TL;DR, the core in 5 points
• PMax distributes one campaign across all Google inventory, less control, more scale, but only worthwhile at 30+ conversions/month.
• Setting up asset groups correctly (including your own video) is the difference between PMax that works and PMax that burns money.
• Audience Signals are hints to Google's AI, not hard targeting, entering your best customer lists accelerates the learning phase.
• Negative keywords and brand exclusions are not available by default in the UI: you need to actively request or configure them.
• Conversion tracking must be 100% correct. PMax is only as good as the data it receives.
What is Performance Max?
Performance Max (PMax) is Google's AI-driven campaign type that distributes one campaign across all Google inventory (Search, Display, YouTube, Discover, Maps, Gmail). Less control, more scale.
Introduced in 2021 as a replacement for Smart Shopping and Local campaigns, PMax in 2026 is the standard for advertisers who want to reach scale quickly. The system automatically optimises toward goals: conversions, conversion value or store visits. The pitfall: 'automatic' means that errors in conversion tracking or poor assets are automatically amplified. PMax is an amplifier, it makes good campaigns better and bad campaigns more expensive faster.
Expected impact: with correct setup, 15–40% more conversions versus equivalent budget across separate campaign types. Time investment: 8–16 hours for initial setup + weekly check of 30–60 min.
Tips 1–3: Setting up asset groups
Maximum 15 headlines, 5 long headlines, 5 descriptions, 20 images, 5 videos. No video? Google auto-generates one from your images, usually bad. Better: add one simple video yourself.
Asset diversity is critical: use all 15 headline slots with variations in proposition (price, speed, result, guarantee). Headlines must also stand alone. Google combines them dynamically. Don't write headlines that only make sense together. For images: at least one landscape (1200×628), one square (1200×1200) and one portrait (960×1200) per asset group. A simple 30–60 second 'talking to camera' video always beats Google's auto-generated version, and can be made in 2 hours with a phone.
Expected impact: full asset coverage raises asset quality score to 'Excellent', which correlates with 20–30% lower CPA. Time investment: 4–6 hours for complete asset group setup.
Tips 4–6: Audience Signals (not targeting)
Audience Signals are 'hints' to Google's AI, not hard targeting. Add your best customer lists, in-market segments and custom audiences. Speed-up period 2–4 weeks.
The distinction between Audience Signals and targeting is crucial: Google uses your signals as a starting point but moves outside them if it sees better opportunities. Provide the most qualified signals: customer list of closed deals (not leads), website visitors who stayed more than 2 minutes, custom audience based on competitor website visitors. A too-narrow signal list slows the learning phase. A too-broad one (e.g. 'all website visitors') gives little direction. Ideal list size: 1,000–10,000 active customer records.
Expected impact: quality Audience Signals shorten learning phase from 4 weeks to 2 weeks with sufficient volume. Time investment: 2–3 hours for audience building + upload.
Tips 7–9: Negatives + exclusions
Account-level negative keywords (request via Google support, not in PMax UI), brand exclusions (otherwise you cannibalise your brand Search campaign), URL exclusions for categories you don't want to push.
Negative keywords in PMax are a known frustration: they can't be added directly in the campaign UI. Account-level negatives (via Google Ads support) are the only route for general exclusion. Brand exclusions are available in PMax settings, set these before going live otherwise PMax eats your brand Search campaign. URL exclusions (e.g. thank-you pages, login pages) prevent PMax from sending traffic to irrelevant destination pages.
Expected impact: brand exclusions prevent up to 30% budget waste on branded queries coming through PMax. Time investment: 1–2 hours for exclusion setup.
Tips 10–12: Bidding + budget
Start with Maximize Conversions, then move to Target ROAS once you have 30+ conversions. Budget at least 30× your CPA (otherwise too little data for learning). Conversion tracking must be 100% correct, otherwise PMax draws wrong conclusions.
The 30× CPA rule is not a recommendation but a necessity: Google's algorithm needs 300–500 conversions per month for stable Target ROAS optimisation. Less data = unstable bidding, value optimisation on wrong signals. If your CPA is €50, you need at least €1,500 monthly budget for a learning PMax. Conversion tracking: install via both Google Tag Manager and enhanced conversions (hashed email matching). Import offline conversions (closed deals) for lead-gen to optimise PMax on deal value instead of lead volume.
Expected impact: switching from Maximize Conversions to Target ROAS after 30+ conversions typically gives 15–25% CPA reduction. Time investment: 1 hour for bidding strategy review every 4 weeks.
When NOT to use PMax
Accounts too small (<30 conversions/month), generic products with no differentiation (PMax pulls wrong traffic), unreliable conversion tracking. First optimise Search campaigns.
PMax is also not suited for brand awareness as a primary goal: the system optimises on conversions, not reach or frequency. For awareness, YouTube Ads or Display as a separate campaign works better. Seasonal products require manual CPM caps, otherwise PMax burns budget outside the conversion window. Finally: if competitor analysis shows competitors running PMax with high budget, your own PMax may cause cannibalisation on the same terms, consider a separate brand-protection campaign.
Tools we recommend
Google Ads Asset Library (free): central repository for all PMax assets, upload centrally and reuse across campaigns.
Google Ads Asset Report (free, in PMax UI): shows which headlines, images and videos score 'Best', 'Good' or 'Low'. Replace Low scorers monthly.
Google Tag Manager (free): implement enhanced conversions and offline conversion imports without code changes on the site.
Optmyzr (from $208/mo): PMax insights dashboard that shows search terms via workarounds, budget pacing and anomaly detection.
Triple Whale / Northbeam (for e-commerce): multi-touch attribution alongside Google's last-click model, gives a fairer picture of PMax contribution.
Google Analytics 4 (free): segment PMax traffic via campaign dimensions and view engagement quality alongside conversion data.
What changed in 2026
Google added 'Search themes' to PMax: you can now enter 25 search term themes to give the AI direction, the closest PMax has ever come to keyword targeting.
Asset group experiments are now available: A/B-test different asset group variants within one PMax campaign without creating separate campaigns.
PMax reporting has expanded with search category insights: instead of individual search terms you now see bundled categories, limited but better than nothing.
Brand exclusions can now be set independently via the campaign UI without a support ticket, a major improvement for advertisers wanting to prevent branded cannibalisation.
Want to optimise your Performance Max?
Request an Ads audit →