Do AI-generated TikTok captions actually convert? We tested 300 posts.
We ran 300 posts across six affiliate niches: 150 with human-written captions, 150 generated by an AI trained on our hook library. Here is what happened.
The setup
Same videos, same offers, same posting times. Only the caption text changed.
The numbers
- Average retention: AI +6.2%.
- Comments per view: human +11% (people replied to the writer's voice).
- Click-to-buy rate: AI +18% — the model was better at closing loops.
- Overall sales per 1,000 views: AI +14%.
Why AI won
Three reasons:
1. Consistent hook + payoff structure. Every caption had a promise in line one and a payoff by line three.
2. First-person voice locked in. Once we fed the model 10 samples, it stopped sounding like a bot.
3. No wasted characters. No emojis for decoration, no throat-clearing.
Why humans still matter
Captions with personal detail — "my mom said" or "I bought this the day I quit" — outperformed both baselines. AI can't invent your life.
The template that won
1. Hook — open a loop or name the viewer.
2. Specific claim — a number, a timeframe, a comparison.
3. CTA — softer than "buy now". Try "storefront in bio" or "tap the yellow tag".
What to do with this
Use AI to draft, then spend 15 seconds adding one personal detail. That combination beat both extremes in every niche we tested.
AffiliateFlows AI ships this exact caption engine, trained on your best-performing posts. Join the waitlist to try it in early access.