Google Ads Reveals Where PMax Ads Actually Run

What Google Ads API v23 Changes

The key update is channel-level performance reporting. In previous API versions, queries for Performance Max often returned a generic MIXED value, offering no insight into where ads were shown. With v23, the API returns specific channel data at the level of:

• campaign

• asset group

• individual assets

This makes it possible to clearly assess whether conversions are coming from Search, YouTube, Display, or other placements.

Why This Matters For E-commerce

For online retailers, this update has immediate, practical value. Performance Max has long been criticised as a “black box”. Channel-level reporting now allows businesses to:

• allocate budgets more accurately based on real channel performance

• optimise creatives with intent, understanding where video or product assets perform best

• measure ROAS more realistically across Google inventory

For European advertisers facing rising acquisition costs and tighter margins, this added transparency can directly influence profitability.

Combining Channels With Newer Segments

Channel reporting in v23 works alongside segmentation fields introduced in v22:

• ad_using_product_data – separates ads that use Merchant Center product feeds from those that do not

• ad_using_video – isolates impressions that included a video component

Together, these signals enable highly specific insights, such as comparing conversion value from video ads on YouTube versus Display, or analysing Shopping performance in Search against dynamic remarketing.

Important Limitations To Know

Google also outlines several constraints that advertisers and developers should note:

• Channel-level data is available only from 1 June 2025 onwards

• Asset group-level reporting is exclusive to the API and not available in the Google Ads interface

• Upgrading to v23 changes reporting behaviour, requiring updates to existing analytics and reporting systems

What This Signals

Performance Max is moving from a fully automated, opaque solution towards a model with greater control and clearer decision-making inputs. For e-commerce professionals and agencies, this is a strong signal to reassess PMax strategies – now backed by concrete channel-level data rather than aggregated results.