GTIN-8
7 body digits; 8 including the check digit.
Open this formatGS1 Mod-10 utility
GTIN-12 / UPC-A check digit calculator
Enter 11 body digits to generate a 12-digit GTIN-12 / UPC-A, or switch to Validate and enter all 12 digits. Leading zeros are preserved.
GTIN-12 / UPC-A worked example
How to calculate a GTIN-12 / UPC-A check digit
- A GTIN-12 has 11 body digits and one final check digit. Preserve every leading zero.
- For body 61414121022, the odd-position digits total 18, then 18 × 3 = 54. The even-position digits total 6, giving a weighted sum of 60.
- 60 is already a multiple of 10, so the check digit is 0 and the complete GTIN-12 is 614141210220.
GTIN-12 is the only GTIN used in a UPC-A barcode. This arithmetic does not create a barcode image, issue or look up a GTIN, convert an ASIN, prove authenticity, or confirm a product assignment.
Exact GTIN-12 / UPC-A calculationBody: 61414121022
3 × 18 + 6 = 60; (10 − 60 mod 10) mod 10 = 0.
Check digit: 0 · Complete value: 614141210220
Calculator
GS1 Mod-10 check digit
Supported formats
Exact lengths, one shared rule
GTIN, GLN and SSCC use the same GS1 Mod-10 arithmetic but have different required lengths. CheckDigit validates the length before calculating.
GTIN-12 / UPC-A
11 body digits; 12 including the check digit.
Open this formatGTIN-13 / EAN-13
12 body digits; 13 including the check digit.
Open this formatGTIN-14
13 body digits; 14 including the check digit.
Open this formatGLN-13
12 body digits; 13 including the check digit.
Open this formatSSCC-18
17 body digits; 18 including the check digit.
Open this format