Enter your 11 or 12 digit UPC to get a UPC-A barcode. If you leave off the last digit, the check digit is calculated for you. Download PNG or SVG, or print.
A UPC-A has 12 digits. The first digits are the company prefix licensed from GS1, the next digits are the item number the company assigns, and the last digit is a check digit calculated from the other eleven. A scanner uses the check digit to catch misreads.
The check digit works like this: add the digits in the odd positions (1st, 3rd, … 11th) and multiply by 3, add the digits in the even positions, and the check digit is whatever brings the total up to the next multiple of 10. For 03600029145 that gives 2, so the full UPC is 036000291452.
At the standard 100% size (0.33 mm bar width) a UPC-A symbol is about 37.3 mm wide including its quiet zones, with bars about 23 mm tall. GS1 allows scaling between 80% and 200%. Avoid cutting the height down, which makes it harder to scan.
About the numbers: this tool draws a barcode for a number you already have. It does not issue product numbers. UPC and EAN numbers for products sold in stores come from GS1 (in the US, GS1 US), which licenses a company prefix to each brand. A number you make up yourself will scan, but it isn't registered to you, and retailers and marketplaces that check GS1 data may reject it.