A product feed is a file in which an online store passes its product list to other systems in a machine-readable form: title, description, price, availability, link, image and more. Google Merchant Center reads it, and through it Shopping ads and Performance Max, as do price comparison sites and Meta’s catalog.
A product feed is a structured, machine-readable list of an online store’s products. Every product carries the same set of fields — an ID, title, description, price, availability, link and image. Ad platforms and comparison sites read it to learn what you sell and at what price.
The feed is usually generated by the store platform or a plugin and published at a URL that Merchant Center or a comparison site fetches on a schedule. Without a feed there are no product ads: neither Google Shopping nor Performance Max has anywhere else to get a product’s price and photo from.
An XML feed is a text file in which every field sits in its own tag. Google uses RSS with a g: namespace. Regional comparison sites often have their own spec — the Czech ones, Heureka and Zboží.cz, wrap every product in a SHOPITEM tag. The data is the same, just named differently, which is why stores usually keep a separate feed for each channel.
<g:title>…</g:title> | Product title, 150 characters max. Also required: id, description, link, image_link, availability and price. | |
| Heureka | <PRODUCTNAME>…</PRODUCTNAME> | The same field in Heureka’s tag. Price goes in PRICE_VAT, including VAT. |
| Custom label | <g:custom_label_0>margin-high</g:custom_label_0> | Example: a margin label used to split products into campaigns. |
Custom labels (custom_label_0 to 4) are the most valuable part of the feed for advertising. Each value can be 1–100 characters, with up to 1,000 unique values per label. They let you split a campaign by gross margin, season or bestsellers, and read performance in a way your category tree never shows.
The title decides which searches a product shows for and whether anyone clicks. Paste a product title from your feed and see whether it passes Google’s rules.
The checker applies rules from the Merchant Center documentation: a 150-character limit, no price, sale or shipping in the title, and no capital letters for emphasis. Google also notes that people usually notice only the first 70 characters or fewer, so the product type and its key attribute belong at the start.
A good feed is one where products aren’t disapproved and ads sell what actually makes money. In practice that comes down to five things:
If your store sends products to Google through an API, check with your provider that it has moved to the Merchant API. Google sunset the old Content API for Shopping on 18 Aug 2026.
One catalog, several feeds. Each channel reads a slightly different format and enforces different rules.
| Destination | Format | Watch out for | What it powers |
|---|---|---|---|
| Google Merchant Center | XML (RSS), TSV, Google Sheets, Merchant API | Title up to 150 characters, price matching the site, GTIN | Shopping ads, Performance Max, free listings |
| Meta catalog | CSV, TSV or XML | Product IDs matching the pixel for dynamic ads | Catalog ads on Facebook and Instagram |
| Heureka | XML to Heureka’s spec | EAN and parameters for product matching | Price comparison (Czechia, Slovakia) |
| Zboží.cz | XML to Seznam’s spec | Its own required fields and categories | Seznam’s price comparison (Czechia) |
Terms that sit next to the feed in every product account.
On the site, “Ralf” is enough, because the photo, category and menu sit around it. In search results the title stands alone, and Google matches queries against it. A product without its type and attributes in the title shows less often and for vaguer queries, which also drags down CTR.
Without labels you can only split a campaign by the store’s categories, and those rarely line up with margin. The result is one campaign with one target ROAS for products with 15% and 45% margins. A margin label is the cheapest preparation for splitting PMax sensibly.
When the feed refreshes once a day and the store changes prices or stock more often, ads show the wrong price or sold-out products. Google disapproves those products, and people who click don’t buy. If prices or stock change during the day, send updates through the API or turn on automatic item updates in Merchant Center.
A product feed is a file in which an online store passes its product list — title, description, price, availability, link and image — to other systems. Google Merchant Center, Meta’s catalog and price comparison sites all take products from it.
Essentially yes. Product feed is the general name for the file with your products; XML is the most common format stores use to send it. Google also accepts TSV text files, Google Sheets and a Merchant API connection.
150 characters at most. Google notes that people usually notice only the first 70 characters or fewer, so the product type, brand and key attribute belong at the start. Price, sale and shipping information don’t belong in the title.
Custom labels custom_label_0 to 4 tag products by whatever your ads need: margin, season, bestsellers or price band. You then use them to split products into campaigns and groups with their own targets and reporting.
At least as often as prices and stock change on the site. For most stores a daily fetch is enough. If prices or stock change during the day, send updates through the Merchant API or turn on automatic item updates, which take price and availability straight from the site.
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