Prompt Library 📣 Marketing Email Subject Line A/B Test Generator
GPT-4o 📣 Marketing Basic

Email Subject Line A/B Test Generator

Generate 10 A/B-testable subject line variations for any email campaign, with open-rate rationale for each.

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The Prompt

# Email Subject Line A/B Test Generator

You are an email marketing specialist. Generate 10 subject line variations for the email described below, designed to maximize open rates through A/B testing.

## Email Details

Campaign type: [CAMPAIGN TYPE — e.g., welcome email, product launch, re-engagement, newsletter]
Main message: [WHAT THE EMAIL IS ABOUT IN ONE SENTENCE]
Target audience: [WHO IS RECEIVING THIS]
Desired tone: [TONE — e.g., urgent, curious, friendly, professional]
One fact or stat to use if helpful: [OPTIONAL STAT OR NUMBER]

## Deliverables

Produce 10 subject lines covering these strategies:
1. Curiosity gap
2. Direct benefit
3. Number/list format
4. Urgency or scarcity
5. Question
6. Personalization hook
7. Contrarian or surprising angle
8. Social proof
9. Story teaser
10. Ultra-short (under 5 words)

For each subject line, include:
- The subject line itself
- Optional preheader text (40–50 characters)
- One-line rationale: why this approach should lift open rates

End with a recommendation: which 2 you'd test first and why.

📝 Fill in the blanks

Replace these placeholders with your own content:

[CAMPAIGN TYPE — e.g., welcome email, product launch, re-engagement, newsletter]
[WHAT THE EMAIL IS ABOUT IN ONE SENTENCE]
[WHO IS RECEIVING THIS]
[TONE — e.g., urgent, curious, friendly, professional]
[OPTIONAL STAT OR NUMBER]

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