 (cubic inches per pound). Some carriers have moved to 4000 (metric) for domestic parcels — check your carrier's current rate card, since DIM factors changed significantly in the 2010s and may vary by zone or service level.
The calculator compares DIM weight against actual weight and highlights which is billable. A box that is large but nearly empty will almost always be billed at DIM weight. Reducing any one dimension — for example switching to a tighter-fitting box — cuts volume and therefore DIM weight proportionally.
Frequently asked questions
For metric (cm/kg): most international couriers use 5000 (some domestic carriers use 4000). For US domestic in inches/lb: UPS and FedEx use 139. Always verify with your carrier's published rate card as these figures are updated periodically.
Whenever the DIM weight (L × W × H ÷ DIM factor) is greater than the actual weight on the scale. Bulky, lightweight items — pillows, electronics in large boxes, furniture — typically trigger DIM billing.
Use the smallest box that safely fits the contents. Every reduction in any dimension directly reduces volume and DIM weight. Removing excessive void fill that forces a larger box also helps — but never compromise packaging integrity.
TG we-Calculate Editorial Team. (2026). Dimensional Weight Calculator — Shipping DIM Weight [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/dimensional-weight-calculator
TG we-Calculate Editorial Team. "Dimensional Weight Calculator — Shipping DIM Weight." TG we-Calculate. 2026. https://we-calculate.com/calculator/dimensional-weight-calculator.
TG we-Calculate Editorial Team, "Dimensional Weight Calculator — Shipping DIM Weight," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/dimensional-weight-calculator
@misc{wecalculate_dimensional_weight_calculator, title = {Dimensional Weight Calculator — Shipping DIM Weight}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/dimensional-weight-calculator}}, year = {2026}, note = {TG we-Calculate} }
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