Dimensional Weight Calculator
How It Works
Dimensional weight (DIM weight) is a pricing technique used by carriers to account for package density. Large, lightweight packages take up more space on trucks and planes, so carriers charge based on whichever is greater: actual weight or dimensional weight.
The formula is simple: DIM Weight = (Length x Width x Height) / DIM Factor. UPS and FedEx use a DIM factor of 139 for domestic shipments, while USPS uses 166. International shipments often use a factor of 139 or lower.
To reduce shipping costs, minimize package dimensions by using right-sized boxes and removing excess void fill. Even reducing each dimension by 1 inch can significantly lower DIM weight. Always round up dimensions to the nearest inch as carriers do.
Frequently Asked Questions
What is the DIM factor for major carriers?
UPS and FedEx use 139 for domestic shipments. USPS uses 166. International shipments typically use 139 for UPS/FedEx. DHL uses 139 for express and varies for other services.
How can I reduce dimensional weight charges?
Use the smallest possible box, minimize void fill, consider flat-rate options for dense items, use poly mailers instead of boxes for soft goods, and consolidate multiple small items into one shipment.
When did carriers start using dimensional weight?
UPS and FedEx introduced DIM weight pricing for ground shipments in 2015 (previously only for air). The change significantly increased shipping costs for lightweight, bulky items. USPS applies DIM weight only to Priority Mail packages over 1 cubic foot.
What is considered an oversize package?
UPS and FedEx classify packages as oversize if the longest side exceeds 48 inches, or if length plus girth (2x width + 2x height) exceeds 130 inches. Packages exceeding 165 inches may not be shippable.