“What is the default product weight unit in Magento?”
One of the questions we are asked by Magento clients all the time is what the weight setting in Magento represents. Is it ounces, pounds, kilograms? The common answer you will see online is that the Magento weight unit is whatever you want it to be as specified in your Magento shipping service setup. That’s technically correct but doesn’t help you much if you need an answer and are stuck with shipping rate issues that are due to misconfigured Magento product weights.
What you need to know is the Magento weight entry field uses a 10 digit decimal system and if you are in the US you are using ounces which is a 16 digit system. That means you can’t always enter ounces into your Magento weight field. Sure entering 1 into the Magento product weight field will get you a pound, but what should you enter for your 7oz product? That would be 0.44! All you need to do is to translate that with a formula. You can do this by multiplying your product’s weight in ounces by 0.0625 to derive the decimal equivalent and round as you see fit.
The chart below is a quick reference for converting ounces to decimals for Magento product weights. In case this doesn’t cover all your needs, you can also use the handy Magento weight calculator to figure our your Magento weights.