Google Shopping drives more e-commerce revenue than any other ad format. How it works, how to set it up, and how to optimise your feed for results.
How Google Shopping Works
Unlike search ads where you bid on keywords, Shopping ads are triggered by your product feed — a structured data file you submit to Google Merchant Center that describes your products: title, price, image, category, GTIN, and more.
Google matches your feed to relevant searches. The quality and completeness of your feed determines which searches you appear for, and how often. Getting your feed right is the single most impactful thing you can do for Shopping performance.
What a Good Product Feed Looks Like
Titles matter most. Google uses your product title as the primary signal for matching to search queries. Structure titles as: Brand + Product Type + Key Attributes. “Nike Air Max 270 Men’s Running Shoes Size 10 White” will match far more relevant searches than “Nike Shoes.”
Images must be clean. White or neutral backgrounds, product filling at least 75% of the frame, no watermarks or promotional text overlays. Poor images get your products suppressed.
Prices must match your site. Any discrepancy between feed price and landing page price triggers disapproval. Keep feeds updated — stale prices from a feed that updates only weekly are a common source of Merchant Center suspensions.
GTINs (barcodes) increase reach. For branded products, including the correct GTIN significantly increases impressions because Google can match your product to its knowledge graph.
Campaign Structure
Standard Shopping vs Performance Max: Standard Shopping gives you more control — you can set bids at the product group level, exclude search terms, and see impression share data. Performance Max is more automated but less transparent.
For accounts with solid conversion data, Standard Shopping campaigns with manual CPC or Target ROAS bidding tend to give clearer optimisation levers. Performance Max makes more sense once Standard Shopping is established and you want to capture additional inventory.
Segmentation by margin: Not all products have the same profit margin, but Google doesn’t know that. Create separate campaigns for high-margin and low-margin product groups so you can set different target ROAS by tier. Chasing a 4x ROAS on a 10% margin product and a 10% margin product in the same campaign means one is being under- or over-invested.
Bid Strategy Considerations
Start with manual CPC if you don’t have conversion data yet — you need at least 30–50 conversions per month before automated bidding strategies have enough signal to work reliably.
Once data is established, Target ROAS bidding can be effective but requires patience during the learning phase. Set your initial ROAS target at or near your current actual ROAS, then adjust gradually rather than setting an aggressive target immediately.
Negative Keywords Still Matter
You can’t add keywords to Shopping campaigns, but you can add negative keywords to prevent your ads showing on irrelevant searches. Common additions: competitor brand names (unless you deliberately want conquest traffic), “free,” “DIY,” “how to,” “review,” and category terms that are too broad for your specific products.
In Short
- Feed quality is the primary lever — titles, images, prices, and GTINs drive performance
- Structure campaigns by product margin, not just by category
- Start with manual CPC, switch to Target ROAS once you have 30–50 monthly conversions
- Negative keyword lists prevent wasteful spend and sharpen targeting
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