Google Ads Generative AI Video Resizing: What PMax Advertisers Need to Know (2026)

What is the new generative AI video resizing in Google Ads?

The key change is that Google Ads now uses generative AI to automatically create additional aspect ratio versions of existing Performance Max video ads. Announced in mid-August 2026, this asset optimization upgrade means advertisers no longer need to manually produce every video format — Google’s AI handles the resizing, cropping, and recomposition to fit placements like YouTube Shorts, in-stream ads, Discover, and Gmail.

Google Ads will use generative AI to resize Performance Max video ads, according to Search Engine Land. The feature is designed to help advertisers “maximize reach across more inventory” by filling in missing aspect ratios — typically vertical (9:16), square (1:1), and landscape (16:9) — from a single uploaded video.

This is not the first AI-powered creative tool Google has introduced, but it marks a significant step because it is fully generative rather than rule-based cropping. The AI analyzes the original video content and synthesizes new frames or rearranges existing material to produce coherent videos in the target dimensions.

How does generative AI video optimization work in Performance Max?

Performance Max (PMax) campaigns already used automation to place ads across Google’s entire inventory. The limitation was that advertisers had to supply videos in every required aspect ratio. If you uploaded only a landscape video, your ad would not run in vertical placements like YouTube Shorts.

With the new generative AI optimization, the system detects which aspect ratios are missing from your asset set. It then uses a generative model — not simple cropping — to produce those missing versions. According to Google Ads expands AI-generated aspect ratios for PMax video ads on Search Engine Watch, “Google Ads is expanding its asset optimization for Performance Max video ads by using generative AI to automatically create missing aspect ratios from existing video ads, which helps advertisers reach more inventory without additional production work.”

The process is largely automated. Once you upload your primary video, Google Ads generates the supplemental formats. Advertisers can then review, approve, or remove the AI-generated assets through the updated reporting dashboard.

What controls and reporting do advertisers have over AI video enhancements?

A frequent concern with generative AI in advertising is lack of control. Google has addressed this with a dedicated help article on advanced reporting and controls for creative video automation in Performance Max. The documentation outlines several key capabilities:

• Performance monitoring: Advertisers can see how AI-enhanced videos perform compared to original assets, including metrics like view-through rate and conversion lift.
• Asset removal: Individual AI-generated videos can be removed if they do not meet brand standards.
• Feature toggles: Advertisers can proactively turn off specific types of creative automation — for example, disabling generative resizing while keeping text overlays enabled.
• Transparency labeling: AI-generated assets are clearly marked in the reporting interface so advertisers always know which creative is original and which is AI-produced.

This level of control is important for brands with strict visual guidelines. Google is positioning the feature as an optional efficiency tool, not a forced automation.

Comparison: Manual vs. AI-generated video aspect ratios

Aspect	Manual Production	AI-Generated Optimization (New)
Time to produce a vertical version	Hours to days (editing, rendering)	Minutes (automated generation)
Cost per format	High (editor time, software, revisions)	Included in existing PMax campaigns
Brand control	Full (every pixel is deliberate)	Moderate (review and remove options)
Consistency across formats	Strong (same assets, same edit)	Variable (AI may recompose elements)
Reach across inventory	Limited by formats uploaded	Full (all formats automatically covered)
Reporting transparency	Simple (you know what you uploaded)	Enhanced (AI assets labeled and tracked)

What other AI Max tools did Google launch alongside this update?

Around the same timeframe, Google also rolled out broader AI Max testing and planning tools for Search campaigns. Google adds new AI Max testing and planning tools reported on August 20, 2026, that these include multi-campaign A/B testing and enhanced Performance Planner functionalities. The new tools allow advertisers to assess the impact of budget changes and ROI target adjustments before implementing them.

In addition, a separate article on Search Engine Journal covers Google Ads Launches New Search and AI Max Experimentation Tools. These experimentation capabilities complement the video resizing feature by giving advertisers more structured ways to test AI-driven campaign optimizations before scaling them.

Why this matters for advertisers

For advertisers, the implications are twofold. First, the generative AI video resizing removes a significant production bottleneck. Small and medium businesses that lack resources to produce multiple video formats can now run campaigns across all Google inventory without specialized video editing skills.

Second, the introduction of reporting and controls signals that Google is listening to advertiser concerns about AI creative automation. Last year, broader news surfaced about AI-generated ads on platforms like Shopee and TikTok that misled customers — as reported by Channel News Asia: Sellers on Shopee, TikTok call out auto-generated AI ads that mislead customers. Google’s transparency features aim to prevent similar brand safety issues by keeping human oversight in the loop.

How should advertisers prepare for generative AI video optimization?

If you run Performance Max campaigns, here are practical steps to take advantage of the new feature:

1. Audit your existing video assets. Identify which aspect ratios you currently supply and which are missing. The AI can only work with what you provide, so a high-quality source video in 16:9 will yield better generated vertical versions.

2. Review the new reporting controls. Log into Google Ads and explore the “Creative video automation” section. Familiarize yourself with the performance metrics and removal options before the AI-generated assets go live.

3. Test on a single campaign. Before enabling generative resizing across all campaigns, test it on a low-risk campaign. Monitor performance metrics and user feedback for any unexpected behavior.

4. Set brand guidelines for AI output. Create a checklist of what is acceptable and what needs human review — for example, ensuring that AI-generated videos do not crop out faces or key product shots.

5. Combine with experimentation tools. Use the new AI Max A/B testing features to run controlled experiments comparing campaigns with and without generative video resizing. This data will help justify scaling the feature.

Potential risks and limitations

While the generative AI video resizing is powerful, it is not perfect. Because the AI recomposes video content, there is a risk that key visual elements — text overlays, product logos, or specific framing — could be altered in ways that dilute brand messaging.

Additionally, the generative process adds latency. Google notes that AI-generated assets may take “up to a few hours” to appear in the campaign after upload, which could delay campaign launches for time-sensitive promotions.

Another consideration is cost. While the feature itself does not carry an extra fee, Performance Max campaigns may see increased delivery across more inventory, which could raise overall ad spend. Advertisers should set appropriate budget caps and monitor spend closely during the initial rollout.

Practical examples of AI prompts for Google Ads

Practical eCommerce published a useful resource on 3 AI Prompts for Google Ads that applies to the video optimization context. When using generative AI for ad creative, specificity matters. For example, a prompt like “Create a 9:16 version that keeps the product shot centered and the call-to-action visible” will produce better results than vague instructions.

The bigger picture: AI-generated ads across platforms

The Google Ads generative AI video resizing is part of a broader industry trend. Platforms like TikTok have faced controversy over AI-generated ads that mislead customers — as highlighted in the Channel News Asia report. The candy brand featured in A candy brand discovered TikTok made an AI clone of its founder to run ads is a cautionary example of what happens when creative control is ceded entirely to AI.

Google appears to have learned from these incidents by building guardrails into the process. The reporting dashboard and asset removal capabilities give advertisers a backstop against unwanted AI-generated content.

Conclusion

Google Ads’ generative AI video resizing is a meaningful upgrade for Performance Max advertisers who want to maximize reach without multiplying production costs. The feature eliminates a major friction point — the need to produce every video format manually — while the accompanying reporting and control tools address legitimate concerns about brand safety and transparency.

For advertisers willing to test and monitor, this is a low-risk way to extend campaign reach into YouTube Shorts and other growing placements. As with any AI-driven automation, the key is to maintain human oversight and use the available controls to enforce brand standards.