The world of retail isn't all that complicated – as long as your numbers are in order. That's easier said than done, especially if your business sells things all over the world. To keep track of inventory, you're probably using barcodes which are used by everyone from massive e-commerce giants like Amazon to small mom and pop shops. Even the average consumer deals with product barcodes at the grocery store self-checkout. The problem is that most of us don't pay attention to the UPC or EAN numbers attached to the barcodes unless something goes awry.

Everyone working in retail has been there: squinting to see the numbers beneath the barcode because an item won't scan and you have to enter them manually. So what happens when it keeps telling you that it needs a 13- digit EAN but all you have is a 12-digit UPC? Why is the code beneath the barcode registering as incorrect?

What Is A UPC?

Ever look on the back of a product you purchased to see a barcode? That 12-digit number hiding underneath the lines is a Universal Product Code. UPC codes are the original format for product barcode numbers around the world. Unlike an EAN, the country code is left off of the graphic because at the time the UPC was invented, it was thought that most goods sold in the United States and Canada were imported, distributed and manufactured in North America. In that case, there'd be no need to really specify. Many people still consider UPC codes to be safer than EAN codes because older accounting and inventory systems may not be able to scan 13 digits.

What Is An EAN?

A European Article Number (also known as either an EAN-13 or U.P.C. Version A) has 13 digits. That's one more than a traditional UPC. This is because that very first digit is a country code, and it was added as the demand for products increased across Europe, Asia and Australia. In the U.S. and Canada, the country code would be 0.

Convert a UPC To an EAN

Sometimes, in order to scan an item, you'll need to convert a UPC into an EAN. Some newer scanners do this automatically, but others can't. If your scanner can't read a UPC number, simply put a 0 in front of the first number to convert it into an EAN. For example, a 12-digit UPC may be 123456789012. The EAN would be 012345678912. Remember, EAN numbers must be 13 digits.