Invalid value [gtin] in Merchant Center: how to fix GTIN errors in your feed

Updated 25 Sept 2026 · by Sergey Sachenok, Founder of Polyntor

Merchant Center showsInvalid value [gtin]

In short

A GTIN is the number under a product barcode. Google checks its length, its check digit and its range, and matches it against what it knows about the product.
Most errors come from the feed, not the product: a spreadsheet dropped a leading zero, a digit was mistyped, or one barcode was copied onto several items.
Only use the GTIN the brand owner assigned. Never invent one — a made-up number is worse than no number.
Products that truly have no GTIN (handmade, custom, vintage) should send brand and MPN, or set identifier_exists to no.
Fix the source of the data, not just the feed file, or the same error comes back with the next export.

Check your store for this now

A free scan of your store against Merchant Center policies. No card needed.

What this error means

GTIN (Global Trade Item Number) is the family of numbers printed under retail barcodes: UPC in North America, EAN in most other places, JAN in Japan, ISBN for books. You send it in the gtin attribute so Google knows exactly which product you sell.

Invalid value [gtin] means the value you sent cannot be a real GTIN at all: wrong number of digits, letters mixed in, or a last digit that does not add up. Depending on the case, the item is disapproved or its visibility is limited.

Related issues you may see: Invalid GTIN in unsupported format, Restricted GTIN and Unsupported GTIN (a range not meant for products), Incorrect GTIN (a valid number from another product), Incorrect product identifier (you said there is no identifier, Google thinks there is one) and Missing or incorrect GTIN, once called Limited performance due to missing identifiers.

The usual causes

Wrong length. Google accepts 8, 12, 13 or 14 digits. Spaces and hyphens are ignored; letters or an internal SKU are not a GTIN, and an old 10-digit ISBN must be converted to ISBN-13.
Bad check digit. One digit was mistyped or two were swapped. The last digit is calculated from the others, so a typo almost always breaks it.
Lost leading zero. Many UPCs start with 0. Open the feed in a spreadsheet, and the column is treated as a number: 012345678905 becomes 12345678905, eleven digits, and Google rejects it. A 13-digit EAN can also end up in scientific notation, like 4.00638E+12, and be exported like that.
Restricted or coupon range. Numbers starting with 2, 02 or 04 are what GS1 calls restricted circulation numbers, meant for use inside one company or region. Google treats numbers starting with 05, 98 or 99 as coupon ranges. Google does not accept either kind in the gtin attribute.
Made-up numbers. A number generated to fill the field, or copied from a similar product, can pass the check digit and still belong to another product. Google is explicit: do not guess, and do not borrow values from similar products.
The same GTIN on different products. Each size and colour of a product has its own GTIN. Reusing one barcode across variants or products can end up as Incorrect GTIN.

How the check digit works, in plain terms: take every digit except the last. Starting from the right, multiply them by 3, then 1, then 3, then 1, and so on. Add the results. The check digit is whatever you need to add to reach the next multiple of ten. For the GTIN-8 96385074, the first seven digits 9638507 give 7×3 + 0×1 + 5×3 + 8×1 + 3×3 + 6×1 + 9×3 = 86. The next multiple of ten is 90, so the check digit is 4. A zero in front does not change the sum, so putting a lost zero back makes the check digit correct again. To check a number quickly, use the GS1 check digit calculator.

Products without a GTIN, and where real ones come from

Not every product has a GTIN, and Google does not want you to create one. For handmade, custom, one-of-a-kind or vintage items you have two honest options, described in About unique product identifiers and the identifier_exists attribute:

Send brand and MPN. For your own products, Google suggests your store name as the brand and a part number you assign yourself as the MPN.
Set identifier_exists to no. Use it only when the product really has no GTIN, brand plus MPN, or other identifier. The accepted values are yes, true, no and false, in English.

Do not set identifier_exists to no just to make an error go away. If Google finds evidence that the product does have a GTIN, for example from similar offers that carry one, you get Incorrect product identifier and the item stays disapproved until you send the right number.

Real GTINs come from the brand owner, who licenses a company prefix from a local GS1 organisation and numbers each product from it. If you resell, the GTIN is on the packaging or you ask the manufacturer or distributor. If you own the brand, you get GTINs through GS1. You can look up who a barcode is registered to with Verified by GS1.

How to fix it and resubmit

Download the affected productsIn Merchant Center, open Products, go to the Needs attention tab and filter by the GTIN issue. Download the list.
Sort them by causeShort by one digit and fixed by a leading zero? A formatting problem. Right length but wrong check digit? A typo. Starts with 2, 02, 04, 05, 98 or 99? Not a product GTIN. Same number on several items? A copy-paste problem.
Fix the source, not only the fileCorrect the numbers where they live: your shop platform, ERP or spreadsheet. Format a spreadsheet gtin column as text so leading zeros survive the next export.
Replace numbers you cannot verifyTake the GTIN from the packaging or the supplier. If you cannot confirm it, leave gtin empty and send brand and MPN.
Give each variant its own GTINGroup variants with item_group_id, not by sharing one GTIN. A bundle you put together yourself carries the individual product's GTIN; a multipack made by the manufacturer uses the multipack's own GTIN.
Mark products that truly have noneFor handmade, custom or vintage items without any identifier, set identifier_exists to no, and make sure the gtin field is empty for those items.
Resubmit and wait for the updateUpload the corrected feed or fetch it again. Google says changes can take 24 to 72 hours to show on the Needs attention page.

Identifiers are one part of a bigger question Google asks about every listing: does it describe the product the buyer will actually get? If your feed and your product pages disagree in other ways too, see Mismatched price and Misrepresentation.

What Polyntor checks for this

GTIN length: 8, 12, 13 or 14 digits, with spaces and hyphens ignored
GTIN check digit, calculated the GS1 way
GTINs that lost a leading zero in a spreadsheet, with the value they should have
GTINs in restricted ranges (2, 02, 04) and coupon ranges (05, 98, 99)
The same GTIN used on more than one product in your feed
Products with no GTIN and no brand-plus-MPN pair, unless identifier_exists says there is none
identifier_exists values other than yes, true, no or false
identifier_exists set to no while the product still carries a GTIN or brand and MPN

Fixed it? Scan again before you request a review

A free scan of your store against Merchant Center policies. No card needed.

Questions

Can I buy cheap barcodes online instead of going to GS1?

GS1 calls itself the only official source of GTINs, and numbers it issues are registered to your company where anyone can look them up. A number from another source may be registered to a different company or none, and then it does not match your brand. Go to your local GS1 office.

I sell handmade products. Do I need GTINs?

No. Send your store name as the brand and your own part number as the MPN, or set identifier_exists to no. Do not invent a GTIN to fill the field.

My GTIN is correct on the packaging but Merchant Center says it is invalid. Why?

Usually something happened between the packaging and the feed. The most common culprit is a spreadsheet that removed the leading zero or turned the number into scientific notation. Open the raw feed in a text editor and count the digits.

Can two of my products share a GTIN?

Only if they really are the same product, and then they should not be two listings. Each size, colour or pack size has its own GTIN, and Google asks you not to submit several products with the same GTIN and the same variant details for one country and language.

Should I just set identifier_exists to no for everything?

No. It only suits products that genuinely have no identifier. When Google has evidence that a product does have a GTIN, a no gets flagged as Incorrect product identifier and the product can stay disapproved.