How to improve the product data behind your Shopping ads: titles that match real searches, images and identifiers that keep products live, and labels for margin-based bids.
In Google Shopping there are no keywords to choose. Google decides which searches your products appear for, and how they look next to competitors, largely from the product data you send through Google Merchant Center. Yet many shops treat that feed as a technical task: a connection that either works or doesn't, set up once and left alone.
Feed optimisation means improving that product data (titles, descriptions, images, identifiers, categories and custom labels) so your products appear for the right searches, earn the click and can be bid on according to what they actually earn you. Because better data helps every product on every search at once, it is often one of the cheapest improvements available in Shopping, and it doesn't require raising a single bid.
This article covers why the feed does the job keywords do elsewhere, how to write titles that match real searches, what keeps products serving, how custom labels let you bid on margin rather than revenue, and a weekly routine to keep it all healthy. Everything here also applies to Performance Max campaigns that use your feed.
In a Search campaign, you choose keywords and write ads. In Shopping, and in Performance Max campaigns that use a product feed, Google builds the ad from your data: the title becomes the headline, the image is the creative, and the price, your shop name and, where available, delivery details and ratings sit underneath. To decide which searches to match, Google reads your titles, descriptions, categories and other attributes.
In Shopping, your product feed is your keyword list, your ad copy and your bidding signal at once. A product titled "Classic Tee" gives Google two words to match against. "Men's Organic Cotton T-Shirt, Navy, Crew Neck" gives it the words people actually search with, and tells a shopper at a glance whether it is what they want.
The same data also feeds free listings, the unpaid product results Google shows on the Shopping tab and elsewhere, so improvements pay off twice. A weak feed, by contrast, limits every campaign built on it, however good the bidding.
In Shopping, your product feed is your keyword list, your ad copy and your bidding signal at once.
Of all the attributes, titles usually have the most influence on which searches you appear for and whether people click. Google allows up to 150 characters, but shoppers often see only the start, so put the words that matter first: the product type and the attributes buyers search with. Add your brand at the start if people search for it by name, and further back if they don't. Which attributes matter depends on the category:
Use the words your customers use, not your internal names. A range called "Aurora" means nothing to someone searching for "linen duvet cover king size". The search terms report for your Shopping campaigns shows the searches your products appeared for; if obviously relevant searches are missing, the words are probably missing from your titles.
Titles are not the only text Google reads. Use the description, which can run to 5,000 characters, for materials, dimensions, compatibility and use in plain sentences rather than keyword lists. Fill in the optional attributes that describe the product, such as colour, size, material and gender, because Google uses them to match searches and filters, and for clothing some of them are mandatory in several major markets.
If you sell in several countries, each one needs titles and descriptions in the local language, written for local search habits rather than machine-translated without review. You don't need to rename products on your website to do any of this: rules in Merchant Center, a supplemental feed or a feed management tool can rewrite titles for Google while your shop keeps its own naming.
Your main image has to stand out in a row of similar products and follow Google's rules. Promotional text, watermarks and borders aren't allowed on it and can get products disapproved, and Google recommends a plain white or light background with the product clearly visible. Use lifestyle photos as additional images, and if you think a different main image style would earn more clicks, test it on a group of products before changing everything.
Prices and availability in the feed must match your product pages, including the currency. Mismatches are a frequent cause of disapprovals, typically because a promotion changed on the website but not in the feed, or because the feed updates once a day while stock changes by the hour. Update your feed at least daily, more often if prices or stock move during the day; structured product data on your pages lets Merchant Center correct some mismatches automatically, but treat that as a safety net.
Product identifiers matter more than they look. Where a manufacturer has assigned a Global Trade Item Number (GTIN), in Europe usually the 13-digit European Article Number (EAN) printed under the barcode, include it: Google uses it to identify exactly which product you sell, and products without one can be limited. For products you make yourself, provide your brand and a manufacturer part number (MPN), or state that no identifier exists.
Finally, set your shipping costs and return policy in Merchant Center. Delivery costs and return terms can appear alongside your listing, and when several shops sell similar products at similar prices, they are often what decides the click.
Merchant Center gives you five custom label fields, numbered 0 to 4, which you can fill with any values you like. Shoppers never see them; they exist so you can group products for bidding and reporting. Many shops leave them empty, which means every product is bid on as if it were worth the same to the business.
Here is why that matters. Say you sell two products at €100 each, one with a gross margin of 60% and the other with 20%. At a return on ad spend (ROAS) of 500%, meaning €5 of revenue for every €1 of advertising, you spend €20 to make each sale: on the first product you keep €40, on the second you keep nothing.
A simple rule follows: your break-even ROAS is 1 divided by your margin. At a 60% margin, break-even is about 167%; at 20%, it is 500%. Put each product's margin band into a custom label, such as high, medium and low, split the bands into separate campaigns, and give each its own ROAS target.
Use the margin after product cost, shipping and payment fees if you can calculate it, because that is what you actually keep. If your shop platform can't export margins, a simple supplemental feed listing each product's ID and its label, updated monthly, is enough. Other useful labels mark best-sellers, seasonal products, clearance items and new arrivals that need budget to gather data; keep the system small enough that someone actually maintains it.
Feed problems rarely announce themselves. A disapproval email is easy to miss, and in Google Ads it simply looks as if fewer products are getting impressions. Fifteen minutes a week catches most problems before they cost you sales: