How much budget does Performance Max need?
Performance Max needs enough budget to produce a steady flow of conversions, which in practice means planning for roughly one conversion a day per campaign rather than picking a round number. If your cost per conversion is $60, a $20 daily budget will never give the model enough to learn from.
Start with the math. Take your recent cost per conversion from Search or Shopping, multiply it by 30 to 50 conversions a month, and that is the monthly spend one PMax campaign should be able to absorb. Google's budget panel at setup also shows low, medium and high daily recommendations based on your account history. Treat the low one as a floor, not a target.
If the math doesn't work, run fewer campaigns, not smaller ones. One well-fed campaign beats three starved ones splitting the same money. Our own minimum is $3,000 a month in ad spend, and below that we usually point people to tightly built Search campaigns first.
Sources: About Performance Max campaigns (budget panel) - Google Ads Help
How do I test whether Performance Max is actually incremental?
Turn it off somewhere on purpose and measure what you lose. Reported PMax ROAS tells you what it took credit for, not what it caused, so the only honest test is a holdout.
We run that a few ways. A geo holdout excludes a set of zip codes or a region for three to four weeks and compares total sales there against similar areas where PMax kept running. You can also flip it and run PMax only in that area. A timing test pauses PMax during certain hours or days. A split test runs a branded PMax campaign and a non-brand one side by side, so you can see how much of the result is just your own name.
Judge every test on total business results: orders in your store, closed deals in the CRM, not the conversions column in Google Ads. If revenue barely moves when PMax goes dark, it was mostly collecting demand you already had. If the tracking itself is shaky, fix that first with a conversion tracking audit, or the test will measure noise.
Sources: Experiments FAQs - Google Ads Help
Should I use Performance Max or Search campaigns?
Most accounts should run both, with Search covering the queries you want full control over and Performance Max handling reach across the rest of Google. It is a strategy choice, not a question of which campaign type is better.
Search gives you keyword-level control, ad copy written for each intent and clean reporting. That makes it the right home for brand terms, your highest-intent non-brand keywords and anything where the message has to be exact. PMax works best when you have complete conversion tracking, real monthly volume and strong creative, and you're comfortable letting automation pick the channel.
The two also interact. Google says a Search campaign with an exact match keyword is prioritized over PMax when the query matches that keyword, while PMax search themes carry the same priority as phrase and broad match. So exact match on your core terms is how you keep those queries in Search. More on the split in our paid search service and the PMax guide.
Sources: About Performance Max campaigns (Search integration and campaign controls) - Google Ads Help
Can I see where my Performance Max ads are showing?
Yes, far more than you could a couple of years ago. The channel performance report under Insights and reports breaks results down across Search, Shopping, YouTube, Display, Discover, Gmail and Maps, and search terms insights show which queries triggered your ads.
Keep in mind that channel reporting is visibility, not a dial. You still can't tell PMax to put 80% of the budget on Search. What you can do is act on what you see. Pull the placement data and exclude apps and sites sending junk traffic. If you already run Display remarketing with the same images, reuse those placement exclusions and audience lists in PMax. In search terms insights, the source column shows whether a query came from your search themes or from PMax finding it on its own.
A check you can do today: open the channel report, sort by cost, and ask whether the channel taking the most money is the one you would have picked. If it's Display and your conversions mostly come from Search, that's where we'd start digging.
Sources: Answering Your Top Questions About Performance Max - Google Ads Help, Kick off 2025 with new Performance Max features - Google
What is the difference between Performance Max and AI Max for Search?
AI Max is a setting you turn on inside an existing Search campaign, while Performance Max is its own campaign type that serves across every Google channel. AI Max stays on Search. PMax goes everywhere.
AI Max ties Smart Bidding, responsive search ads and landing page selection from your site into one loop, and lets Google match queries beyond your keyword list. You keep the Search campaign structure, the search terms report and full negative keyword control. PMax gives up keyword structure entirely and decides the channel mix for you.
We treat them as different jobs. AI Max is a way to stretch a healthy non-brand Search campaign into queries you haven't thought of. PMax is for cross-channel reach, and for retailers it's the main home of Shopping inventory. Neither fixes bad inputs. If your conversion goals count junk, both will find more junk, faster. Test AI Max on one campaign with a clear before and after, the same way you'd test a bid strategy change.
Sources: About Performance Max campaigns - Google Ads Help
Should I manage Performance Max myself or hire an agency?
You can manage Performance Max yourself if you have clean conversion tracking, a healthy feed and time to read its reports every week. Bring in help when the spend is meaningful and you can't explain what it's doing with it.
Setup is the easy part. The work is in the ongoing checks: brand traffic leaking in, final URL expansion sending visitors to blog or careers pages, asset groups starving, auto-generated video showing up, and conversion values drifting away from margin. Each takes a few minutes to spot if you know where to look, and a few months to notice if you don't.
A fair test: if you can say how much of last month's PMax revenue came from brand searches and returning customers, you're probably fine on your own. If you can't, start with a free Google Ads audit, with results back within 48 hours. When we manage PMax, it sits inside our Google Ads management retainer, a flat monthly fee plus a small percentage of spend, and John approves every change.
