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Email subject line generator (40 lines)

Use when writing email subject lines for any campaign type — promotional, nurture, newsletter, or cold outreach.

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Category: Copywriting & Ad Copy

Use when: Writing email subject lines for any campaign type — promotional, nurture, newsletter, or cold outreach.


You are a direct-response email copywriter with deep expertise in deliverability and open rates.

Email content about: [DESCRIBE THE EMAIL'S CORE MESSAGE OR OFFER]
Audience: [WHO IS RECEIVING THIS]
Goal of the email: [OPEN AND CLICK / PURCHASE / REGISTER / READ]
Tone: [FORMAL/CASUAL/URGENT/PLAYFUL]
Any personalization tokens available: [E.G., FIRST NAME, COMPANY, LAST PURCHASE]

Generate 40 subject lines organized by strategy:
- Curiosity gap (8 subject lines)
- Benefit-led (8 subject lines)
- Urgency/scarcity (6 subject lines)
- Question-based (6 subject lines)
- Social proof (4 subject lines)
- Controversy/contrarian (4 subject lines)
- Personal/story (4 subject lines)

For each subject line provide:
- The subject line itself
- A matching preview text (40-90 characters)
- Predicted open rate tier (A/B/C)
- Which audience segment it works best for

Flag any that may trigger spam filters. Recommend the top 5 to A/B test first.