How to Use the Dimensional Weight Calculator
Shipping a large but lightweight box can cost more than you'd expect from its actual weight alone. UPS, FedEx, and most other carriers bill domestic shipments based on whichever is greater: actual weight or dimensional (DIM) weight. This calculator uses your box dimensions in inches to find the dimensional weight and compares it to the actual weight to determine your billed weight.
The standard domestic formula is: dimensional weight (lb) = (length ร width ร height in inches) รท 139, and billed weight = the greater of actual weight or dimensional weight. For example, a 16ร12ร8 in box weighing 6 lb has a dimensional weight of about 11 lb โ so it would be billed at 11 lb instead of its actual 6 lb.
Reducing box size or eliminating unnecessary empty space is the most effective way to lower dimensional weight. Keep in mind that 139 is the standard UPS/FedEx domestic divisor for inches and pounds, but some services and international shipments use a different divisor, so it's worth checking your specific carrier's current rate rules before shipping.
Frequently Asked Questions
Carriers like UPS and FedEx bill you based on whichever is greater: actual weight or dimensional weight. A large, lightweight box can end up costing more than its actual weight would suggest.
139 is the standard domestic divisor used by UPS and FedEx for inches/pounds. International shipments and some services use different divisors, so check your carrier's current rate rules for the exact figure.