Difference Between EAN-13 and UPC-A Barcodes
UPC-A Barcodes are in effect a subset of EAN-13 Barcodes. If the first digit on the EAN-13 number is a ‘0’, then the bars will be of both the EAN-13 and the UPC-A (without the leading ‘0’) will be identical. The displacement of the human readable numbers below differ between the UPC-A and EAN-13 barcodes however, this is the biggest difference. Both barcodes can be scanned by the majority of scanners easily.
When Should You Use an EAN-13 vs a UPC-A?
UPC-A Format barcodes have traditionally been used in the USA, whereas EAN-13 format barcodes have been used throughout the rest of the world. Nowadays, the majority of stores throughout the world accept barcodes in either format. However, there may be some older systems that will only accept one format or the other. This means that if your product is being sold in the USA, the UPC-A format barcodes are best, however if your product is international, or sold in a country other than the USA, an EAN-13 Barcode is best.
If you come across a store that has difficulty reading your EAN-13 or UPC-A Barcode, they can either ignore the leading ‘0’ or add a leading ‘0’ depending on how many digits their system prefers. If this is done, the barcode will read exactly the same as the opposite format (as the bars are identical regardless), and will still be completely unique.
Both UPC and EAN-13 numbers can be purchased from here. – If you require a UPC-A format barcode, please specify this in the additional information section when you are going to check out.
Why does this occur?
The way a digit is encoded into every barcode is 7 blocks of either white or black making up each digit. – A full set of digits 0-9 is called a parity. – Retail barcodes have a minimum of 2 parities one for the left side and one for the right. – This is so they can be scanned upside down and still return the correct number the right way around.
Originally the 12 digit UPC system was created in the 1970’s by George Laurer. – these work with 2 different parities – a left side odd parity and a right side even parity (each with 6 digits) – the parities for these can be seen in the attached.
Later, a 13 digit EAN-13 system was introduced as a superset of the UPC barcodes. These were deliberately designed to be used in conjunction with UPC-A barcodes. And hence, employed both the left odd parity and the right even parity of the UPC barcodes, but added an additional parity (a left-even parity) which was to be used on a selection of the left hand side digits –
The left and right hand side of the EAN-13 barcodes are still divided into 6 digits each. So the initial digit determines which combination of the first 6 digits will use the newly created left even parity. Hence, in no EAN-13 barcode is the first digit encoded in the barcode, however it does determine the way the other digits are encoded.
– In the case of a leading ‘0’ as with our barcodes, the 0 determines that all of the initial 6 digits will use the left odd parity, meaning that the bars look the same as a UPC barcode would without the leading ‘0’ – As the UPC version also only uses the odd parity.
How do they scan?
Because the actual bars are the only part of the barcode that is scanned (i.e the scanner isn’t reading the digits below the barcode), an EAN-13 barcode with a ‘0’ on the front can sometimes be confused by scanners as a UPC barcode without the ‘0’ and vice-versa. This is largely to do with what the scanner or software system is expecting to see. Often times this occurs when a barcode that is not linked on the system is scanned – The software has no point of reference for what format the barcode should be, and, hence, assumes that it is UPC format. When the number is first added to the system in the 13 digit format and linked to the product in the system (this is generally how stores add the barcodes based on the information provided on their buyer form), it tends to scan appropriately as an EAN-13 format barcode.
Very few stores have had issues with this in the past. And when issues occur, they are generally resolved easily. If you are going in the Musgraves in Ireland, they prefer that you fill out your barcode in it’s UPC format on their buyer form (without the leading ‘0’) and state that the format is UPC – if this is done, they have no problems using our barcodes.
Please contact us if you have any questions about this.