⌕Shipping & logistics
Estimate billable weight from package dimensions and a divisor.
Enter your numbers to see the answer.
Dimensional weight calculator guide
Dimensional weight, also called DIM or volumetric weight, estimates what a large lightweight package costs to ship based on the space it occupies. The calculation multiplies the outside length, width, and height to find package volume, then divides that volume by a carrier divisor. The divisor is not universal: it depends on the carrier, service, route, and agreement, so use the value from the rate rule you are checking. This calculator returns the dimensional-weight estimate; a carrier may compare it with actual scale weight, apply rounding, use minimum billable weights, or calculate each package in a shipment separately. Measure the finished outside carton, including packaging. If you reduce empty space or choose a tighter box, the volume falls and the DIM weight can fall with it. Treat the result as a planning number and confirm the carrier’s current tariff before buying a label or quoting a customer.
Dimensional weight (lb) = length (in) × width (in) × height (in) ÷ carrier divisor. A carrier’s billable weight is often the greater of actual weight and applicable DIM weight, subject to its rounding rule.
Worked example: a carton measuring 40 in × 30 in × 25 in has 40 × 30 × 25 = 30,000 in³ of volume. With a divisor of 139, dimensional weight is 30,000 ÷ 139 = 215.83 lb. If the carrier rounds up to whole pounds, that becomes 216 lb for the DIM comparison. The actual billable weight still depends on the package’s scale weight and the carrier rule.
This calculator uses inches and a divisor that produces pounds. Do not enter centimeters with an inch-based divisor. If a carrier gives a metric rule, convert dimensions and use the divisor supplied for that metric service instead of reusing 139.
Good to know: use outside packed dimensions, not the product dimensions. Check whether the carrier rounds each dimension before multiplying, rounds the final DIM weight, or applies a minimum. The calculator cannot know account-specific rules or special handling charges.
Results are planning estimates. Check the units, product coverage, carrier rules, or local rates before making a purchase or financial decision.
How it works
Estimate billable weight from package dimensions and a divisor. This tool explains the calculation so you can adjust the assumptions to match your situation.
Common questions
Dimensional weight is a shipping estimate based on package volume. It helps carriers price large, light boxes that take up more space than their scale weight suggests.
Multiply the package length, width, and height, then divide by the carrier’s dimensional divisor. With inches and divisor 139, the result is expressed in pounds.
Not always. Billable weight often uses the greater of actual scale weight and dimensional weight, then applies the carrier’s rounding and minimum rules.
Use the divisor in the carrier or service rule you are pricing. Common parcel, freight, and air services can use different divisors, and contracts may override a published default.
The quote may round dimensions, use a different divisor, apply minimums, price each package separately, or include fees and surcharges. Compare the rule details, not just the final number.