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Calculator Daily

Dimensional Weight Calculator

Compare a packed parcel’s actual weight with its dimensional weight, using the divisor and rounding rules you choose.

Changing setup converts measurements and reloads its example divisor and rounding settings.

Use a decimal point, without commas or units. Dimensions: equivalent of 0.000001 to 1,000,000 cm; weight: equivalent of 0.000001 to 1,000,000 kg. Divisor: 0.000001 to 1,000,000 in the displayed units.

Finished outside dimensions (cm)

Include the box and all packing material.

Editable example rule. Use the divisor for your actual service.

Rounding settings

Example settings loaded. Confirm your carrier’s divisor and rounding rules.

Which weight controls?

Enter three outside dimensions, the actual packed weight, and a positive divisor. The comparison updates automatically.

A light parcel can take up enough space to be charged at a higher weight. This calculator compares actual packed weight with dimensional weight under the rule you enter. It shows the measurements, divisor, and rounding behind the estimate so you can check them against your service terms.

How to use your parcel measurements

  1. Measure the closed, packed parcel’s outside length, width, and height, and weigh the entire parcel.
  2. Choose the unit setup, enter your service’s divisor, and check both rounding settings. The initial settings are examples.
  3. Read the controlling weight and check the displayed arithmetic. Confirm whether your service applies any eligibility threshold or other exception.

How dimensional weight is calculated

Dimensional weight = rated length × rated width × rated height ÷ divisor. The divisor must match the dimension and weight units: cm³/kg or in³/lb. The calculator first applies your dimension rounding, then divides the volume by the divisor.

Next, it rounds the dimensional and actual weights upward by the selected weight increment and takes the greater result. With no weight rounding, it compares their unrounded values. An exact increment stays at that increment. Display values use up to four decimal places (scientific notation for very small or large results); the comparison uses the underlying values.

Two worked examples

A large, light parcel

A parcel measures 40 × 30 × 20 cm and weighs 3.2 kg. Under an illustrative divisor of 5000 and upward 0.5 kg weight rounding, dimensional weight is 24,000 ÷ 5000 = 4.8 kg, rounded to 5 kg. Actual weight rounds to 3.5 kg. The estimate is 5 kg.

Why dimension rounding matters

A 12.1 × 8.2 × 6.3 inch parcel weighs 3 lb. With divisor 139, rounding each dimension up gives 13 × 9 × 7 = 819 in³. Dimensional weight is about 5.8921 lb, rounded up to 6 lb. Using the entered dimensions gives 625.086 ÷ 139 ≈ 4.4970 lb, rounded up to 5 lb. Confirm the dimension rule before using either answer.

Use the rule for your actual service

Divisors, dimension rounding, weight increments, and eligibility can differ by service, country, account, and date. The example divisors 5000 and 139 are not mathematically identical unit conversions. Changing the setup converts measurements and loads the other setup’s example rules; check them again.

Use this calculator for a rectangular parcel. Special shapes and service thresholds need the carrier’s own method. A weight estimate alone does not determine the shipping price.

Frequently asked questions

Is this a carrier price quote?
No. It compares weights under the settings you choose. Service eligibility thresholds, minimum billable weights, surcharges, special shapes, and negotiated terms are not modeled. Confirm the rule and get the actual price from your carrier.
Which divisor should I use?
Use the divisor stated for your carrier, service, country, and account. The initial 5000 cm³/kg and 139 in³/lb settings are examples. They are not exact unit conversions of each other.
Should I measure the inside of the box?
Use the finished parcel’s outside dimensions, including any bulging or protrusions. Actual weight must include the box, item, tape, filler, and other packing materials.
Why can a light parcel have a higher billable weight?
Dimensional weight assigns a weight to the space a parcel occupies. When that rounded weight exceeds the rounded actual packed weight, it controls this estimate.
What happens when I change the calculation setup?
The tool converts your entered dimensions and actual weight. It then loads that setup’s example divisor and rounding settings. Check the visible settings again before using the estimate.

Carrier guidance to check

Read the terms for the exact service you plan to use. These official pages illustrate why a divisor and rounding rule must be specified: UPS Philippines dimensions and weight and FedEx Australia dimensional-weight guidance.

Choose a box before comparing shipping weight

Use the Shipping Box Fit Calculator to check a box you have, or the Shipping Box Size Calculator to find minimum inside dimensions. This calculator needs the finished outside measurements instead.