Dimensional Weight Calculator

Dimensional weight = (L × W × H) / Divisor
Billable weight = the greater of Actual weight and Dimensional weight

• L, W, Houtside dimensions of the packed box, each rounded to the nearest whole unit
• Divisorcarrier and service specific: 139 in³ per lb for FedEx and UPS US domestic, 166 for their international services, 194 for USPS, 5000 cm³ per kg for the metric convention
• Billable weightthe figure the rate table is actually read against, rounded up to the next whole unit

• The divisor is a contract term, not a constant. FedEx and UPS moved US domestic retail from 166 to 139 in 2017, raising the dimensional weight of every box by 19% overnight. Negotiated accounts frequently keep a higher divisor, and that one number is often worth more than a headline percentage discount on the rate card.
• Measure the box as it will actually travel, at its widest point, including bulge, tape and any overhang. Carriers re-measure on the belt with automated dimensioners, and a billing adjustment issued weeks later costs more than packing it properly did.
• Dropping one box size usually beats negotiating. Cutting the example from 18 × 14 × 12 to 16 × 12 × 10 gives 1,920 in³, a dimensional weight of 14 lb rather than 22, on the same 9 lb of contents.
• The imperial and metric conventions describe nearly the same density: 139 in³ per lb works out to about 5,022 cm³ per kg, so 139 and 5000 are close enough to compare directly. A 6000 divisor, offered on some economy and air-freight services, is the one that is genuinely cheaper.