August 17, 2009 12:03pm by swood | 
I sell stuff on eBay and other sites every so often, and my preferred shipping method is the United States Postal Service via Priority Mail. It’s just so freakin’ convenient when you can print out postage at home and leave the package on your doorstep for pickup. The price is normally reasonable too, until recently.
For a long time now, the USPS has been charging extra for packages that exceed a dimensional total of 84 inches. This is supposed to account for strangely shaped or otherwise awkward packages. Last night I was calculating postage on the USPS website when I ran across a new checkbox…
Is your package greater than 1 cubic foot in volume?
What? That seems pretty restrictive! A package need only be 12 x 12 x 12 inches tall, which is very small. If you check this box, which, I suppose… you must… then you are subject to a new postage calculation formula. One that creates a “virtual weight” for your package! Here’s the formula:
Dimensional Weight
Length x Width x Height = X / 194 = X pound
So let’s say you have a package that measures 20 inches x 12 inches x 6 inches, and weighs 5 pounds. Nope. It doesn’t weight 5 pounds according to the USPS. It weighs…
(20 x 12 x 6) / 194 = 7.4 pounds
And your postage cost goes up dramatically! I was going to ship a package the other day and it came out to $14 with the normal Priority Mail postage calculation. But when I checked the box for Dimensional Weight postage, it jumped to just over $25!
So they lost my business. I went to a UPS store and shipped the same package for $12. So much for convenience.
The new USPS pricing rule is a bit confusing. It is supposed to be applicable if your package exceeds 1cf or 1728 cubic inches. In your specific case a package of 20x12x6 is actually only 1440 cubic inches, so the dimensional pricing does not apply. In general, however, I find that UPS as well as Fed Ex ground shipments are less expensive than priority mail shipments, plus UPS and Fed Ex gives you the first $100 insurance coverage free.
It has been pointed out that the dimensions I randomly picked for my example result in less than 1 square foot of volume. Whoops.