Free Tool
Dimensional Weight Calculator
Calculate dimensional weight for FedEx, UPS, and USPS shipments. See whether your package will be billed by actual weight or dimensional weight, and what your billable weight is.
How to use: Enter your package dimensions and actual weight. The calculator compares actual weight to dimensional weight for FedEx, UPS, and USPS, and shows which one the carrier will bill.
How dimensional weight works
Dimensional weight is a pricing method that accounts for package size, not just actual weight. Carriers use it because a large, lightweight box takes up valuable truck space that could be used for heavier, denser freight. The formula is simple: multiply length x width x height in inches, then divide by the carrier's dim factor.
The carrier then compares the dimensional weight to the actual weight and charges whichever is higher. This is your billable weight. If your package is large but light, you will likely be billed at the dimensional weight — which can be significantly more than the actual weight.
Dim factors by carrier
FedEx and UPS both use a dim factor of 139 for domestic shipments. This means every 139 cubic inches equals 1 pound of dimensional weight. USPS uses a more generous factor of 166, meaning packages need to be larger before dim weight kicks in. International shipments often use a lower factor of 139 or even 127, increasing dimensional weight charges.
Warp does not use dimensional weight
Warp prices freight by the pallet. There is no dim weight calculation, no dim factor, and no billable weight adjustment. You get a flat per-pallet rate that includes pickup, cross-dock handling, line haul, and delivery. For shippers moving freight that consistently gets hit with dim weight charges from parcel carriers, switching to Warp pallet pricing often reduces cost significantly.
Dimensional weight FAQ
What is dimensional weight?
Dimensional weight (DIM weight) is a pricing technique used by carriers to account for package size, not just weight. It is calculated by multiplying length x width x height (in inches) and dividing by a dim factor (typically 139 for FedEx and UPS, 166 for USPS). The carrier charges the higher of actual weight or dim weight.
What is a dim factor?
The dim factor (also called dimensional divisor) is the number you divide cubic inches by to get dimensional weight. FedEx and UPS use 139 for domestic shipments. USPS uses 166. A lower dim factor means dimensional weight is calculated higher.
How do I avoid dim weight charges?
Reduce package size to match the product as closely as possible. Eliminate excess void fill and use right-sized boxes. For freight shipments, consider Warp per-pallet pricing which does not use dimensional weight calculations.
Skip the dim weight math
Warp quotes by pallet with all-inclusive pricing. No dim weight calculations, no billable weight surprises.