How to Report on Performance Max Campaigns

PMAX reporting challenges

Performance Max aggregates Search, Shopping, Display, YouTube, Gmail and Discover placements into a single campaign. Standard Google Ads reporting shows blended results. Without additional analysis, it is difficult to know whether PMAX is generating incremental conversions or simply capturing conversions that would have occurred through other campaigns (particularly brand search).

Key metrics to track

Track ROAS (revenue divided by ad spend) and CPA (cost per conversion) at campaign level. Track asset group performance for creative insights. Monitor impression share by channel (Search, Shopping, Display, YouTube) in the campaign overview. Compare PMAX conversion value against total Google Ads conversion value to understand share of wallet.

• Primary: ROAS and CPA trend over time (4-week rolling average)
• Secondary: impression share by channel and asset group performance rating
• Diagnostic: search query report for waste and feed quality signals

Measuring incrementality with Google Experiments

Use Google Ads Experiments to run a holdout test: split traffic 50/50 between PMAX and a control group (or a comparison campaign). The experiment reports incremental conversions — conversions that happened because of PMAX that would not have happened otherwise. Run the experiment for at least four weeks with sufficient conversion volume (50+ conversions in the experiment group) before reading results.

Key takeaways

• PMAX blends all channels. Track ROAS and CPA at campaign level, then drill into asset group performance.
• Compare PMAX to total Google Ads to understand contribution before scaling.
• Use Google Experiments holdout tests to measure true incrementality, not last-click attribution.

Frequently asked questions

What is a Performance Max campaign structure?

A Performance Max campaign uses a single campaign with multiple asset groups. Each asset group targets a product category or audience segment. The structure is simple but the asset quality is what drives results.

Where is TPR Media based?

TPR Media operates from Level 34, 1 Eagle Street, Brisbane City QLD 4000, serving clients across Brisbane and Australia-wide.

TPR Media explains Performance Max reporting for Australian businesses: the right KPIs (campaign-level ROAS and CPA, asset group ratings, channel impression share) and how to use Google Experiments holdout tests to measure PMAX incrementality beyond last-click attribution.