Searching For Barcode Information?
- How Do I Use This Site?
- What are EAN-13 bar codes?
- What are UPC bar codes?
- How is the check digit calculated?
- What is the difference between UPC-A and UPC-E?
- How are the EAN-13/UPC-A/UPC-E barcodes created?
- What about the digits under the barcode?
- UPC Format For Audio/Video Products
- Learn about many different types of barcodes
- Find more information in our BLOG
- Return To The Main Page
How Do I Use This Site?
Enter the 8 or 12 digits found on the barcode of almost any product in the search box at the top of any screen and click the the lookup button. If the bar code doesn't match this format, it may not be an actual UPC code and would not appear in our database. It could be one of many formats. See the images below for examples of both the 8 and 12 digit UPC barcodes.
If you have a barcode scanner, you can simply scan the barcode while the input box is active. Most scanners will convert the scan into keyboard strokes. Often scanners will send a new line character after the barcode which would be the same as clicking the lookup button.
Our program will search through our database and try to locate the product information for you. In some cases we have information relating to the manufacturer and we may even have links to a product or manufacturer web page.
EAN-13 (13 digits)
UPC-A (12 digits)
UPC-E (8 digits)
What are EAN-13 bar codes?
EAN-13 is a superset of UPC. This means that EAN-13 includes all UPC codes and the UPC standard but it includes additional data (one digit) to give product codes for other countries. UPC is intended for USA and Canada. UPC codes are 12 digits. To turn an UPC code into an EAN-13 code all that is needed is to add a zero to the front of the number. The barcode doesn't change. Look at the images above, you will notice that the number on the EAN-13 looks different than the UPC-A number but the actual bars are exactly the same. Only when the first digit of an EAN-13 code is not a zero is the barcode change. We will give you more information on this below.
What are UPC bar codes?
UPC stands for Universal Product Code. These bar codes can be found on just about any product in your kitchen cabinets. They are used to for many things but mainly to help merchants keep track of and identify the products they sell.
A manufacturer first applys to the UCC (Uniform Code Council) for a six-digit manufacturer identification number. An annual fee is paid for the membership in the UCC who not only issues the manufacturer ID numbers, but provides guidelines on how to use it.
You can see the there are two main parts to a UPC symbol. There is the numbers which are human readable and the barcode which is machine readable. The barcode simply lets the machine know what the numbers are. It is much easier for a machine to read the lines and decode them than it would be to teach the machine to read the text numbers.
The numbers are the real UPC code. The digits are divided into 4 parts as follows...
- The first digit is the Number System Character. This digit use to tell us what type of UPC we are looking at. This seems to be less true any more especially. This would only apply to UPC-A codes anyway. EAN13 codes are a different story all together.
0 Standard UPC number (UPC-E always start with zero) 1 Reserved for future use 2 Random-weight items (fruits, vegetables, meats, etc.) 3 Pharmaceuticals 4 In-store marking for retailers (stores make up their own codes) 5 Coupons 6 Standard UPC number 7 Standard UPC number 8 Reserved for future use 9 Reserved for future use
With the expansion of the UPC system, digits 1, 8 and 9 are now being used. Unfortunatly, I have not yet found good information on these yet. I will keep looking
- The manufacturer identification number. This is the made up of
the Number System Character and the next 5 digits to uniquely
identify the manufacturer of the product. If you need more information
about connecting the UPC code to the Company information, please take
a look at the Connecting Companies page.
- The product code are the next set of 5 digits. These are assigned
by the manufacturer. Each company can make its own rules about
how it uses these numbers as long as it doesn't use the same
code for more than one product, everything will work fine.
- The last digit is known as the check digit. It is used to verify that the number scans properly. Most scanners will scann in all digits then independantly calculate the check digit and make sure it matches what it scanned in. When the scanned check digit matches the calculated check digit the machine considers it a valid scan and continues. If the two check digits don't match, the scanner will reject the entire number and the barcode needs to be scanned again. Below there is more information on calculating the check digit.
EAN Check Digit
How is the check digit calculated?
When you calculate the check digit you always use the first 11 digits of the 12 digit UPC-A formatted code or the first 12 digits of the EAN-13 formatted code. The UPC-E code must first be in the 12 digit UPC-A format before the check digit can be calculated. So if you are trying to calculate the check digit of a UPC-E code, you must restore the code to the UPC-A format first. Many scanners do this automatically for you if you want. They always do this in order to check the check digit but they don't automatically send the 12 digit version to the computer unless programmed to do so.
For our example, we will use the code shown in the picture above and walk through the process one step at a time. The full 12 digit UPC-A code for the image above is 064200115896. Remember, the last digit is the check digit so when we calculate our own check digit we only use the first 11 digits. When done we will compare it to the scanned digit 6 and make sure they match.
- Start with the first 12 digits of an EAN-13 code. If you are calculating the check digit for UPC-A, then put an extra zero as the first digit to get 12 digits not counting the check digit of course.
(leading zero added) Take the first 12 digits 0000642001151
- If you are trying to verify the check digit on an existing code, simply check the digit you calculate against the last digit of the full code. They should match or the entire number is considiered invalid. In this case, the full code would be 0000642001151 making the last digit 1.
- Add up the EVEN digits (every other digit) to get a total.
0 + 0 + 4 + 0 + 1 + 5 = 10
- Multiply this number by 3
10 x 3 = 30
- Add all the ODD digits together.
0 + 0 + 6 + 2 + 0 + 1 = 9
Now add the results of the last two steps together.
30 + 9 = 39
- Finally, the check digit is the number required to bring the results of the previous step to the next higher multiple of 10.
39 + 1 = 40
- Because 40 is the next number that is a multiple of 10 and you need to add 1 to 39 to get to 40, our check digit is 1 in this case.
- For your programmers out there, I would suggest using this formula which makes use of the MODULO function. (depending on the language it is MOD or % or \)
((10 - (39 mod 10)) mod 10) = 1
This calculator is available as a download in
spreadsheet or text format.
If you want to see this as a Visual Basic function, click here for a good example.