ChatGPT vs Claude vs Gemini for Email Marketing — Real A/B Test Results
ChatGPT vs Claude vs Gemini: I Tested All Three for Email Marketing — Claude Won
Lisa ran the same campaign through ChatGPT, Claude, and Gemini. Same list, same product, same everything. Claude AI destroyed the competition. Here’s exactly what happened.
Her email list was dying. 12,000 subscribers, 8% open rate, 0.3% clicking through. Industry average is 21% opens. She was below bottom quartile. Something had to change.
So Lisa did what any rational person would do—ran a three-way AI death match. ChatGPT software vs Claude AI vs Gemini chatbot. 4,000 subscribers each, identical offer, let the best AI win.
The results hurt some feelings.
The Test That Nobody Else Would Run
The Setup:
- Product: $497 course on Amazon FBA
- List segment: 12,000 “warm” subscribers
- Split: 4,000 per AI
- Subject lines: Each AI wrote their own
- Body copy: Each AI’s style
- Send time: Tuesday 10 AM EST
- Tracking: Opens, clicks, sales
Lisa gave each AI the same brief: “Sell this course. Make them buy. Don’t sound like spam.”
What came back revealed everything about how these AIs think.
ChatGPT’s Emotional Manipulation
ChatGPT wrote like a friend who really wants you to succeed:
Subject: “I found your biggest Amazon mistake (fix takes 5 min)”
Opening: “Hey Sarah, Quick story: Remember when I couldn’t sell a single unit on Amazon? Last month I cleared $47K. The difference was fixing one stupid mistake…”
ChatGPT created an emotional journey. Hope, fear, excitement, urgency. Every psychological trigger in sequence.
Results:
- Opens: 34% (1,360 people)
- Clicks: 8.2% (328 people)
- Sales: 2.3% (92 people)
- Revenue: $45,724
Not bad. But watch what Claude did.
Claude’s Logical Devastation
Claude wrote like a consultant with your P&L statement:
Subject: “Your Amazon ROI is 73% below potential”
Opening: “Based on average seller data, you’re losing $3,400 monthly. Here’s the math: [detailed breakdown]. This course fixes three specific problems…”
No emotion. Pure logic. Claude listed facts, showed calculations, proved ROI.
Results:
- Opens: 41% (1,640 people)
- Clicks: 11.3% (452 people)
- Sales: 3.8% (152 people)
- Revenue: $75,544
Claude crushed it. But why?
Gemini’s Speed Run Attempt
Gemini wrote like someone with ADHD who drank too much coffee:
Subject: “Amazon course inside! Limited time! Act now!”
Opening: “This course teaches Amazon! You’ll learn FBA! Make money fast! Proven system! Thousands succeeded!”
Gemini prioritized speed over everything. Short sentences. Many variations. Throw everything at the wall.
Results:
- Opens: 29% (1,160 people)
- Clicks: 6.7% (268 people)
- Sales: 1.9% (76 people)
- Revenue: $37,772
Gemini lost. Speed without strategy is just noise.
Why Claude Dominated
Lisa analyzed every email. Claude won because it understood something the others missed: People buy with logic and justify with emotion, not the reverse.
ChatGPT appealed to feelings first. Gemini appealed to urgency. Claude appealed to the wallet.
Claude’s email contained:
- 7 specific data points
- 3 competitor comparisons
- ROI calculation
- Risk reversal (money-back guarantee framed as “mathematical impossibility of loss”)
- Social proof with exact numbers
More details here about the psychological framework, but the summary is simple: Claude treats readers like adults with calculators.
The Combination That Beat Everything
After seeing results, Lisa tried something crazy: Use all three AIs together.
The Trinity Formula:
- ChatGPT writes subject line (emotional hook)
- Claude writes body copy (logical argument)
- Gemini creates 20 variations for testing
This hybrid approach delivered:
- Opens: 52% (2,080 people)
- Clicks: 14.7% (588 people)
- Sales: 4.7% (188 people)
- Revenue: $93,436
The combination beat each AI individually by 23%.
Subject Line Breakdown
ChatGPT’s winners:
- “I found your biggest Amazon mistake (fix takes 5 min)”
- “This Amazon seller made $47K last month (started with $500)”
- “Warning: Your competitors know this Amazon secret”
Claude’s winners:
- “Your Amazon ROI is 73% below potential”
- “Mathematical proof: This course pays for itself in 11 days”
- “Data from 10,000 sellers reveals optimal strategy”
Gemini’s attempts:
- “Amazon course inside! Limited time! Act now!”
- “Make money with Amazon FBA today!”
- “Proven system thousands succeeded!”
ChatGPT’s subject lines got opened. Claude’s emails got sales. Gemini got deleted.
The Templates That Convert
ChatGPT Template (Emotional):
Subject: [Curiosity gap + personal element]
Hey [Name],
[Personal story that mirrors their situation]
[Moment of discovery]
[Transformation achieved]
[How they can get same result]
[Urgent reason to act now]
[Soft CTA with emotion]
Claude Template (Logical):
Subject: [Specific metric + gap analysis]
[Name],
[Data-driven problem statement]
[Mathematical breakdown of loss]
[Solution with proven ROI]
[Competitor comparison]
[Risk reversal with numbers]
[Direct CTA with guarantee]
When to Use Each AI
Use ChatGPT when:
- Selling to consumers
- Product is emotional purchase
- Building relationship first
- Story-driven brands
Use Claude when:
- Selling to businesses
- Product is logical purchase
- ROI matters most
- Data-driven buyers
Use Gemini when:
- Need 50 variations fast
- Testing what works
- Quantity over quality initially
- Brainstorming angles
The Psychology Behind Performance
ChatGPT understands human emotion because it trained on human writing. It knows what makes people feel.
Claude understands human logic because it trained on academic papers and analysis. It knows what makes people think.
Gemini understands speed because it’s optimized for rapid generation. It knows how to produce, not persuade.
Your email strategy should use all three. Let them fight in A/B tests. The winner takes your wallet.
<blockquote class=”twitter-tweet”><p lang=”en” dir=”ltr”>Steal this chatgpt cheatsheet for free😍<br><br>It’s time to grow with FREE stuff! <a href=”https://t.co/GfcRNryF7u”>pic.twitter.com/GfcRNryF7u</a></p>— Mohini Goyal (@Mohiniuni) <a href=”https://twitter.com/Mohiniuni/status/1960655371275788726?ref_src=twsrc%5Etfw”>August 27, 2025</a></blockquote> <script async src=”https://platform.twitter.com/widgets.js” charset=”utf-8″></script>
The Money Is in the Testing
Lisa now runs every campaign through all three AIs. Tests everything. The winner gets scaled.
Last month: $340K in course sales from email alone. Cost: $20 in API credits.
The lesson? Stop picking an AI based on feelings. Test them based on results.
Claude won this round. Next month might be different. The only way to know is to test everything, measure everything, scale what works.
Your competitors are still writing emails manually. You’re running AI death matches.
Who do you think wins?