GTIN Check Digit Calculator
Calculate the GS1 check digit for any GTIN, EAN or UPC, or enter the full number to check that its last digit is correct.
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Learn MoreHow the GTIN Check Digit Works
Every GTIN, EAN, and UPC ends in a single check digit that lets a scanner detect mis-reads and typos. It is calculated from the other digits using the GS1 modulo-10 algorithm: working from the right, each digit is multiplied alternately by 3 and 1, the products are summed, and the check digit is whatever brings that sum up to the next multiple of 10.
Worked Example
For the 12 data digits 890123456789: multiply alternately by 3 and 1 from the right, add the results, then subtract that sum from the next multiple of 10. The remainder (mod 10) is the check digit, giving a complete EAN-13.
Generate vs. Validate
This calculator adds the correct final digit to a number you're creating. To check an existing number, enter all of its digits and the calculator confirms whether the last digit is right. A mismatched check digit can indicate a typo, a printing fault, or a counterfeit label.
Note: A valid check digit confirms the number is well-formed, not that the GTIN is registered to a company. Official GTINs are allocated by GS1. Runs entirely in your browser.
About the GTIN check digit calculator
Calculate or check the GS1 check digit for GTIN-8, GTIN-12 (UPC), GTIN-13 (EAN) and GTIN-14 numbers.
How to use it
- Enter the number without its last digit to calculate the check digit, or the full number to check it.
- The tool applies the GS1 modulo-10 method.
- Use the full number on your label or in your product master data.
Questions and answers
What is a check digit?
The last digit of a GTIN, calculated from the others. Scanners use it to catch typing and print errors.
Does a correct check digit mean the GTIN is registered?
No. It only means the number is well formed. Registration is confirmed with GS1, for example through GS1 India.
Which lengths are supported?
GTIN-8, GTIN-12, GTIN-13 and GTIN-14.