Dimensional Weight Calculator
Calculate volumetric weight for a parcel and find out which weight the courier will charge.
Last updated · View algorithm, constants and default inputs (JSON)
About this calculator
This is a planning estimate: dimensional weight = package volume ÷ divisor, then chargeable weight is the greater of dimensional and actual weight. For U.S. parcel examples, 139 is used by FedEx and UPS Daily Rates, while UPS Retail Rates use 166; 5,000 is a common cm³/kg divisor. The applicable divisor, dimension rounding, billable-weight rounding and surcharges depend on carrier, service, route and account. Confirm the current shipment quote.
Worked example
calculated with the default values below
Package length 20 in · Package width 16 in · Package height 12 in · Actual weight 5 lb · Carrier divisor 139 — FedEx U.S. and UPS Daily Rates examples · Dimension unit Inches and pounds Volume 3,840.0 in³ · Dimensional weight 27.63 lb · Chargeable weight 27.63 lb · Charged on Dimensional weight — the parcel is bulky · Difference between actual and dimensional 22.63 lb · Cost increase from dimensional weight 5.53 x
General background references
Disclaimer
These calculators provide planning estimates only. Building codes, wiring regulations and safety requirements differ by country and change over time, and nothing here replaces a licensed professional or a permit. For structural, electrical or gas work, follow local code and have the installation inspected.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
u ∈ {cm, in}; k = {2.20462, u = cm ∨ d ≥ 1000; 1, u = in ∧ d < 1000}; Q = max(A, L × W × H ÷ d × k)
- L
- length
- W
- width
- H
- height
- d
- carrier divisor
- u
- dimension unit, cm or in
- A
- actual weight
- k
- kg-to-lb conversion factor
- Q
- chargeable weight
For inches: L×W×H÷divisor gives lb. For cm with divisor 5000: L×W×H÷5000 gives kg, converted to lb by ×2.20462. Chargeable estimate = max(actual, dimensional); carrier rules vary.
Frequently asked questions
How is dimensional weight calculated?
For inch inputs, volume in cubic inches is divided by the selected divisor to estimate pounds. For centimeter inputs, cubic centimeters are divided by 5000 to estimate kilograms and then converted to pounds. The chargeable estimate is the greater of dimensional and actual weight. Carrier rules and divisors vary; check the service you plan to use.