ID Key Format 
Digit Positions 
GTIN8 










N_{1} 
N_{2} 
N_{3} 
N_{4} 
N_{5} 
N_{6} 
N_{7} 
N_{8} 
GTIN12 






N_{1} 
N_{2} 
N_{3} 
N_{4} 
N_{5} 
N_{6} 
N_{7} 
N_{8} 
N_{9} 
N_{10} 
N_{11} 
N_{12} 
GTIN13 





N_{1} 
N_{2} 
N_{3} 
N_{4} 
N_{5} 
N_{6} 
N_{7} 
N_{8} 
N_{9} 
N_{10} 
N_{11} 
N_{12} 
N_{13} 
GTIN14 




N_{1} 
N_{2} 
N_{3} 
N_{4} 
N_{5} 
N_{6} 
N_{7} 
N_{8} 
N_{9} 
N_{10} 
N_{11} 
N_{12} 
N_{13} 
N_{14} 
SSCC 
N_{1} 
N_{2} 
N_{3} 
N_{4} 
N_{5} 
N_{6} 
N_{7} 
N_{8} 
N_{9} 
N_{10} 
N_{11} 
N_{12} 
N_{13} 
N_{14} 
N_{15} 
N_{16} 
N_{17} 
N_{18} 
Step 1: Multiply value of each position by 

x3 
x1 
x3 
x1 
x3 
x1 
x3 
x1 
x3 
x1 
x3 
x1 
x3 
x1 
x3 
x1 
x3 

Step 2: Add results together to create sum 
Step 3: Subtract the sum from nearest equal or higher multiple of ten = Check Digit 
The following table gives an example to illustrate how a GTIN13 Check Digit is calculated:
Positions 
N_{1} 
N_{2} 
N_{3} 
N_{4} 
N_{5} 
N_{6} 
N_{7} 
N_{8} 
N_{9} 
N_{10} 
N_{11} 
N_{12} 
N_{13} 
Number without Check Digit 
6 
2 
9 
1 
0 
4 
1 
5 
0 
0 
2 
1 
 
Step 1: Multiply 
x 
x 
x 
x 
x 
x 
x 
x 
x 
x 
x 
x 
 
by 
1 
3 
1 
3 
1 
3 
1 
3 
1 
3 
1 
3 
 
Step 2: Add results 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
 
to create sum 
6 
6 
9 
3 
0 
12 
1 
15 
0 
0 
2 
3 
=57 
Step 3: Subtract the sum from nearest equal or higher multiple of ten = 60 57 = 3 (Check Digit) 
Number with Check Digit 
6 
2 
9 
1 
0 
4 
1 
5 
0 
0 
2 
1 
3 