USPS Dimensional Weight Calculator

I run a small toy company in Boise, ID, shipping oversized but lightweight items like plush animals and inflatable toys. I assumed USPS only charged by actual weight, so I was blindsided when Priority Mail packages over a certain size started getting billed on dimensional weight instead.

https://dimmath.com/dim-wei ...


My plush animal boxes were light as a feather but apparently "large" enough to trigger a different pricing rule I didn't know existed. I use DimMath dimensional weight calculator to check whether a box crosses USPS's dimensional weight threshold before I ship it. Now I know in advance which of my products will get DIM-priced and which won't, so I can size boxes to stay under the threshold where it makes sense. That one insight alone cut my average USPS cost per plush shipment noticeably.