Performance Max Creative Assets: AI Generation Guide

The short answer

Performance Max assembles ads for every Google surface from the pieces in each asset group: headlines, long headlines, descriptions, images, logos, videos and your business name. The more complete and varied those pieces are, the more placements it can serve well. AI is useful for producing the text and adapting images at the volume Performance Max asks for. It is not a substitute for real product imagery, for your own video, or for someone checking every asset against what is true.

Step 1: plan asset groups around customer themes

An asset group should be a theme a buyer would recognise: a product category, a service line, or an audience with a distinct need. Google's best-practice guidance is to organise asset groups this way so the assets, the audience signal and the landing pages all match (Google Ads Help).

For an illustrative outdoor clothing retailer (hypothetical), three sensible asset groups would be waterproof jackets, walking boots and children's outdoor wear. Each gets its own headlines, images, audience signal and search themes. Mixing them in one group forces generic creative that fits none of them.

Step 2: know what each asset group needs

Limits and minimums change, so confirm them on Google's Performance Max specifications page and asset group guide when you build. At the time of writing, the figures below were consistent across Google's pages as reported:

Performance Max asset types, what to produce, and where AI helps

Asset type	Limit (confirm on Google Ads Help)	What to produce	AI role	Human check
Headlines	Up to 15, each up to 30 characters; at least 3	Two or three per angle: price, proof, range, use case, service, objection	Drafting by angle with character counts	Truth, standalone sense, no near-duplicates
Long headlines	Up to 5, each up to 90 characters	One complete proposition each, readable without any other asset	Drafting and tightening	Reads well over an image with no other text
Descriptions	Up to 5, each up to 90 characters; at least one of 60 characters or fewer	Detail the headlines cannot carry: what is included, who it suits, what happens next	Drafting, including a short version	Claims supported; short version still makes sense
Business name	Up to 25 characters	Your trading name as customers know it	None	Matches the website and account
Images	Several aspect ratios including landscape and square; up to 20 images	Real product and in-use photography, cropped to each ratio	Cropping, extending backgrounds, resizing	Product shown exactly as sold; no invented features
Logos	Square required; landscape optional; check current rules	Clean logo files on transparent or plain backgrounds	None	Correct version and colours
Videos	Up to 5; check minimum length and orientations	Short product or service videos in horizontal, vertical and square	Scripts, captions, cut-downs	Accuracy, sound-off readability, brand fit

Step 3: write text assets with AI, by angle

Give the model a brief per asset group: the theme, the landing page, the audience, a list of facts you can prove, and banned claims. Ask for text grouped by angle, with a character count on every line, then check counts in a spreadsheet, because models miscount.

Two rules make the difference between a full asset group and a useful one:

• • Each asset must stand alone. Performance Max may show any headline with any description and any image. "And free returns" is not a headline.
• • Variety of meaning, not wording. Five headlines that all say "quality jackets" count as one idea. Aim for five different reasons to buy.

The PPC manager's guide to AI ad creative has a full brief template and an angle matrix.

Step 4: images and video, where AI helps and where it does not

AI image tools are good at the tedious parts: extending a background to fit a square or portrait crop, removing clutter, producing seasonal backdrops for lifestyle shots. They are risky for the product itself. An image that shows a jacket in a colour you do not sell, or a feature it does not have, is misleading, and the Committee of Advertising Practice has said that disclosing AI use does not rescue a misleading image (ASA).

For video, supply your own even if it is simple: a 15 to 30 second product walk-through, captioned for viewing without sound, in horizontal and vertical versions. AI can write the script and captions and suggest cut-downs. Check the help page for how Google treats asset groups without video before deciding to leave it out.

Step 5: add the signals that steer the assets

Assets say what you offer; signals tell Performance Max who to start with:

• • Audience signals: customer lists and website visitors for that theme. They are starting points, not limits.
• • Search themes: phrases that describe what people search for in that theme.
• • Listing groups for retailers, so the product feed and asset group cover the same products.
• • Negatives and brand exclusions: Google's 2025 updates added campaign-level negative keywords to Performance Max (Google).

Step 6: refresh on evidence

After a few weeks of traffic, open the asset report for each group and the channel performance report for the campaign (Google Ads Help). Then:

1. • Replace assets the report rates poorly once they have had meaningful impressions, with a new angle rather than a reworded version.
2. • Keep a log of retired and winning angles per asset group.
3. • Check the channel split. If most spend goes to a surface where your buyers do not act, revisit video, images and signals for that surface.
4. • Refresh seasonal assets before the season, not after performance drops.

A monthly rhythm suits most accounts; high-spend retail accounts may need it more often around peak periods.

Common mistakes

• • One asset group for the whole catalogue.
• • Stock photos that look like every competitor's.
• • AI-altered product images that change what the product looks like.
• • Leaving brand searches inside Performance Max so it takes credit for people already looking for you.
• • Judging on platform ROAS alone; use the ROAS calculator with your margin.

FAQ

How many asset groups should a Performance Max campaign have?

As many as you have distinct themes with enough budget and conversions to learn. For a small account that may be two or three; splitting further spreads data too thin. A campaign can hold many asset groups, but more is not better by default.

Can I use entirely AI-generated images in Performance Max?

For abstract or lifestyle backgrounds it can work, but images of the product itself should show exactly what the customer will receive. Use AI to adapt real photography rather than to invent the product.

Why is my Performance Max Ad Strength low even with many assets?

Usually because assets repeat the same idea, a type is missing (often video or portrait images), or text does not relate to the theme. Adding distinct angles and missing formats typically raises it; judge performance on conversions either way.

Should I let Google generate assets from my website?

Treat automated asset creation as a draft source. Review what it creates where you can, and switch it off if you cannot control claims closely, for example in regulated sectors.