What is product identifier?
A product identifier is a value that tells a shopping platform exactly which product your listing refers to, made up of the brand plus a barcode or a manufacturer part number.
Worked example, not a result
Two different rules in one catalogue
Say a store lists 2,100 items. Of those, 1,925 are branded goods bought in from other manufacturers, and 175 are made for the store under its own name.
The two groups need opposite treatment. For the 1,925 resold items, the manufacturer has assigned a barcode, so the brand and that number both belong in the feed exactly as issued. Leaving them out means the listing cannot be matched to the product other retailers are selling, and the searches that name a specific model go elsewhere.
For the 175 own label items, no barcode exists and none should be invented. The correct answer is to declare that no identifier exists and supply the store's brand name with a part number of its own. That is an honest statement rather than a workaround, and platforms handle it properly.
Getting the split right is a one time job per product type. The counts above are an example.
Why it matters
Identifiers decide whether your listing is understood as a specific product or as an anonymous item. That distinction controls eligibility for the highest intent searches available in ecommerce, the ones where someone types an exact model name, so it sits right at the front of the visitors lever.
They also affect conversion in a quiet way. Listings matched to a known product are shown alongside the right competitors, in the right filters and with the right specification, so the shopper arriving on your page already believes they are in the right place.
For a store owner the useful framing is that identifiers are inventory data, not marketing data. Collect them when a product is created, store them in proper fields rather than in the description, and every downstream use, from shopping feeds to marketplace listings to on site search, works without another project.
Common mistakes
- Storing identifiers in the product description. Free text cannot be mapped to a feed field, so the value exists on the site and is invisible everywhere it is needed.
- Declaring that no identifier exists across the whole catalogue to silence warnings. Products that do have one are then matched to nothing and lose the searches that named them.
- Ignoring brand as part of the identity. A part number without a brand identifies nothing, and a missing brand also removes the product from brand filters.
- Sharing one identifier across variants. Sizes and colours with their own barcodes each need their own value, otherwise the whole set collapses into one item.
Related terms and answers
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