How to Read Universal Product Code (UPC) Barcodes

The UPC does all the classifications for the purchase of a product. So much so that every different size of the same product has a different UPC. The UPC is one of the most widely used barcode systems in the world. Seeing it on your everyday items probably would have gotten you to think, "hey, maybe I can read these barcodes myself?" Well you're right, you can read them yourself, without a barcode reader.

Barcode Description

• The 12-digit barcode that we use is the standard UPC-A. Each bar represents a particular number, depending on what's in the individual bar.
• Each bar is made of a particular arrangement of black and white bars. The number that a black bar depicts depends on its size.
• A white bar represents zero. The thinnest of the black bars represents 1; 2, 3 and 4 belonging to the successive black bars of increasing thickness, 4 being the thickest.
• Depending on these different bars interspersed with the white spaces, we get the barcode.

How to Read UPC Barcodes?

UPC Scanners
You get barcode scanners in the market that are meant to decode the UPC. For example, Symbol LS2208 bar code scanner is a general purpose scanner that includes the UPC-A (standard UPC). The MC3090 wireless scanner from Barcodes Inc., is another excellent barcode scanner for the UPC. If you don't want to actually go and buy a scanner but possess a smartphone, you're in luck. ScanLife barcode reader is a phone app that allows you to take a picture of the barcode through the phone camera, read the image and decode the barcode in the picture taken. The best part is, it's a free app!

Manually Reading the Barcode
A standard 12-bar UPC contains some common elements and then the ones that differentiate the product. Also note that reading the barcode with your eyes can be a strenuous process, so take it easy with the lines and use a magnifying glass if you have one.

• Look at the first and last sequence of lines on the barcode (a sequence of lines). There's two thin black lines separated by a white line.
• The black lines are the thinnest and therefore represent '1'. The white line is '0'. So you'll see that every barcode in the UPC contains a '101' at the start and the end. Also note that both the lines drop down lower than the other lines in the barcode, except the middle bars.
• The middle bars are an alternating sequence of 'white-black-white-black-white'. The black bars are thin, which makes the code '01010'.
• The rest of the bars each contain their own number codes. Each code represents a particular bit of information about the product.
• Now look at the numbers at the bottom of the barcode. Every number is associated to a panel of 4-line set. These numbers are again given a specific set of number codes (given below).
• The first 5-digit set contains information about the purchase of the item and the manufacturer information, like the number 3 would, let's say, means 'coupon'. The latter 5-digit set describes that particular item in detail, like the product size, version, etc.

UPC Standard Codes
Each of these numbers are given a set of number codes listed below:

0 = 3211,	1 = 2221,
2 = 2122,	3 = 1411,
4 = 1132,	5 = 1231,
6 = 1114,	7 = 1312,
8 = 1213,	9 = 3112.

Example: Now look at the first three digits of the barcode pictured (212). So the way to read the start of the barcode pictured would be - 101212222212122. When separated, each of the numbers on the barcode are represented by a four digit number, with 101 in the beginning, to tell the scanner that the barcode has started.

101	2122	2221	2122
Start	2	1	2

UPC Standard Prefixes
Here are the most common prefixes found on the UPC barcodes:

• 0, 1, 6, 7 and 8 are the most common; they are used on most everyday goods.
• 2 is used for things that vary in weight, like food.
• 3 means it's a medicine.

Reading the barcode can prove to be more than just a hobby. If you go someplace on your vacation, it would be good to know more about the item you're buying. Also, take care of your eyes when you try and read the barcode, especially if you already have eye problems. Apart from that, reading barcodes can become quite an interesting hobby!