What number you paste on Mercado Libre
The 13-digit one. One per variation. You download it in the Excel as soon as you pay.
What you paste on Mercado Libre
On the listing, the field is universal code, EAN, or GTIN. Paste the 13 digits of the EAN-13, one per variation. The 12-digit UPC is the same number without the leading 0.
When you need another number
Another color, size, flavor, scent, or fill (250 ml vs 500 ml) sold separately: another code. The same shirt in S, M, and L is three. A shirt in 3 colors and 4 sizes is 12. Price or a new photo keep the same code.
UPC and EAN: the same code, two formats
Each code in the pack ships as UPC-12 and EAN-13. The EAN is the UPC with a leading 0. On Mercado Libre you paste the 13-digit one. On Amazon the field is usually GTIN.
After you buy
Open the Excel. One code per SKU. Note the description. Paste the EAN-13 on Mercado Libre and the GTIN on Amazon. Send the SVG to the printer. Save the certificate.
What you paste on Amazon
The field is GTIN: UPC or EAN of the same code, one per variation. Amazon assigns the FNSKU when you send stock to FBA. To list, paste the GTIN.
Print a scanner can read
Dark bars on a light background. Do not crop the sides. Do not shrink below 80% of the size we send. Test a real scanner before a large run.
The last digit
It is a check digit: if someone typed it wrong, the scanner or listing catches it. On the certificate it is red. The check-digit tool does the math.
If you publish a magazine
If it hits the register, one UPC. One title, one code. Pay and download the artwork now.