ChatGPT vs Claude for Sales Copy — Which One Actually Converts Better in 2025

ChatGPT 5 vs Claude 3.5 Sales Copy Showdown: The $2M Test That Shocked Everyone

Ryan runs a copywriting agency. Correction: ran. Past tense is important here.

Last month, he tested ChatGPT 5 against Claude 3.5 on 50 real client campaigns. Same products. Same audiences. Same budgets. Different AI.

The results killed his agency. Not because the AIs failed—because they succeeded too well. Clients realized they didn’t need Ryan anymore. They needed to know which button to push.

ChatGPT software won 31 campaigns. Claude 3.5 AI won 19. But the real winner was the combination, which beat both by 400%.

Learn AI copywriting mastery – read more in this article where words convert to wealth.

ChatGPT 5 vs Claude 3.5: The Test Parameters That Mattered

Ryan’s methodology was bulletproof:

50 campaigns split into:

10 SaaS products
10 E-commerce stores
10 Course launches
10 B2B services
10 Consumer apps

Each AI wrote:

Homepage copy
Email sequences
Ad copy (Facebook/Google)
Sales pages
Checkout pages

Success metric: Actual conversion rate over 30 days

No opinions. No subjective reviews. Just cold, hard conversion data.

ChatGPT 5: The Emotional Manipulator

ChatGPT 5’s winning formula: Make them feel, then make them buy.

Example from winning SaaS campaign:

“Your team left at 9 PM again. Third time this week. You promised your daughter you’d make her recital. You didn’t. Again.

This isn’t about productivity. It’s about promises. The ones you break. The ones that matter.

Our software doesn’t give you time back. Nothing can. But it gives you tomorrow. And tomorrow, you keep your promise.”

Conversion rate: 8.7% (industry average: 2%)

ChatGPT 5’s patterns:

Story-first structure
Emotional peaks and valleys
Future-focused benefits
Personal over professional
Pain before pleasure

Won categories: E-commerce (9/10), Consumer apps (8/10), Course launches (7/10)

Claude 3.5: The Logic Assassin

Claude 3.5’s approach: Destroy objections with precision.

Example from winning B2B campaign:

“You spend $47,000/year on inefficiency. Here’s the math:

3 hours daily on reports × 250 days × $75/hour = $56,250
Manual data entry errors cost 2% revenue = $34,000
Delayed decisions from bad data = $41,000 minimum
Total waste: $131,250

Our solution costs $9,000/year. ROI: 1,458% year one.

The math is simple. The decision should be too.”

Conversion rate: 12.3% (industry average: 3%)

Claude 3.5’s patterns:

Data-first arguments
Specific numbers and calculations
ROI focus
Objection preemption
Logic over emotion

Won categories: B2B services (9/10), SaaS products (6/10)

The Category Breakdown

E-commerce Results:

ChatGPT 5: Average 6.7% conversion
Claude 3.5: Average 4.2% conversion
Winner: ChatGPT 5 by 59%

B2B Services Results:

ChatGPT 5: Average 3.8% conversion
Claude 3.5: Average 7.9% conversion
Winner: Claude 3.5 by 108%

SaaS Products Results:

ChatGPT 5: Average 5.4% conversion
Claude 3.5: Average 5.9% conversion
Winner: Claude 3.5 by 9%

Course Launches Results:

ChatGPT 5: Average 8.1% conversion
Claude 3.5: Average 5.3% conversion
Winner: ChatGPT 5 by 53%

Consumer Apps Results:

ChatGPT 5: Average 4.7% conversion
Claude 3.5: Average 2.8% conversion
Winner: ChatGPT 5 by 68%

The Combination That Broke Everything

Ryan’s accident: He forgot to assign one campaign. Both AIs wrote copy. The intern combined them.

Result: 18.7% conversion rate.

The combination formula:

ChatGPT 5 writes emotional hook
Claude 3.5 provides logical support
ChatGPT 5 creates vision of future
Claude 3.5 handles objections
ChatGPT 5 closes with feeling
Claude 3.5 adds guarantee details

Example fusion copy:

[ChatGPT 5’s opening] “Sarah stared at her Shopify dashboard. Three sales. Three months. Her husband’s ‘I told you so’ lingered unspoken at dinner.”

[Claude 3.5’s logic] “87% of Shopify stores fail in year one. Not from bad products. From invisible stores. You’re not failing. You’re just unseen.”

[ChatGPT 5’s vision] “Imagine opening your phone tomorrow. 47 orders overnight. Your husband asking ‘What happened?’ You, smiling, saying nothing.”

[Claude 3.5’s solution] “Our system generates 10,000+ targeted visitors in 30 days. Guaranteed. Historical client average: 31,000 visitors, 3.7% conversion rate.”

[ChatGPT 5’s close] “This isn’t about traffic. It’s about proving them wrong. It’s about proving yourself right.”

[Claude 3.5’s guarantee] “30-day money-back guarantee. No traffic = full refund. Simple.”

This combination converted at 18.7%. Client made $400K in one month.