What Is a GTIN? GTIN-8, GTIN-12, GTIN-13 and GTIN-14 Explained
What is a GTIN, and how do GTIN-8, GTIN-12, GTIN-13 and GTIN-14 differ?
Short answer
A GTIN (Global Trade Item Number) is the GS1 number that identifies a product or a package of products; the barcode is only the way a scanner reads it. GTINs come in 8, 12, 13 and 14 digits, and the shorter ones can be padded with leading zeros to 14 digits without becoming a different number.
On this page
You have probably met the term on a marketplace listing form, a retailer's item setup sheet or a supplier's spreadsheet, sitting next to fields labeled UPC and EAN. It looks like one more competing code. It isn't: UPC and EAN numbers are GTINs, just written at different lengths.
This guide explains what a GTIN identifies, the four lengths it comes in, what the digits mean, and why leading zeros cause so much confusion in spreadsheets and listing tools.
A GTIN is a number; the barcode carries it
GS1, the organization that runs the system, describes the GTIN as the number a company uses to identify all of its trade items. A trade item is any product or service that is priced, ordered or invoiced at some point in the supply chain (GS1).
The barcode is a separate thing. GS1 US puts it plainly: the GTIN identifies the product, and the UPC is the barcode that lets a scanner read that GTIN (GS1 US FAQ). The same GTIN can appear in more than one barcode type, and the number stays the same.
In practice, when a form asks for a product's "UPC," it wants the 12 digits printed under the bars, not an image of the barcode.
The four GTIN lengths
GS1 defines four GTIN formats: GTIN-8, GTIN-12, GTIN-13 and GTIN-14 (GS1 General Specifications). Each one has a usual barcode and a usual job.
| Format | Digits | Usual barcode | Typical use |
|---|---|---|---|
| GTIN-12 | 12 | UPC-A, or UPC-E for small packs | Retail products, mainly in North America |
| GTIN-13 | 13 | EAN-13 | Retail products, mainly outside North America |
| GTIN-8 | 8 | EAN-8 | Very small retail packages, mainly outside North America |
| GTIN-14 | 14 | ITF-14 or GS1-128 | Cases and other groupings that are not sold at checkout |
GS1 US describes GTIN-12 as the format used mostly in North America and GTIN-13 as the one used mostly elsewhere. Both work at retail checkouts (What is a GTIN?). How UPC-A and EAN-13 relate, and when U.S. stores accept EAN-13, is covered in UPC vs. EAN.
GTIN-8 exists only for packages too small for a full-size barcode. The General Specifications allow it when the package's total printable area is under 80 cm², the largest label is under 40 cm², or a cylindrical product is less than 30 mm across. GTIN-8s are assigned one at a time by GS1 member organizations on request, and GS1 US notes they are used mostly outside North America. A small U.S. package can instead carry its GTIN-12 as a UPC-E barcode, which shortens the symbol by suppressing certain zeros.
GTIN-14 identifies a grouping, such as a case of 12 identical units. GS1 US notes that a GTIN-14 never starts with zero. It is not meant for scanning at the retail checkout. Shipping-carton barcodes are covered in ITF-14 shipping carton barcodes.
What the digits mean
Take the GTIN-12 614141123452, an example number GS1 uses in its own documentation. It has three parts:
- 614141 is the U.P.C. Company Prefix, the part GS1 assigns to the brand owner. In a UPC, GS1 US says this part is 6 to 10 digits long (What is a UPC Code?).
- 12345 is the item reference, which the brand owner assigns to a specific product. The longer the prefix, the fewer digits are left here, which is why prefixes come in different capacities.
- 2 is the check digit, calculated from the other 11 digits.
There is a hidden zero in that number, too. A U.P.C. Company Prefix is a GS1 Company Prefix with its leading zero removed. GS1's own example is the 12-digit GTIN 614141234561, whose GS1 Prefix is 061, not 614 (GS1 Company Prefix). That implied zero is why every GTIN-12 can also be written as a 13-digit number that starts with 0.
The check digit uses the same mod-10 method for every GTIN length: weights of 3 and 1, a sum, and the difference to the next multiple of ten. GS1 describes it as the digit that protects the integrity of the key (GS1 check digit calculator). You can validate any GTIN-8, GTIN-12, GTIN-13 or GTIN-14 with the check digit calculator.
Leading zeros: one GTIN, several ways to write it
Some barcodes, such as GS1-128, and many databases work with a fixed 14-digit field. The General Specifications handle this by padding shorter GTINs on the left with zeros. Those zeros are filler, and adding or removing them does not change the GTIN.
So these three strings are the same product:
| Written as | Value |
|---|---|
| GTIN-12 | 614141123452 |
| 13-digit form | 0614141123452 |
| 14-digit form | 00614141123452 |
A GTIN-14 is different. It is a new number for a grouping, not padding. To build one for a case, you put an indicator digit from 1 to 8 in front of the contained item's GTIN (without its check digit), then calculate a fresh check digit. The General Specifications use this exact example: indicator 1 plus 061414112345 gives 10614141123459. Indicator 9 is reserved for variable-measure items.
The trap runs the other way with GTIN-12s that genuinely start with zero. The General Specifications note that a GTIN-12 can begin with one, two or three zeros that belong to the company prefix, and those zeros must be kept. A spreadsheet column formatted as a number silently drops them, leaving a value too short for any system that expects 12 digits. Format GTIN columns as text before you paste or import.
Where GTINs come from
GTINs are licensed through GS1 member organizations. In the United States that is GS1 US, which offers single GTINs and GS1 Company Prefixes; the step-by-step process is in how to get UPC barcodes.
Some number ranges look like GTINs but are not meant for open trade. The General Specifications reserve 12-digit numbers starting with 2 for restricted use within a geographic region, and those starting with 4 for use within a single company. These Restricted Circulation Numbers are useful for in-store or internal labels but should never stand in for a product's GTIN.
Finally, GS1 US says each product variation gets its own GTIN, with size, color, style and package count as examples. One GTIN for a whole product family defeats the purpose of the number.
Bottom line
A GTIN is the product's identity number, and the barcode is just how machines read it. GTIN-12 and GTIN-13 identify retail units, GTIN-8 is a rare small-package option, and GTIN-14 identifies cases and other groupings. Zeros added in front to pad a GTIN to 13 or 14 digits don't change the number, but zeros that are part of a GTIN-12's company prefix must never be dropped.