In traditional search advertising, keywords are everything. You choose the words, set bids, and control what triggers your ads. In Google Shopping and Performance Max, that logic is turned on its head. There are no keywords. Instead, Google uses your product feed to decide when and where your products appear.
This means your feed isn't just a data export — it's your keyword strategy, your ad copy, and a significant input into your auction competitiveness, all in one. And most ecommerce businesses are leaving significant money on the table because they treat it like an afterthought.
When a user searches on Google, the Shopping algorithm matches their query against the product data in Merchant Center feeds. It looks primarily at product titles, descriptions, product types, and Google product categories to determine which products are relevant — then factors in bid, landing page, and historical performance to decide which ads to show and in what position.
Think of your product title as the equivalent of a keyword. A vague or generic title limits which searches your product can match to. A well-structured, descriptive title expands your eligible auction pool and attracts more relevant, higher-intent traffic.
Key insight: Google can only match your products to searches based on the information you provide in your feed. If a critical attribute is missing or poorly written, Google doesn't guess — it simply excludes your product from those auctions.
Product titles in Shopping campaigns should be written with search intent in mind, not just product cataloguing conventions. The most effective formula for most product categories is:
Brand + Product Type + Key Differentiating Attribute(s)
For example:
The attributes you include in the title should reflect what your target buyers actually search for. For apparel, that's often colour, size, and material. For electronics, it might be specs like storage capacity or screen size. For consumables, it might be quantity or pack size.
Tools like SEMrush and Search Engine Land's Shopping guides can help you research what terms buyers use in your category — and these should feed directly into your title optimisation strategy.
Beyond titles, there are several feed attributes that significantly affect performance:
| Attribute | Status | Impact |
|---|---|---|
| GTIN (Global Trade Item Number) | Required | Enables Google to match your product to exact search queries; improves auction eligibility |
| Product Title | Required | Primary matching signal — quality directly impacts which queries trigger your ads |
| Product Description | Required | Secondary matching signal; also used in AI product discovery and Performance Max |
| Google Product Category | Recommended | Helps Google classify your product; affects eligibility for category-specific promotions |
| High-quality images | Required | Main image on white/light background; affects CTR and product approval status |
| Custom Labels | Recommended | Used to segment products for bidding — by margin, season, sale status, etc. |
One of the most commonly overlooked feed issues is product disapprovals. If Google Merchant Center flags a product as disapproved — for reasons like missing GTINs, policy violations, incorrect pricing, or landing page mismatches — that product receives zero impressions, regardless of how high your bid is.
Regularly auditing your Merchant Center diagnostics tab is essential. Common disapproval reasons include:
Log into Google Merchant Center and navigate to Diagnostics. If you see a significant number of item-level issues, resolving these alone can unlock meaningful new impressions without changing a single bid.
Custom labels (you have five available: 0–4) allow you to add your own categorisation to products in the feed. These labels don't affect ad matching, but they allow you to segment products within your campaigns — and apply different bids or strategies to different groups.
Common uses for custom labels include:
If you're running Performance Max campaigns for ecommerce, your feed quality is even more critical. Performance Max uses your product feed as the primary input for Shopping placements — but it also uses product images, titles, and descriptions to generate ad creative across Display, YouTube, and other channels.
A feed with rich, descriptive content and high-quality images gives Performance Max significantly more to work with when generating creative. A thin feed — minimal titles, generic descriptions, low-resolution images — constrains what the campaign can do across all channels, not just Shopping.
Feed optimisation can feel overwhelming if your catalogue has thousands of products. The most efficient approach is to start with your highest-revenue or highest-margin products and work outward.
For each priority product, review:
Even modest improvements to title quality and GTIN coverage on your top 20% of products can produce meaningful ROAS improvements — often without increasing budget at all.
Search Engine Land — Shopping feed optimisation guides · SEMrush — Product listing ad strategy · Google Merchant Center Help — Official feed specification and requirements
Common questions about this topic.
Your product feed is the data source Google uses to match your products to search queries. Poor feed quality — vague titles, missing attributes, incorrect prices, or disapproved products — reduces how often your products appear and to whom. Higher-quality feeds give Google more data to match your products to relevant searches, leading to better impression share, higher click-through rates, and improved ROAS.
The highest-impact feed attributes are: title (must include brand, product type, and key variant), GTIN or MPN (required for branded products), price and availability (must match your website exactly), product_type or google_product_category (improves relevance matching), and description (supports keyword matching). Missing or incorrect GTINs are the single most common cause of product disapprovals.
Effective Shopping titles follow the structure: Brand + Product Type + Key Attribute(s). Place the most important terms first. Include colour, size, material, or model number when they're relevant to how customers search. Avoid promotional text ('Best!', 'Sale!'), keyword stuffing, and ALL CAPS. Titles should be 70–150 characters. Test different title structures using feed management tools to measure impact on impressions and clicks.
Google recommends updating your feed at least daily for pricing and availability. Out-of-date data — particularly mismatched prices between your feed and website — triggers disapprovals and account warnings. For large catalogues, use the Content API or a scheduled feed fetch via URL to automate updates. Static feed uploads (manual CSV) are only suitable for catalogues with infrequent price or stock changes.
The most damaging feed issues are: product disapprovals (items not showing at all), price mismatches (leads to account warnings), missing GTINs for branded products (reduces visibility), and vague titles that don't match search intent. Run a regular Merchant Center diagnostics review to catch these issues before they compound. A single batch of disapprovals can silently cut impressions by 20–40% for affected product categories.
I audit product feeds and identify the specific issues affecting your Shopping and Performance Max performance — with a clear action plan for fixing them.
See Product Feed Optimisation →