Attribute Guide
GTIN Attribute in Google Shopping: EAN, UPC & ISBN Requirements
Everything about the GTIN attribute for Google Merchant Center. Formats (EAN-13, UPC-A, ISBN), validation rules, when it's required, and how it affects…
Sony Alpha A7 III Mirrorless Camera Body
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Sony Alpha A7 III Mirrorless Camera
No reviews · No price comparison · Basic listing
GTIN unlocks review aggregation, price comparison, and richer results. Products with GTINs get higher auction priority and typically 20–30% better CPC efficiency.
What is the GTIN attribute?
GTIN (Global Trade Item Number) is a unique product identifier assigned by manufacturers through the GS1 system. In Google Merchant Center, the gtin attribute helps Google understand exactly what product you’re selling, match it with their global product catalog, and give you better auction placement.
Think of GTIN as the product’s “social security number” — it uniquely identifies a specific physical product variant across all retailers worldwide. When Google sees the same GTIN from multiple merchants, it can aggregate reviews, compare prices, and create rich product knowledge panels.
Technical specifications
| Feed name | gtin |
| Required | For all products with manufacturer-assigned GTINs |
| Accepted formats | EAN-13 (13 digits), UPC-A (12 digits), ISBN-13 (13 digits), JAN (8 or 13 digits), ITF-14 (14 digits) |
| Validation | Must include valid check digit. Prefixes 02/04 not accepted (internal use). |
GTIN formats explained
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EAN-13 (Europe) — 13 digits, most common globally. Example:
5901234123457 -
UPC-A (North America) — 12 digits. Example:
012345678905 -
ISBN-13 (Books) — 13 digits starting with 978 or 979. Example:
9780141036144 -
JAN (Japan) — 8 or 13 digits. A subset of EAN, used primarily in Japan.
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ITF-14 (Carton-level) — 14 digits. Used for outer packaging (case packs), not individual units.
Where GTIN is used
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Product matching — Google matches your GTIN against its global product catalog for accurate classification
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Auction priority — Products with valid GTINs get higher priority in Shopping auctions (confirmed by Google)
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Product reviews — GTIN enables automatic review aggregation from multiple sources across the web
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Price benchmarks — Google shows price comparisons across merchants for identified products
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Rich product knowledge panels — GTIN unlocks the full Shopping knowledge panel with specs, ratings, and price history
Rules
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Must be the correct GTIN for the specific product variant (color/size/configuration)
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Check digit must be valid (last digit calculated from preceding digits using Luhn algorithm)
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No prefixes 02 or 04 — these are reserved for store-internal/coupon use
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No dashes, spaces, or letters — digits only
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If product has no GTIN: set
identifier_existstono(Google also acceptsfalse— both work). If the product still has a brand or MPN, submit those alongside —identifier_exists: noonly signals the absence of a GTIN. -
Multi-packs need the GTIN of the multi-pack itself, not the individual item
Impact on performance
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20–30% higher CPC efficiency — Products with GTINs often pay less per click for the same position because Google has higher confidence in the product match
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Richer product listings — GTIN enables review stars, price comparisons, and product detail pages
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Fewer disapprovals — Missing GTIN on branded products triggers warnings that can escalate to suspension
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Better matching — Google shows your product for more relevant queries when it knows exactly what it is
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Price comparison eligibility — Only products with GTINs appear in Google’s price comparison features
Common mistakes
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Using internal SKU instead of GTIN (SKU is an internal identifier, not a global standard)
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Same GTIN for all size/color variants — each physical variant has its own GTIN
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Invalid check digit (a typo in any digit usually creates a bad check digit)
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Using GTIN prefix 02 or 04 (store-internal coupon codes)
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Leaving GTIN empty for branded products that have one — this is a policy violation
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Using EAN of the outer case pack (ITF-14) instead of the individual unit (EAN-13)
Pro tips
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Validate GTINs before uploading — Use a free online GTIN validator or GS1’s own GEPIR database. A single digit transposition is the most common error and is invisible to the human eye.
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For bundles: create a new GTIN — If you’re selling a bundle (e.g., camera + bag + memory card) that isn’t a manufacturer-packed set, you need to buy a GS1 registered GTIN for the bundle. Don’t reuse one of the component GTINs.
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Private label products can get GTINs — If you manufacture or white-label your own products, register for GTINs directly through GS1. The cost is a one-time fee plus annual subscription, and the ROI in better Shopping performance is typically very fast.
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Monitor for GTIN errors in the Diagnostics tab — GMC flags invalid GTINs under “Attribute Issues”. Fix these immediately — they have a disproportionate impact on feed quality score.
Frequently asked questions
What is GTIN and how is it different from EAN or UPC?
gtin field — Google accepts all formats.Is GTIN required for all products?
identifier_exists to false instead.What if my product doesn't have a GTIN?
identifier_exists to false. This tells Google the product legitimately has no GTIN (e.g., handmade goods, custom bundles, private-label). Don't leave the field empty for branded products that do have a GTIN — that causes warnings.