Performance Max (PMax): definition, how it works and benchmarks

What a Performance Max campaign is, where it runs, what the algorithm decides for you, what you have to feed it, the results to expect and the traps

The essentials

  • Definition: Performance Max is a Google Ads campaign type that runs automatically across search, Shopping, YouTube, Display, Discover, Gmail and Maps, from a conversion objective and a set of assets.
  • What the algorithm decides: the networks, the bids, the audiences, the combinations of headlines, images and videos; the advertiser supplies the objective, the budget, the assets and the signals.
  • 2026 benchmarks: 60 to 70% of online retailers' Google Ads spend; a ROAS of 3 to 8 on a catalogue, a variable cost per lead in lead generation.
  • Prerequisite: reliable conversions with a value, a clean product feed, at least 30 conversions a month, and brand terms excluded so you can read new business.

Performance Max (PMax) is a Google Ads campaign type, launched in 2021, that runs ads across all of Google's networks (search, Shopping, YouTube, Display, Discover, Gmail, Maps) from a conversion objective, a budget and a set of assets supplied by the advertiser. The algorithm chooses the placements, the bids, the audiences and the combinations of headlines, images and videos. It is today the default campaign for e-commerce and a frequent complement in lead generation. How Google Ads works in general is set out in Google Ads: definition and how it works.

What the advertiser supplies and what the algorithm decides

The advertiser suppliesThe algorithm decides
The objective (sales, leads, value) and the conversions to optimiseThe networks and placements
The daily budget and the bidding strategy (target ROAS, target CPA, maximise)The bid at every impression
The asset groups: headlines, descriptions, images, logos, videosThe combinations and formats
The product feed (Merchant Center) for retailWhich products are promoted
Audience signals (customer lists, visitors, interests) and search themesThe audiences actually targeted, beyond the signals
Exclusions (brand, placements, areas)Everything else

When Performance Max fits

  • E-commerce with a catalogue: PMax replaced smart Shopping campaigns; this is the main use case, accounting for 60 to 70% of retailers' Google Ads spend in 2026. How to run it is covered in SEA and e-commerce.
  • As a complement to a search campaign: to capture impressions on networks where the advertiser isn't present, once search is properly structured.
  • Lead generation with volume: at least 30 conversions a month and qualified conversions (reconciled with the CRM), otherwise the algorithm optimises towards low-quality forms.
  • Local objectives: store visits, calls, directions, with the Google Business Profile listing linked.

PMax suits low-volume accounts (fewer than 30 conversions a month) badly, as well as complex B2B sales with no conversion value, and advertisers who need control over their search terms.

The 2026 benchmarks

ContextTypical resultNote
E-commerce, catalogue, target ROASROAS 3 to 8Brand often accounts for 30 to 50% of the ROAS displayed
Lead generation, target CPACost per lead close to search, quality more variableInsist on qualified conversions
Learning phase4 to 6 weeksDon't change budget or objective by more than 20% during that period
Network splitMostly Shopping and search in retailVisible in the channel reports since 2025

The prerequisites for PMax to work

  1. Reliable conversions with a value: a purchase with an amount, or leads valued by quality; the algorithm optimises whatever you give it. Automated bidding is explained in automated Smart Bidding.
  2. A clean product feed: descriptive titles, compliant images, up-to-date prices and stock, categories filled in; see Google Shopping.
  3. Complete assets: 15 headlines, 5 descriptions, images in all three formats, at least one video (otherwise Google generates one, often a poor one).
  4. Audience signals: customer lists, converted visitors, search themes; they speed up learning without restricting delivery.
  5. Exclusions: brand terms excluded (or a separate brand campaign) so you can measure new business, unsuitable placements, content categories.
  6. Structure: one campaign per major product family or per objective, not a single campaign for everything; see structuring a Google Ads account.

The limits and the traps

  • Brand counted as new business: without exclusions, PMax captures searches on the company's name and shows a flattering ROAS.
  • Opacity: the reports by channel, search term and placement have improved since 2024 but remain partial.
  • Cannibalisation: PMax takes priority over standard Shopping campaigns and can take traffic from search campaigns on the same queries.
  • Low-quality leads: in lead generation with no conversion value, the algorithm finds the cheapest forms, not the best ones.
  • Frequent changes: every significant change restarts the learning phase.

The metrics to track are covered in the Google Ads KPIs.

Our advice: before judging a Performance Max campaign, exclude brand terms and read its ROAS or cost per lead in GA4 or your CRM, not in Google Ads. In most small business accounts, that double correction halves the ROAS on display; it is on that corrected figure that the budget is decided — and it is often still good.

How GreenRed helps

Rather than juggling several tools, GreenRed's Google Ads module brings these metrics together in a single dashboard, compares them over time and tells you which actions come first. You can try it free, with no card, from the Pricing.

Frequently asked questions

What is a Performance Max campaign?

A Google Ads campaign type that runs automatically across all of Google's networks (search, Shopping, YouTube, Display, Discover, Gmail, Maps) from a conversion objective, a budget and assets supplied by the advertiser. The algorithm chooses the placements, the bids, the audiences and the asset combinations.

Does Performance Max suit a small business?

Yes for an online store with a catalogue and reliable conversions, or for an account generating at least 30 qualified conversions a month. No for a low-volume account, a complex B2B sale with no conversion value, or an advertiser who needs control over their search terms.

What ROAS should you expect from a Performance Max campaign?

Between 3 and 8 in e-commerce depending on margin and sector, as displayed by Google Ads. That figure often includes 30 to 50% of sales on the brand name; you need to exclude brand terms and read the results in GA4 or your CRM to know the real new-business ROAS.

What do you need to supply for a Performance Max campaign to work?

Reliable conversions with a value, a clean product feed for retail, complete assets (15 headlines, 5 descriptions, images in all three formats, a video), audience signals (customer lists, visitors), exclusions (brand, placements) and 4 to 6 weeks of learning with no major changes.

From theory to practice

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