mpn is the manufacturer’s own code for the product, up to 70 characters, required together with brand for products that have no manufacturer-assigned GTIN and optional for custom-made goods. It is not your SKU: Google’s page says to provide an MPN only if you are sure it is correct, and never to guess or make one up.
| Attribute | mpn |
|---|---|
| Requirement | Required for all products without a manufacturer-assigned GTIN; optional for custom-made products. |
| Format |
|
Google’s rules for mpn
- Only the manufacturer’s part number, as printed in their catalogue or on the box.
- Do not guess or make up a value; when in doubt, leave it out.
- Not needed when a valid GTIN is present.
Common mistakes, and the error each one becomes
- The shop’s SKU mapped into mpn by an export template. → Incorrect product identifier [mpn]
- The GTIN repeated in mpn to fill the field.
Where the value comes from on a connected store
| Shopify | FeedRobin reads no MPN from Shopify and does not use the variant’s SKU. An mpn is sent only when the sheet on the Corrections page or a feed rule sets one. |
|---|---|
| WooCommerce | Not sent; the plugin never treats the SKU as a manufacturer part number. |
The free feed check reads this attribute from any feed file and reports the defects above; every check is listed.
Questions merchants ask
What is the difference between SKU and MPN?
A SKU is your code, chosen by you, unique in your shop. An MPN is the manufacturer’s code, the same in every shop that sells the product. Only the second identifies the product outside your store.
What if my own-brand products have no part numbers?
Then leave mpn empty, and if they have no GTIN either, set identifier_exists to false.
Is mpn needed with a GTIN?
No. A GTIN is sufficient on its own.
Sources
- MPN [mpn] — Google Merchant Center Help
- About unique product identifiers — Google Merchant Center Help