What is really behind that row of tiles

You type "kettle 1.7 litres" into the search box, and before the usual blue links appear, you see a row of tiles with a photo, a price and a shop name. These are shopping ads, also known as product ads: paid advertising slots fed by a retailer's data feed, which work differently from an ordinary text ad or an organic search result.

If you take these tiles for a neutral list of the best offers, you are confusing two different things: an advertising space a retailer pays for, and an independent ranking by price or quality. The two can overlap, but they do not have to.

The individual tiles contain more information than a classic text ad: an image, a price, often a star rating and sometimes a note about delivery costs. That is exactly what makes them look more trustworthy at first glance than a pure advertising space really should.

Where the image, price and title in the ad come from

For shopping ads, a retailer does not maintain each ad by hand. Instead, it supplies the search engine with a list of item data: title, image, price, availability and often the delivery costs, bundled together in what is called a product data feed. This feed is usually generated automatically from the shop system and uploaded again at regular intervals, not immediately every time a price changes.

Errors in this feed, a missed update or a wrongly entered delivery charge, directly affect what you see in the ad, without the retailer necessarily noticing. So the tile shows what is in the feed, not necessarily what is on the product page right now.

How the order of the ads is decided

The order of the tiles is not a simple price list from cheapest to most expensive. It results from a mix of the bid the retailer is willing to pay per click and how well the feed data matches the search you entered. A retailer with a higher bid can therefore appear further up than a cheaper seller who pays less for the ad position.

That does not mean expensive ad slots automatically show expensive products. It just means that the position in the row is not in itself a reliable price signal, in the way you might expect from a sortable comparison table.

The price shown is not automatically the final price

Say you see two ads for the same kettle. Ad A shows 39.99 euros but charges an extra 4.95 euros for delivery, making 44.94 euros in total. Ad B shows 42.50 euros but offers free delivery on orders over 40 euros, so for the single kettle you actually only pay 42.50 euros. At first glance A looks cheaper, but in the end B is the lower total price.

This difference is barely noticeable in the tile overview, because delivery costs are often shown in small print there or not at all. Only a click into the shop and a look at the basket total shows which ad is actually the cheaper one.

Star ratings and extra details in the tile

Some ads also show a star rating under the price. This rating comes either from the same data feed or from a separately connected review service, and it usually refers to the shop as a whole, not necessarily to this one product. A high star rating next to an ad is therefore no substitute for checking the reviews of the exact item you want to buy.

How they differ from standalone price comparison sites

Besides the tiles directly in the search results, there are standalone price comparison sites that list several shops for a product side by side, often with their own search and filter functions. These sites also usually work with their own data feed from retailers and earn a commission per click or per sale, much like a shopping ad itself. The main difference is where the list appears: as an advertising slot right in the search engine, or as a separate site that you switch to first.

For you as a basis for comparison, that changes little about the basic rule: a ranking on a standalone site is also, first of all, a selection of participating shops, not automatically a complete overview of the whole market. The article How price comparison sites really rank offers explains this mechanism in detail and shows what else to look out for.

How to use shopping ads sensibly for comparing

The tiles are a good starting point for quickly seeing several sellers for a product, but they should not have the final say when you compare prices.

• Open several ads and compare the actual basket total including delivery, not just the price shown in the tile.
• Check that it really is the same variant, such as the same colour or capacity, and not a similar but cheaper model.
• For reviews, rely on the information on the product page itself, not just on the star under the ad.
• Also take a look at our categories before you decide on one of the shops shown.

The article on dynamic pricing explains why the amount shown in an ad can change within a few hours. Knowing how to spot fake or paid-for reviews also helps you judge the star symbol next to the ad. And knowing how to tell a genuine pricing error from a bait offer is useful too when a tile looks strikingly cheap.

Frequently asked questions

Are shopping ads automatically the cheapest offers?

No. The order results from bids and how relevant the feed data is, not from price alone. An offer higher up can still be more expensive than one that only appears further down.

Why does the price in the ad sometimes not match the product page?

Because the ad is based on a data feed that is not updated immediately every time the price changes. Some time can pass between a price change in the shop and the feed being updated.

Does the star rating next to the ad refer to the product or the shop?

Usually to the shop as a whole, not necessarily to this one product. To judge the specific item, it is worth looking at the reviews directly on the product page.

Why should I still do the maths myself even if delivery costs are shown?

Because delivery costs are often shown in small print or hidden altogether in the tile overview. Only the total in your basket reliably shows which seller is actually cheaper in the end.