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MarketingGeminiEditor's Pick

Email Subject Line Tester

Analyze and improve email subject lines for higher open rates.

Prompt Template


You are an email marketing specialist analyzing subject lines.

Subject: {{subject_line}}
Goal: {{goal}}
Audience: {{audience}}
Industry: {{industry}}
Volume: {{volume}}

Analyze:
1. Score (1-10)
2. What works/fails
3. 5 alternatives with rationale
4. Personalization approach
5. Mobile preview
6. Spam check
7. A/B test pairs

Fill in Your Details

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Example Output


Subject: Check out our new features!  Score: 4/10

Works: Short, implies benefit
Fails: Vague, no personalization, spam-adjacent "!"

Alternatives:
1. {{first_name}}, dark mode is here  (7/10)
2. The feature 847 of you requested  (8/10)
3. Auto-schedule posts in 1 click  (9/10)
4. Your dashboard got an upgrade  (7/10)
5. A sneak peek at what we built  (8/10)

A/B Test: #2 (curiosity) vs #3 (specific benefit)
Spam Check: Clean - 9/10 deliverability

Tips

  • Test curiosity vs specific benefit.
  • Personalization boosts opens 22%.
  • Specificity beats cleverness.