Google Ads adds A/B tests for budgets and CPA or ROAS targets

Google Ads has started showing advertisers a beta experiment that compares different budgets and campaign targets. Search Engine Roundtable described the option on 10 September 2026.

The option covers Search campaigns only

In the experiments area the new entry is called “Budget or bidding targets for Search campaigns”. Google describes it as a way to test different budget, target CPA or target ROAS amounts. Target CPA is the price an advertiser is willing to pay for one sale or one enquiry. Target ROAS is how much revenue the advertiser wants back from each amount spent. The option does not cover Shopping, Display or video campaigns.

Performance Planner applies a target change in one click

Google connected the same workflow to Performance Planner. The tool now shows how a change to a bidding or budget target may affect campaigns that are already running. The suggested change can be pushed straight into the account, and single campaigns can be deselected first. Everything lands in Bulk Actions, so it can be undone. That sits alongside the AI dashboards that reached advertiser accounts this week.

AI Max tests keep brand and location settings switched on

AI Max is Google’s automated version of a Search campaign. Until now an advertiser had to switch off brand and location controls to run an AI Max test. Google said those settings can stay on. A second change lets one A/B test cover several Search campaigns at once instead of one. Google said that version starts rolling out in September 2026.

A small account may not gather enough data for a split test

A test splits the traffic, so each half collects fewer clicks and fewer sales. On a campaign with a handful of sales a week, the gap between the two halves stays inside the margin of error for months. The multi-campaign version helps, because it pools several campaigns into one test. Advertisers should also count the cost of the control group, which keeps spending at the old level for the whole test. Microsoft went the other way when it dropped the Max CPC cap from new automated campaigns, and Google keeps pulling shop sales into Data Manager. Before starting a test, set the question, the length and the minimum number of sales that will settle it.