When Should You Use an EAN-13 vs. a UPC-A?

Traditionally, UPC-A format barcodes were predominantly used in the USA, while EAN-13 format barcodes were the standard for the rest of the world. Today, most modern retail systems globally can process both formats without issue.

However, to ensure a smooth product launch, it is best to match your barcode to your primary market:

• Selling in the USA or Canada: UPC-A barcodes are highly recommended.
• Selling in the Philippines or Internationally: EAN-13 barcodes are the preferred choice.

Our retail barcode packages include both versions.

The Technical Side: Parities and Encoding

To understand why EAN and UPC barcodes are interchangeable, it helps to understand how they are built.

The way a digit is encoded into every barcode is through 7 blocks of either white or black lines making up each digit. A full set of digits (0 through 9) is called a parity. Retail barcodes require a minimum of two parities (one for the left side and one for the right) so they can be scanned upside down and still return the correct number.

• The Original UPC: Created in the 1970s by George Laurer, the 12-digit UPC system uses two different parities: a left-side odd parity and a right-side even parity (each containing 6 digits).
• The EAN-13 Upgrade: Later, the 13-digit EAN-13 system was introduced as a superset of the UPC barcodes. They were deliberately designed to be used in conjunction with UPC-A barcodes. They employ the exact same left-odd and right-even parities but add an additional "left-even" parity.
• The Hidden First Digit: In an EAN-13 barcode, the very first digit is never actually encoded into the printed bars. Instead, it determines how the other digits are encoded.
• Why They Look Identical: In the case of a leading '0', the 0 dictates that all of the initial 6 digits will use the standard left-odd parity. This means the printed bars look exactly the same as a UPC barcode would without the leading '0'.

How Retail Scanners Read Your Barcode

It is important to remember that cash register scanners only read the physical black and white bars. They do not read the human-readable digits printed underneath.

Because an EAN-13 barcode with a '0' on the front looks physically identical to a UPC barcode without the '0', scanners can sometimes get confused. This is largely determined by what the software system is expecting to see.

Often, this confusion occurs if a barcode is scanned before it has been linked to a product in the store's inventory system. The software has no point of reference, so it assumes it is reading a UPC format. Once you officially add your 13-digit number to the retailer's database (usually via their buyer setup form), the system knows what to expect, and your product will scan appropriately as an EAN-13 format barcode every time.