Short answer
- Accurate data first: price, availability and links in the feed must match your product pages, or products can be disapproved.
- Titles do most of the work: put what the product is and its key attributes up front.
- Use real identifiers: correct GTINs where they exist. Never invent them.
- Clean main images that clearly show the product, then add extra images.
- The source of truth is Google's product data specification. Check it, because requirements change.
How the feed becomes an ad
You (or your store app) send product data to Google Merchant Center: title, description, price, images, availability and more. Google uses it to decide which searches each product can match, and to build the ad people see. There are no keywords to choose in Shopping the way there are in Search ads, so the feed is effectively your keyword list and your ad copy in one.
Shopify stores can connect through Shopify's Google channel app, which syncs products to Merchant Center. Shopify documents the Google channel setup.
Titles
Google allows titles up to 150 characters, but only the first part is likely to show, so the start matters most. A practical order for many stores:
| Product type | Pattern | Sample (fictional) |
|---|---|---|
| Apparel | Brand + product + gender + material + color + size | Northline Women's Merino Wool Hiking Socks, Grey, M |
| Home goods | Brand + product + material + size + color | Oakhaus Solid Oak Chopping Board, 40 x 30 cm, Natural |
| Beauty | Brand + product + key feature + size | Bloomwell Unscented Body Lotion for Dry Skin, 250 ml |
| Parts and supplies | Brand + product + model or compatibility + spec | Fixpro Replacement Filter for X200 Vacuum, 2-Pack |
- Describe the product, not the promotion. "SALE!!" and "free shipping" don't belong in titles.
- Use the words customers search, not internal names. "Burgundy" may beat "Merlot Dream" as a color.
- Keep variants distinct, so a size M and size L aren't identical titles.
GTIN, brand and MPN
A GTIN is the barcode number for a product (such as a UPC or EAN). For branded products that have one, supplying the correct GTIN helps Google understand exactly what you sell.
- Use the manufacturer's real GTIN. Never make one up or reuse one from a different product.
- Products without a GTIN, like handmade or custom items, follow different rules, often using brand and MPN where available. Check Google's spec for the right approach.
- Brand should be the actual brand, consistent across all products.
Mismatched or invalid identifiers are a common reason products show limited performance or warnings in Merchant Center.
Images
- Main image: the product itself, clearly visible, usually on a plain background. Google sets minimum sizes in its spec. Larger, sharp images are safer.
- No promotional overlays like "50% off" or watermarks on the main image.
- Extra images: angles, scale, in-use shots. They help shoppers once they click.
- One image per variant where colors differ, so the red one shows red.
Price, availability and landing pages
This is where small stores get disapproved most often. Google checks that what you submit matches what people see on your site.
| Check | Common mistake |
|---|---|
| Price matches the product page | A sale ended on the site but the feed still shows the sale price |
| Availability matches | Out of stock on the site, "in stock" in the feed |
| Link goes to that exact product | Links to a collection page or the homepage |
| Currency and shipping are correct | Shipping costs not set up for the target country |
| Page works on mobile | Pop-ups that block the product on phones |
Automatic syncing from your store platform prevents most of these. Manual spreadsheet feeds drift out of date quickly.
Attributes worth filling in
- Product type: your own category path, useful for organizing campaigns.
- Google product category: where it applies, helps Google classify items.
- Color, size, material, gender, age group: required for some categories, such as apparel, and helpful for matching.
- Custom labels: your own tags, like "best seller" or "high margin", to group products in campaigns.
- Description: accurate, useful detail. Not a copy of the title.
Fixing Merchant Center problems
- Open the diagnostics or products section and sort issues by how many products they affect.
- Fix account-level issues first (site verification, shipping, policies), since they can affect everything.
- Then fix the most common product-level issue, usually price, availability or identifiers.
- Fix at the source (your store) rather than patching the feed, so it stays fixed.
- Re-check after the next sync. Google explains how to handle product data quality issues.
A clean feed is the foundation for Shopping and Performance Max campaigns. If you'd like help, feed clean-up and Shopping campaigns are part of ecommerce & Shopify marketing, quoted after a free audit.