How to Verify a UPC Number

The check digit of this UPC can be checked through calculation or a verification website.
••• barcode image by Fantasista from

A Universal Price Code is represented by a bar code that can be scanned at the point of purchase. A UPC consists of a six-or nine-digit company prefix, a five- or two-digit product number and a check digit. A specific algorithm determines the last number, which is used to confirm the accuracy of the first 11 digits. A UPC can be validated with a manual calculation that can be checked at a UPC-validation website.

    Write down a UPC. For example, 796030114977 is the UPC of a product. The last number is the check digit.

    Sum the digits in the odd positions, starting at the left. In this case you have 7 + 6 + 3 + 1 + 4 + 7 = 28.

    Multiply the answer in Step 2 by 3. The result is 84.

    Sum the numbers in the even positions, ignoring the last (12th) digit because that is the check digit that you are verifying: 9 + 0 + 0 + 1 + 9 = 19. Do not multiply this number by 3.

    Add the results from Steps 3 and 4: 84 + 19 = 103.

    Subtract the number in Step 5 from the next higher multiple of 10. In this example, the next multiple of 10 after 103 is 110, so subtract 103 from 110: 110 minus 103 = 7. This is the check digit in the UPC in Step 1, so it is verified.

    Enter the 12-digit UPC at a validation site like the Universal Product Code (UPC) Validation site and click on the "Validate" button. In this example, enter 796030114977, click on the button and see the message, “Universal Product Code (UPC) '796030114977' is valid."

Related Articles

How to Translate Bar Codes
How to Convert a Date to Hexadecimal
What Is the Difference Between ISBN 13 & ISBN 10?
How to Check Multiplication
How to Solve Improper Fraction Math Problems
How to Find the X Intercept of a Function
How to Read Roman Numerals
How to Find a Z Score
How to Calculate the Centerline of P Charts
How to Calculate Variance From a Ti84
Basic Mathematics Skills
How to Make a Relative Frequency Table
How to Find Z-Scores on a TI-84 Plus
How to Calculate the Day I Was Born
How to Divide Decimals for 5th Grade
How to Do Exponents Outside of the Parenthesis
How to Convert 4.0 System to 100 Point Grading System
How to Determine Your Cumulative GPA From College Transcripts