EAN-13 Barcode: From GTIN to a Retail-Ready Label
An EAN-13 barcode is the symbol a supermarket scanner reads at checkout. The number inside it is a GTIN-13, usually licensed through GS1, and the symbol is standardized down to the width of a module. The workflow is short, but the details — check digit, quiet zone, magnification — decide whether the code scans on a curved cereal box.
From GTIN to a scannable symbol
A GTIN-13 is twelve digits plus a check digit. The first digits identify the GS1 member organisation that issued the number (the prefix does not reliably identify where a product was made), the middle digits identify the item, and the last digit protects the rest. If you are selling under your own brand, obtain a prefix from GS1; reselling a borrowed number is a listing violation on every major marketplace.
- Enter the 12-digit base; the encoder appends the check digit and prints the human-readable number below the bars.
- One GTIN per variant: size, colour and pack count each need their own number.
- Keep the digits as text in your spreadsheet so leading zeros are not lost.
The check digit is not optional
The check digit is computed from the twelve data digits. Number the digits from the right, multiply alternately by 3 and 1, add the products, and subtract the last digit of the sum from 10. For 590123412345 the sum is 83, so the check digit is 7 and the full GTIN is 5901234123457. A scanner validates this before it looks at your product record; a wrong digit reads as “unknown item”, not as a typo.
Quiet zones and retail print size
The symbol needs blank space on both sides — at least eleven modules to the left and seven to the right for EAN-13 — plus clear space above and below. The nominal size is about 37.3 × 25.9 mm at 100% magnification; retail allows roughly 80–200%, and smaller than 80% is where cheap scanners start to struggle. Print bars dark and the background light, never the reverse, and avoid printing across a fold or a curved edge.
Before you upload to Etsy or Shopify
Marketplaces ask for a GTIN when one exists and for an exemption when it does not. Upload the number, not a picture of the barcode; the platform validates the check digit and may reject a reused or invalid GTIN. Test the printed label with a real scanner, not only a phone app — phone decoders are more forgiving than a checkout laser.
- Match the GTIN in the listing to the one printed on the label.
- Keep the label at 100% magnification on a flat, light surface for the first run.
- For cartons and pallets, move to ITF-14 or a GS1-128 label instead of shrinking an EAN-13.
Frequently asked questions
Do I need a GS1 licence to use an EAN-13 barcode?
For retail products, yes: the GTIN must be issued to your company. Marketplaces and retailers check the prefix, and a borrowed number can get a listing removed.
Can I encode letters in an EAN-13 barcode?
No. EAN-13 holds digits only. Use Code 128 or a QR code for text, and keep EAN-13 for the retail GTIN.
What is the smallest printable EAN-13?
Around 80% of nominal size, roughly 30 × 21 mm, and only on a flat surface with clean quiet zones. Below that, scanner tolerance drops quickly.
Does the barcode contain the price?
No. It carries the GTIN; the price lives in the retailer’s database. That is why a product can change price without a new label.