The four GTIN formats
- GTIN-8 - 8 digits, encoded as EAN-8. For very small retail packs.
- GTIN-12 - 12 digits, encoded as UPC-A. Used across the US and Canada.
- GTIN-13 - 13 digits, encoded as EAN-13. Used in the rest of the world.
- GTIN-14 - 14 digits, encoded as ITF-14 or GS1-128. For cartons and cases that contain retail units.
How GTINs relate to barcodes
A GTIN is the number; the barcode is its machine-readable image. EAN-13 and UPC-A are essentially the same number system at different lengths - a UPC-A converts to EAN-13 by adding a leading 0. The check digit at the end is always calculated from the other digits to catch scanning errors, and the generator adds it automatically.
Who issues GTINs
GTINs come from GS1, the global standards body. The first digits of your number are a GS1 company prefix that identifies the owner, and retailers' databases use it to look up your product. You get a GTIN by joining GS1 or buying from a GS1-authorized reseller - never invent one, because a fake or recycled number will fail at checkout or on Amazon.
Which GTIN should I use?
Match the GTIN to your market and package size. Products sold in US/Canada retail use GTIN-12 (UPC-A); elsewhere use GTIN-13 (EAN-13). Cartons and shipping cases use GTIN-14 (ITF-14 or GS1-128). Very small retail packs may qualify for GTIN-8 (EAN-8). Your retail customer or marketplace will state which one they require.
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