📣 Marketingbeginneremail-marketingsubject-linesopen-ratecopywriting

Write Email Subject Lines That Get Opened

Generate 20 email subject line variations covering every proven strategy — curiosity, urgency, personalization, data, and more.

The Prompt

prompt.txt
Write 20 email subject lines for the following email. Cover these strategies:
1. Direct (what's inside, no tricks)
2. Curiosity gap (they need to open to get the answer)
3. Number/list (specific and concrete)
4. Personal/second person (uses 'you' or 'your')
5. Urgency/deadline (time-sensitive)
6. Question
7. Counterintuitive/surprising claim
8. Social proof
9. Fear of missing out / loss aversion
10. Emoji (1 version with, 1 without to A/B)

For each subject line, add a preview text suggestion (40 chars).

Email content: [WHAT IS THIS EMAIL ABOUT]
Audience: [WHO IS RECEIVING THIS]
Goal: [WHAT DO YOU WANT THEM TO DO]
List type: [NEWSLETTER / COLD / WARM / TRANSACTIONAL]

Example Output

20 subject lines: top performer predicted is the counterintuitive claim 'Your most expensive LLM might be your worst.' Preview text: 'We analyzed 50M API calls to find out.' Also includes a curiosity gap ('The model everyone's switching to in 2026'), urgency ('Pricing changes tomorrow'), and 4 A/B-ready pairs.

FAQ

Which AI model is best for Write Email Subject Lines That Get Opened?

GPT-4o — strong at high-volume copy variations. Claude for more nuanced hooks.

How do I use the Write Email Subject Lines That Get Opened prompt?

Copy the prompt, replace the [BRACKETED] placeholders with your specific information, and paste into your preferred AI assistant (ChatGPT, Claude, Gemini, etc.). 20 subject lines: top performer predicted is the counterintuitive claim 'Your most expensive LLM might be your worst.' Preview text: 'We analyzed 50M API calls to find out.' Also includes a curiosity gap ('The model everyone's switching to in 2026'), urgency ('Pricing changes tomorrow'), and 4 A/B-ready pairs.