Performance Max campaigns

The honest take on Performance Max

We recommend PMax for e-commerce with product feeds. Avoid it for lead gen until you have 50+ conversions per month and solid offline conversion tracking. If you don't have enough conversion data, PMax will optimize for junk — form spam, low-quality leads, and bot traffic that looks like conversions to the algorithm.

Google reports that PMax delivers 18% more conversions at a similar CPA compared to standard campaigns. That stat is real, but it comes with a massive asterisk: it's averaged across accounts with mature conversion tracking and sufficient budget. For accounts without those prerequisites, PMax regularly underperforms a well-structured Search campaign.

The black box problem

You can't see which search terms triggered your ads. You can't control placements. You're trusting Google's algorithm entirely. That's the deal with PMax, and you need to go in with eyes open.

Google shows you "search categories" instead of actual search terms — so you know your ads matched "running shoes" queries, but not whether someone searched "running shoes near me" or "running shoes ugly." On Display and YouTube, you get even less. Your ads could be running on low-quality mobile apps or irrelevant YouTube channels and you'd never know.

For accounts spending $10K+/month, this lack of visibility is a real risk. You can partially mitigate it with account-level placement exclusions and brand exclusions, but you'll never have the same control as standard Search or Shopping campaigns.

PMax vs. standard Search campaigns

Always add brand exclusions

This is non-negotiable. Without brand exclusions, PMax will cannibalize your cheap brand traffic and take credit for conversions that would have happened anyway. Someone searches your brand name, PMax shows the ad, they convert — and PMax reports it as a win. In reality, that person was already coming to you.

Add brand exclusions in your PMax campaign settings under "Brand exclusions." Exclude your own brand and common misspellings. This forces PMax to earn its conversions from non-brand traffic, which gives you an honest picture of whether it's actually driving incremental value.

Asset groups: how to set them up right

Each PMax campaign uses asset groups — bundles of headlines, descriptions, images, and videos that Google mixes and matches. The number one mistake is dumping everything into a single asset group. Instead, create separate asset groups for distinct product categories or audience segments.

Per asset group, provide at least 5 headlines, 5 descriptions, 5 images (1200x628 landscape and 960x960 square), and a video. If you don't provide a video, Google will auto-generate one from your images — and it will look terrible. Upload even a basic 15-second video to avoid that.

Audience signals matter more than most advertisers realize. Add your customer lists, website visitors, and custom segments based on search themes. These aren't hard targeting — they're hints that tell Google where to start looking. Without good audience signals, the algorithm starts cold and wastes budget figuring out who to target.

How Fullrun handles Performance Max

Fullrun doesn't default to PMax for every account. It evaluates your conversion volume, tracking maturity, and business type first. For e-commerce accounts with product feeds and 50+ monthly conversions, Fullrun typically recommends adding PMax alongside existing Shopping and Search campaigns. For lead gen accounts, Fullrun builds a strong Search foundation first and layers PMax in only when there's enough conversion data for the algorithm to optimize against real outcomes, not just form fills.