UGC for Facebook and TikTok Ads: Best Practices and Winning Formats

UGC videos generate, on average, 4 times more engagement than traditional branded content on social platforms. On Facebook Ads and TikTok Ads, the UGC (User Generated Content) format leads the pack because it mimics each platform's native language: authentic, direct, and shot like organic content. Thanks to the rise of AI UGC tools, marketing teams can now produce these videos at scale without the need for shooting or casting.

What is AI UGC and why it's revolutionizing social ads

AI UGC refers to videos in a "user-generated content" style created by artificial intelligence, featuring realistic avatars instead of human actors. For a definition and benefits of AI UGC in digital marketing, the concept is simple: you write a script, choose an avatar, and the platform generates a ready-to-publish video.

Why are media buyers so interested? Here are three compelling reasons:

• Speed: an AI UGC video can be produced in a matter of minutes, compared to several days for a traditional shoot
• Cost: no creator briefings, no studio, no heavy post-production
• Volume: you can create 50 variations of the same message for A/B testing in just one day

The most prominent tools on the market each offer their unique approach. Hoox specifically targets ad performance: customizable avatars by audience, videos with integrated CTAs, and formats optimized for every ad placement.

Top-performing UGC formats on Facebook ads

Facebook still boasts the largest ad inventory. But not all UGC formats are created equal. Here are the combinations that yield the best results.

Square format (1:1) for the news feed

The 1:1 format takes up more space in the mobile feed than the traditional 16:9. On Facebook, it's the ratio that maximizes visibility without being cut off by the interface. For optimal UGC social ads performance, structure your creative like this:

• Visual hook in the first 3 seconds: a face talking to the camera, a direct question, or a movement that grabs attention
• Ideal length between 15 and 30 seconds: long enough to make a point, short enough to keep viewers watching
• Mandatory subtitles: 85% of Facebook videos are watched without sound
• Clear CTA at the end of the video: "Try for free," "Discover the offer," no vague wording

Vertical format (9:16) for reels and stories

Since Meta started pushing Reels, the vertical format has become essential on Facebook too. Best practices for this placement include:

• Film or generate in native 9:16, never crop a horizontal video
• Keep text and key elements in the central safe zone, avoiding the top and bottom 15% hidden by the interface
• Use a conversational tone: overly promotional content is penalized by the algorithm on Reels

The hook-problem-solution: the structure that converts

Most high-performing AI UGC ads on Facebook follow this structure:

1. Hook (0-3s): "Are you paying too much for leads on Meta?"
2. Problem (3-10s): "Your creatives burn out in 5 days and your CPA skyrockets"
3. Solution (10-20s): product presentation with social proof or demo
4. CTA (20-25s): specific action to take

UGC TikTok ad formats: what really works

TikTok is a completely different environment from Facebook. Content that performs looks like what users post themselves. Any video that seems too promotional is instantly ignored.

Always native vertical

On TikTok, 9:16 isn't an option, it's the only viable format. Winning formats share these traits:

• Smartphone quality: a video that's too polished performs worse than content that looks handheld
• Duration of 15 to 45 seconds: TikTok rewards videos watched in full. Better 20 seconds viewed at 100% than 60 seconds viewed at 30%
• Text on screen from the first frame: TikTok users visually scan before listening
• Music or sound design: unlike Facebook, sound is on by default on TikTok

The 3 UGC TikTok formats that drive ROAS

The face-to-camera testimonial: an avatar or creator sharing their product experience. Direct, personal, no staging. It's the easiest format to produce with an AI UGC video generator and often the most effective.

The "get ready with me" or routine: the product is integrated into a daily routine. Works particularly well for e-commerce, especially in skincare, fashion, or food.

The unboxing or first use: showing the product in a real-life setting. This format sparks curiosity and reduces purchase friction.

How to create AI UGC ads optimized for each platform

Creating high-performing AI UGC videos isn't just about generating a talking avatar. Here's the complete process to produce creatives that convert.

Step 1: adapt the script to the platform

The same message doesn't work the same way on Facebook and TikTok. On Facebook, you can be more explicit about product benefits. On TikTok, the tone should remain native and conversational. Write two versions of each script.

Step 2: choose the right avatar for the audience

The avatar should match the target persona. An AI UGC creator aimed at selling SaaS software won't have the same profile as an avatar for a cosmetics brand. Hoox allows avatar customization by audience: age, style, tone of voice, language. It's a performance lever often underestimated, especially for SaaS.

Step 3: produce variations and test

The strength of AI UGC marketing lies in the ability to iterate quickly. You can generate dozens of variations by changing the hook, CTA, or avatar. Each variation becomes a creative test in your campaign. Teams testing more than 10 creatives per week reduce their CPA by 20 to 40% on average compared to those running with 2 or 3 visuals.

For a deeper dive into the results, check this comparison of AI UGC and traditional UGC performance in ads.

AI UGC vs. Human UGC: Do you have to choose?

AI doesn't replace UGC creators. It solves a different problem: volume and speed of production. A human creator brings authenticity and spontaneity that's hard to replicate. But when you need 30 creative variations to test 6 audiences on 2 platforms, the human model struggles to scale.

The winning strategy combines both. Use human creators for your hero concepts, the flagship videos of your campaign. Then use an AI UGC video generator to spin off these concepts into dozens of variations, test new angles, and keep your campaigns continuously fueled.

To keep up with the evolution of UGC ad formats, this synergy between human and AI is becoming the standard among the most advanced advertisers.

FAQ

How to make AI UGC ads for Facebook and TikTok?

You write a script tailored to each platform, choose an avatar that matches your target audience, and generate the video with a tool like Hoox. For Facebook, opt for square (1:1) or vertical (9:16 for Reels) formats. For TikTok, 9:16 is a must. Add subtitles, a punchy hook in the first 3 seconds, and a clear CTA.

What are the best AI tools for generating user-generated content?

The most popular tools for creating AI UGC videos are HeyGen, Creatify, and Hoox. The choice depends on your goal: if you're looking for a conversion-focused tool, go for a solution with platform-optimized formats and integrated CTAs.

Is AI UGC legal?

Yes, AI UGC is legal as long as you adhere to certain conditions. You must not use the face or voice of a real person without their consent. AI-generated avatars are synthetic characters, which eliminates this risk. Some jurisdictions require you to disclose that the content is AI-generated, especially in the European Union with the AI Act. Check local regulations for your target markets.

What are the benefits of using AI for managing user-generated content at scale?

The main advantage is the ability to produce a high volume of creatives without proportionally increasing costs. A marketing team can create 50 variations of AI UGC videos in one day, compared to 2 or 3 with a traditional shooting process. This allows testing more creative angles, refreshing campaigns before ad fatigue sets in, and tailoring messages to each audience segment. For brands heavily investing in social ads, it's a direct lever for reducing CPA.

Sources

• Comparison of AI UGC and traditional UGC performance in ads
• Definition and benefits of AI UGC in digital marketing
• Evolution of UGC ad formats