Google Ads Rolls Out New Testing and Planning Tools for AI Max

Google Ads has announced three new tools for AI Max: Multi-Campaign Budget Testing (rolling out in September 2026), Enhanced Experiment Controls, and an improved Performance Planner that now forecasts how budget and bidding changes could affect a campaign and lets advertisers apply them in one click.

Brandon Ervin, Director of Product Management for Search Ads at Google, announced the update on August 20, 2026, in a post titled “Make AI Max work for your business with new testing and planning tools” on the official Google Ads blog. Google Ads also shared the same announcement in an official LinkedIn post, inviting advertisers to try the new tools ahead of the Rethink 2026 event.

What’s changing

AI Max for Search is the campaign format where Google automatically expands keywords, ad copy, and landing pages using AI. Advertisers’ most common concern with AI-driven formats like this is always the same: it’s hard to isolate the real business impact of turning on AI logic, and it’s hard to test it safely without losing control over brand and budget. These three new tools address exactly that:

• Multi-Campaign Budget Testing — A/B test different budgets and ROI targets across several Search campaigns within a single experiment.
• Enhanced Experiment Controls — expanded A/B test settings that keep brand and location guardrails in place while measuring AI Max impact.
• Improved Performance Planner — the planner now shows the forecasted impact of budget and bidding changes on a specific existing campaign, and lets you apply the suggested changes in one click.

Multi-Campaign Budget Testing

In September 2026, Google Ads is rolling out an A/B test that lets advertisers test different budgets and ROI targets across several Search campaigns at once, inside a single experiment — to understand how scaling budget actually affects business results, not just individual campaign metrics. The tool builds on the one-click experiments for AI Max Google introduced earlier — now advertisers can scale that same testing approach across a whole portfolio of campaigns instead of checking each one individually.

For agencies and advertisers running dozens of Search campaigns at once, this means considerably less manual work: instead of testing a budget change on each campaign sequentially and waiting weeks for statistical significance each time, teams can launch a single portfolio-level test and get an aggregate read on ROI impact.

Enhanced Experiment Controls

The second tool, Enhanced Experiment Controls, addresses what advertisers most often name as the main barrier to testing AI-driven formats: the fear of losing control over brand and location targeting in exchange for AI automation. According to Google Ads’ official help article on A/B experiments, the new expanded controls let advertisers keep a campaign’s brand and location guardrails unchanged even in the test arm of an AI Max experiment. That makes it possible to isolate the effect of AI logic alone, without sacrificing constraints already agreed with brand or legal teams.

Improved Performance Planner

The third tool isn’t about A/B testing — it’s about forecasting. According to Google Ads’ help article on Performance Planner, the tool now shows how specific changes — such as adjusting bids or increasing budget — could affect an existing, active campaign, rather than only a hypothetical plan. After seeing the forecast, advertisers can apply the suggested changes directly to the campaign in one click, without switching to a separate budget or bid editing interface.

In practice, this closes the gap between “planning on paper” and actually implementing changes in the account — previously, advertisers had to manually transfer Performance Planner’s conclusions into campaign settings themselves.

Key dates

• August 20, 2026 — Google officially announced all three tools on the Google Ads blog and on LinkedIn.
• September 2026 — Multi-Campaign Budget Testing becomes available to advertisers.
• September 16–17, 2026 — Rethink 2026, a virtual event where Google will go deeper into scaling performance with AI, including these new testing and planning tools.

Who this affects

The update primarily affects advertisers and agencies already using AI Max for Search or considering the switch. Accounts running a large number of Search campaigns will see the most practical benefit: that’s exactly where manually testing budgets campaign by campaign used to eat up the most time, and it can now be replaced with a single portfolio-level A/B test. Smaller accounts with just one or two active Search campaigns benefit too — mainly through the improved Performance Planner, which works regardless of account scale.

Spilno Agency’s take

What matters most here isn’t that AI Max got bigger — it’s that Google is finally giving advertisers a way to test AI logic in a controlled, measurable way instead of “turn it on and see what happens.” Brand and location guardrails are exactly what many clients were missing before delaying their move to AI Max out of fear of losing control over their ads. That said, one thing to keep in mind: a portfolio-level A/B test across several campaigns at once shows the aggregate effect, but it doesn’t always reveal that one specific campaign in the portfolio underperformed relative to the others — so results are still worth checking at the individual campaign level, not just the aggregated experiment report. If you need help setting up a safe AI Max test for your account, the Spilno Agency team is ready to help.

If you’re still getting familiar with Performance Max, where AI logic also plays a central role, our Performance Max guide for beginners walks through the core setup principles. And if you’d like to check how ready your account is for testing these new AI tools, request a free Google Ads audit.

Frequently Asked Questions (FAQ)

What is Multi-Campaign Budget Testing in Google Ads?

It’s a new A/B test that lets advertisers check different budgets and ROI targets across several Search campaigns at once, within a single experiment. The tool becomes available in September 2026 and builds on the existing one-click experiments for AI Max.

What are Enhanced Experiment Controls?

These are expanded A/B test settings in Google Ads that let advertisers keep a campaign’s brand and location guardrails unchanged while testing AI Max impact. Previously, advertisers couldn’t always isolate the effect of AI automation without risking those constraints.

What changed in Performance Planner?

Performance Planner now shows the forecasted impact of specific changes — such as adjusting bids or budget — on an already active campaign, rather than only on a hypothetical plan. Suggested changes can be applied instantly, in one click, without switching to a separate interface.

When will these tools become available?

The announcement came on August 20, 2026. Google plans to roll out Multi-Campaign Budget Testing in September 2026. The exact availability for a specific account should be checked directly in the Google Ads interface, since features roll out gradually.

What is Rethink 2026 and when does it take place?

Rethink 2026 is a virtual Google event focused on scaling advertising performance with AI, including the new AI Max testing and planning tools. The event takes place September 16–17, 2026, with registration open on Google’s official page.

Do I need to manually turn on the new testing tools?

Google hasn’t detailed a separate toggle for enabling these tools — they appear inside the standard Experiments and Performance Planner interfaces as the update rolls out to each account. If the features haven’t shown up in your account by September 2026, check back later, since the rollout is gradual.

Does this update apply only to AI Max for Search, or to Performance Max too?

The announced tools are primarily aimed at AI Max for Search. Google Ads didn’t officially extend these three specific tools to Performance Max in this announcement — but the improved Performance Planner appears to work at the account and campaign level more broadly, so it’s worth checking its availability for other campaign types directly in the interface.