About unique product identifiers

Unique product identifiers define the product that you're selling in the global marketplace. They uniquely distinguish products that you are selling and help match search queries with your offers. Unique product identifiers are assigned to each product by the manufacturer, so if you sell the same product as another retailer, the UPIs will be identical.

Common unique product identifiers include Global Trade Item Numbers (GTINs), Manufacturer Part Numbers (MPNs) and brand names. Not all products have unique product identifiers. However, if your product does have one, especially a GTIN, providing it can help make your ads richer and easier for users to find. If your product doesn't have a UPI, you'll tell us so in your product data.

This article explains the unique product identifiers that you may have to provide, how to troubleshoot issues with your identifiers and what to do if you don't have them.

Types of unique product identifiers

Attribute Name Description
gtin [gtin] UPC
  • Used primarily in North America
  • Universal Product Code (UPC), also called GTIN-12 and UPC-A
  • 12 numerical digits
  • A unique numerical identifier for commercial products that's usually associated with a barcode printed on retail merchandise.
gtin [gtin] EAN
  • Used primarily outside of North America
  • European Article Number (EAN), also called GTIN-13
  • Typically 13 numerical digits (can occasionally be either eight or 14 numerical digits)
  • A unique numerical identifier for commercial products that's usually associated with a barcode printed on retail merchandise.
gtin [gtin] JAN
  • Used only in Japan
  • Japanese Article Number (JAN), also called GTIN-13
  • 8 or 13 numerical digits
  • A unique numerical identifier for commercial products that's usually associated with a barcode printed on retail merchandise.
gtin [gtin] ISBN
  • Used globally
  • International Standard Book Number (ISBN)
  • ISBN-10: 10 numerical digits (last digit may be 'X' which represents the number '10').
  • Note that this format was deprecated in 2007, and not all books can be represented using ISBN-10.
  • ISBN-13 (recommended): 13 numerical digits and typically starts with either 978 or 979
  • A unique numerical identifier for commercial books published since 1970 that can be found on the back of the book, along with the barcode.
brand [brand] Brand
  • Used globally
  • The brand of the product
  • Should be clearly visible on the front of the product packaging or label
mpn [mpn] MPN
  • Used globally
  • Manufacturer Part Number (MPN)
  • Alphanumerical digits (various lengths)
  • The number that uniquely identifies the product to its manufacturer

How to include unique product identifiers in your product data

Depending on the type of product that you submit, you'll submit different identifiers. For all your items, we recommend submitting all three attributes (gtin [gtin], brand [brand] and mpn [mpn]) to help boost ad performance and help users find your products.

id [id] title [title] identifier_exists [identifier_exists] gtin [gtin] mpn [mpn] brand [brand]
9876-S-GRN Google T-shirt – Green – Small - 9504000059422 00638HAY Google
9876-S-YELLOW Google T-shirt – Yellow – Small - 9504000059446 00638ANG Google
9877-M-Black Black T-shirt – Customised with your design no - - -


Use the following set of rules to provide the correct identifiers for each of your products.

Product identifier requirements
Regardless of category

The gtin [gtin] attribute is required if the product is widely manufactured and has a GTIN.

  Clothing Media Other categories

Required product identifiers based on category

Requires a value for the brand [brand] attribute Requires a value for the gtin [gtin] attribute (for example, ISBN)

Requires a value for the brand [brand] attribute (if there is no brand, provide the manufacturer/supplier name)

If there is no GTIN, provide the mpn [mpn] attribute.

Otherwise If product identifier requirements are not met, then your item's performance may be limited.

Products with GTINs

For all widely manufactured products (which are submitted with the condition attribute) that have a GTIN assigned, submit the following attributes:

  • gtin [gtin]
  • brand [brand]
  • mpn [mpn]

Products without a GTIN

Some products don't have a GTIN assigned, and so you don't need to submit one. However, if the product does have a GTIN assigned and you don't submit it, the product's performance may be limited.

For these products, submit the following attributes:

  • brand [brand]
  • mpn [mpn]

Examples of products that may not have an assigned GTIN include:

  • Store-brand products
  • Replacement parts
  • Original Equipment Manufacturer (OEM) parts or replacements for OEM parts
  • Custom-made products (custom t-shirts, art and handmade goods)
  • Books released before ISBN was approved as an ISO standard in 1970
  • Vintage or antique products
  • Pre-order products (using the condition [condition] attribute)

To help identify your products without a GTIN, you can use the mpn [mpn] and brand [brand] attributes. An MPN, or Manufacturer Part Number, is a UPI for specific parts assigned by the manufacturer. The brand [brand] attribute allows you to use the brand of your product as a UPI.

Note: The mpn [mpn] attribute is optional, but including it may improve your ad's performance. Bear in mind that your products may be disapproved or their performance may be limited if you submit products without a UPI when one is available.

Products without a brand

If the product has a clearly associated brand or manufacturer, submit the brand [brand] attribute.

However, you don't need to submit the brand [brand] attribute if the product doesn't have a clearly associated brand (for example, movies, books and music) or is a custom-made product (for example, custom T-shirts, art and handmade goods).

Tips for specific products

Books and media 

  • Use the ISBN-13 of a book as the value for the gtin attribute.
  • For a product that has a UPC and an ISBN-13, submit the gtin attribute twice, once for each value.
  • For a product with only an SBN (9 digits, used in Great Britain until 1974), convert it to an ISBN-10 by adding a 0 in front. For example, to convert 123456789, submit 0123456789.


A bundle is a main product that you've grouped with other accessory products, sold together as one package for a single price.

  • If the manufacturer created the bundle: use the GTIN, MPN and brand of the bundle, not the individual products.
  • If you created the bundle: use the GTIN, MPN and brand of the main product. For example, if you bundle a camera with a lens and carrying bag, submit the brand of the camera, which is the main product. Learn more about submitting bundles.

Compatible third-party products

Customised products

If you offer customisation, engraving or other personalisation of a product, explain that the product is customised in the title and description attributes.

  • Submit the gtin attribute with the value assigned by the manufacturer if you offer customisation, engraving or other personalisation of a product.
  • Use the is_bundle attribute to let us know that the product includes customisation.

Magazine subscriptions

An International Standard Serial Number (ISSN) can be converted into a GTIN. Learn more about converting values from the ISSN Center's website



A multipack is a group of several identical products for sale as one product. This group can be created by you or by the manufacturer, and you'll need to submit the brand differently depending on who created the group.

  • If the manufacturer created the multipack: use the gtin, mpn and brand of the multipack, not the individual products.
  • If you created the multipack: use the gtin, mpn and brand of the individual products. Learn more about the multipack attribute.

Printed music

An International Standard Music Number (ISMN) can be converted into a GTIN. Learn more about ISMN

Printer cartridges

Submit the correct GTIN value for your printer cartridge. Learn more about requirements for printer cartridges

Products available in variant colours or sizes

If your product comes in multiple colours or sizes, you have different unique product identifiers for each of these variants. For example, if you sell a shirt that comes in blue, red and green, you'll need to submit the colour attribute and a unique gtin for each variant. Learn more about the size [size] and color [colour] attributes.

Products with several GTINs

Make sure that you submit the correct GTIN for each product:

  • For variants (products that come in multiple colours, sizes, etc.), submit 1 GTIN for each product.
  • For products with more than 1 valid UPI (for example, products with a global GTIN and a GTIN specific to the distributor), submit additional UPI attributes with each value.

Own-brand and white-label products

Don't submit a GTIN for products without a GTIN. If you're the only seller of a product or if your product is a shop brand, it may not have a GTIN, and if so you don't need to submit one. Instead, submit the brand [brand] and mpn [mpn] attributes for these products.

White-label products are products that are produced by one company, but relabelled by the company selling them to make it look like they produced them. For example, Company A makes a connected TV device. Company B buys it to resell and rebrands it with their logo and name.

Used and vintage products

Used or vintage products may have a gtin, and you should provide it if possible.

  • Submit the gtin attribute with the value assigned by the manufacturer.
  • Submit the used [used] value for the condition [condition] attribute.  

Troubleshoot GTIN issues

Find unique product identifiers for your products

When you're working with unique product identifiers, don't invent or approximate the values. Each product has a prescribed value assigned by the manufacturer and any other value will cause your product to be disapproved. The most accurate source of GTINs is always from the product packaging or the product's manufacturer.

Ways to find unique product identifiers:

  • Check the packaging. Refer to the GTIN on your product's packaging. Learn how to find the GTIN
  • Ask the manufacturer. Contact your product's manufacturer or distributor to ask for it.
  • Search for the product on Google Shopping. For some countries, if you search for the product, the Shopping ad will have a link to compare prices. Click this link, and then look for the GTIN under the Details section.
  • Check ISBNdb.com or Google Books. You can find ISBN information on either of these sites.
Make sure that your GTIN is correct

Quickly check if your GTIN is correct using the following tips:

  • Use the right number of digits. Each GTIN should have a specific number of digits, so count the number of digits for each GTIN (for example, ISBN-13 should have 13 digits).
  • Use numbers only. If your GTIN has letters or symbols, it's not correct.
  • Look for the check digit (or letter for ISBN-10). The check digit is a digit within the GTIN that can be used as a mathematical check to make sure that the product identifier is accurate. Use the GS1 check digit calculator
  • Look for numbers in the restricted range. Don't include GTINs in the restricted ranges (prefixes 2, 02, 04) or the coupon range (99, 981–984).
  • Use the right levels. For GTIN-14 codes, only use packaging levels (1–8) if you are selling packages containing multiple items, do not use the bulk level indicator (9).
  • Make sure that you don't submit a reserved code GTIN. Some GTIN prefixes are not yet assigned because they are reserved for future use. If you use a GTIN with such a prefix, we will let you know on the Diagnostics tab in Merchant Center so that you can adjust it.

For more detailed information about GTIN validation, download the GS1 GTIN validation guide.

Related links

Was this helpful?
How can we improve it?

Need more help?

Sign in for additional support options to quickly solve your issue