Free UPC generator and barcode maker

A UPC-A holds a 12-digit number called a GTIN-12. The first digits are the company prefix that GS1 licensed to the brand owner, the next digits are the item number the brand chose, and the last digit is a check digit worked out from the other 11.

The bars encode each digit as 7 narrow units (modules) of two bars and two spaces. Three longer guard bars mark the start, middle and end, and white margins called quiet zones sit on both sides: 9 modules each side for UPC-A, 11 on the left and 7 on the right for EAN-13. A scanner reads the check digit last and rejects the scan if it doesn’t add up, which is why a typo in one digit almost never scans as a different product.

To work it out by hand, multiply the digits by 3 and 1 in turn, starting with 3 on the digit just left of the check digit, add the results, and take the amount needed to reach the next multiple of 10. For the UPC on the left:

0×3 + 3×1 + 6×3 + 0×1 + 0×3 + 0×1 + 2×3 + 9×1 + 1×3 + 4×1 + 5×3
= 58
Check digit = (10 − 58 mod 10) mod 10 = 2
Full number: 036000291452

Any 12 digits with the right check digit make a barcode that scans. Whether the number is accepted as your product depends on who owns it. GS1 is the only organization that issues company prefixes, and marketplaces check numbers against its records: Amazon and Walmart both say they check product IDs against the GS1 database and recommend getting them straight from GS1.

In the US you license numbers from GS1 US. One GTIN costs $30 with no yearly fee. A company prefix for 10 products costs $250, then $50 a year (GS1 US prices, checked October 2026). With a prefix, you choose the item numbers and this tool works out the check digit and draws the barcode.

Numbers sold cheaply by resellers often come from old prefixes licensed to another company, so the brand on record won’t match yours. Google Merchant Center flags a GTIN that doesn’t belong to the brand you send, and Amazon can remove listings whose numbers don’t match GS1.

For barcodes that never leave your business, use an in-store number: GS1 keeps UPCs that start with 4 for use inside one company. Open “Make an in-store number” above to make one from your own item number.

The GS1 numbers below are built into the tool, so a download at 100% already has the right bar height and margins. They matter when you place the barcode on artwork or resize it.

• Size: GS1 allows 80% to 200% for UPC and EAN. At 100% a UPC-A or EAN-13 is 37.29 mm (1.47 in) wide, margins included. Resize the whole barcode, never just its width.
• Height: GS1 says not to cut bars short (truncate) unless the pack is too small. Short bars can fail barcode verification and are harder to scan at an angle.
• Margins: keep the white quiet zones clear of text, edges and folds.
• Colors: dark bars on a light background. Black, dark blue and dark green work; red, orange, yellow and brown bars look blank to the red light in most scanners. The tool warns you when a color won’t scan.
• Cartons: print ITF-14 at 150% or more (bars at least 0.495 mm), with the bearer bars the tool adds.
• Placement: GS1 recommends the lower right of the back of the pack, at least 8 mm from any edge.
• Files: use the SVG for print artwork, so the bars stay sharp at any size; use the 300 dpi PNG for labels and documents.

This tool makes and checks barcodes; it doesn’t look up products. To see which company a UPC or EAN is licensed to, search it in the GS1 company database. If the company shown isn’t yours, the number won’t pass marketplace checks for your brand, even if its check digit is right.

To check a batch of numbers before you upload a product file, paste them into “Check a list of numbers” above. It checks the length and the check digit of up to 200 numbers at once.