Know what your carrier will bill before you pack.
Enter the box size and weight. You'll see the dimensional weight, the billable weight after rounding up to the next pound, and a cost estimate from your own carrier rates.
Result
Billable weight
0 lb
Three steps from box to bill
Example: a 12 × 10 × 6 in box is 720 cubic inches. With a divisor of 139, its dimensional weight is 720 ÷ 139 = 5.18 lb. If it actually weighs 2.2 lb, you're billed for 6 lb. With the USPS rule, the same box is under 1 cubic foot, so it's billed on actual weight: 3 lb.
Carriers' real charges differ. Rates change by carrier, service, zone and contract, and many add fuel, residential or oversize surcharges. Some carriers round each dimension to the nearest inch first, and packages are often re-measured in transit, so measure the packed box, not the product. Use this as a check, not a quote.
Shipping weight questions
Can't find what you're looking for? Our team replies within one working day.
What is dimensional weight?
Dimensional (DIM) weight is the weight a carrier assigns to a package based on how much space it takes up. A large, light box fills a truck as much as a heavy one, so carriers bill on whichever is higher: the actual weight or the dimensional weight.
Which divisor should I use?
Length × width × height in inches is divided by a number called the DIM divisor. UPS and FedEx commonly use 139 for daily and retail rates, and USPS commonly uses 166 for packages over one cubic foot (1,728 cubic inches). Negotiated contracts and some services use other numbers, and carriers change their rules, so check your carrier's current rules and enter your own divisor if it differs.
Why is the billable weight rounded up?
Carriers bill in whole pounds and round any fraction up. A package that weighs 2.1 lb is billed as 3 lb. That is why a slightly smaller box or lighter packaging can save you a full pound on every label.
Why doesn't this tool show carrier prices?
Rates differ by carrier, service, zone, contract and surcharges, and they change often. Rather than guess, the tool asks for your own rates so the answer matches what you are actually billed.
Does AjVik work out shipping for me?
Yes. You save each product's weight and dimensions once. AjVik uses them for shipping rates at checkout and when you buy labels through Shippo for USPS, UPS and FedEx, and it prints labels in bulk and tracks each shipment.
Buy, print and track every label from one screen.
AjVik buys USPS, UPS and FedEx labels through Shippo using the weights you've already saved. Try it free for 7 days.
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