How Performance Max works

You give Google products from Merchant Center, text, images, video and a goal such as conversion value. The algorithm decides where and to whom to show ads. That is why results depend almost entirely on the quality of the data you provide.

1. The product feed is the foundation

  • Clear product titles with key attributes: type, brand, model, size, color.
  • Prices and availability in the feed match the website.
  • Quality photos without watermarks or extra text.
  • Categories, brand and, where possible, GTIN are filled in.
  • No disapproved products in Merchant Center, or very few.

2. Purchase tracking with value

The purchase event should send the amount, currency and a unique order ID. Then Google knows which sales bring more money and does not count one order twice. Once a month, compare the number of orders in the store admin, GA4 and Google Ads: a small gap is normal, a large one means you should look for an error.

3. Asset group structure

One campaign for the whole catalog is the simplest option, but not the best. It is better to split products by business logic: by category, margin, or bestsellers versus the rest. Then you can give more budget to what brings profit, not just revenue.

4. Audience signals and search themes

Audience signals do not limit delivery; they tell the algorithm where to start: your customers, site visitors, interests, search themes. They are often skipped, yet for a new campaign they noticeably speed up learning.

5. Negative keywords and brand exclusions

In Performance Max you can add negative keywords at the campaign or account level. They apply to Search and Shopping. There are also brand exclusions, for example if you do not want to pay for searches with your own store name that already come in free from organic search.

What to check every week

  • ROAS and cost per conversion for each campaign, not just overall numbers.
  • The search terms report and search term categories.
  • Which products get impressions and sales, and which spend budget with no result.
  • Disapproved products in Merchant Center.
  • Whether the campaign is limited by budget or by the ROAS target.

What not to do

  • Do not change the bidding strategy and budget every couple of days: the algorithm needs time to learn.
  • Do not judge the campaign by its first week.
  • Do not launch Performance Max before purchases are tracked correctly.

FAQ

How long does Performance Max take to learn?

Usually a few weeks. Results can fluctuate during learning, so big decisions are better made once data has built up.

Can Performance Max run alongside regular Search campaigns?

Yes. If a Search campaign has an exact match keyword identical to the search, it usually takes priority. This helps you keep control of important searches.

Which is better for a store: Performance Max or a standard Shopping campaign?

It depends on the feed, budget and data. Performance Max gives more reach, a standard Shopping campaign gives more control. They are often tested side by side.

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