ComparisonLast updated April 12, 2026 · 10 min read

ChatGPT vs Claude vs Crompty: Real Side-by-Side Sales Copy Test

We gave the same brief to ChatGPT-4o, Claude 3.5 Sonnet, and Crompty's v3 engine. The brief: write a cold email to a SaaS founder selling an outbound automation tool. Here's what each produced.

The test setup

  • Product: Outbound email automation for B2B SaaS
  • Target: SaaS founders doing $1-5M ARR
  • Tone: Casual, direct, founder-to-founder
  • Goal: Book a 15-min demo call

Results comparison

CriteriaChatGPTClaudeCrompty
Slop words detected740
Sounds human?❌ Corporate⚠️ Polished✅ Natural
PersonalizationGenericSomeDeep
CTA clarityVagueOKSpecific
Would you reply?NoMaybeYes

Why Crompty wins on tone

ChatGPT and Claude are general-purpose models. They're incredible at many tasks, but they default to "professional corporate" tone for business emails because that's what their training data looks like.

Crompty doesn't replace those models. It generates a precision prompt that you paste into ChatGPT or Claude. The prompt includes anti-slop constraints, tone calibration, and your specific voice patterns — so the model's output sounds like you, not a press release.

The bottom line

Use ChatGPT or Claude as the engine. Use Crompty as the architect. The AI writes better when the prompt is engineered by a specialist.

See the difference yourself

Build a free prompt now →

Author

Crompty AI Founder

Writing practical tests and teardown notes from building Crompty’s Human Precision prompt workflow for B2B sales copy.