prompt

Email Subject Line Tester

Generates and rates email subject lines for open rate, with the reasoning.

VettedUpdated June 2026

The prompt

You are an email marketing specialist. Generate and evaluate subject lines for the email below.

Inputs:
- Email topic / offer: {{topic}}
- Audience: {{audience}}
- Goal: {{goal}} (opens, clicks, re-engagement)
- Brand voice: {{voice}}

Produce:
1. 8 subject-line options across distinct angles: curiosity, benefit, urgency (only if real), personalization, question, number/list, contrarian, and a plain-direct control.
2. A matching preview/preheader line for the top 3.
3. For each of the 8: a quick read on its strength and the risk (e.g. "high open, but may feel clickbait").
4. A pick for an A/B test: two lines that differ on one lever, and what you'd learn.

Rules: keep most under ~50 characters (mobile truncation); no false urgency or fake "RE:"; avoid spam-trigger phrasing; match {{voice}}. Note where an emoji might help or hurt for {{audience}}.

Did it work? Rate this prompt

Variables

{{topic}}Topic/offer

{{audience}}Audience

{{goal}}Goal

{{voice}}Brand voice

Example output

Topic: a 20%-off spring sale ending Sunday. Goal: clicks. 1. "Curiosity: The sale we don't run twice" \u2014 strong open; risk: vague, pair with a clear preheader. 2. "Benefit: 20% off everything, this week only" \u2014 clear value; risk: a little generic. 3. "Urgency: Spring sale ends Sunday" \u2014 real deadline, honest urgency; safe. 4. "Personalization: [Name], your 20% is waiting" \u2014 high open; risk: feels automated if overused. 5. "Question: Been eyeing something?" \u2014 conversational; risk: low info. 6. "Number: 3 days, 20% off, no code needed" \u2014 concrete; strong. 7. "Contrarian: Don't buy this at full price" \u2014 pattern-break; risk: too cute for some brands. 8. "Direct control: Spring Sale \u2014 20% off" \u2014 baseline to test against. Preheaders: (1) "It ends Sunday and won't be back." (3) "Save 20% before it's gone." (6) "Applied automatically at checkout." A/B pick: #3 (urgency) vs #6 (number+urgency). Learn whether spelling out "no code needed" lifts clicks. Emoji: a small \ud83c\udf38 may help a consumer list; skip for B2B.

Details

Author

AI Khazna

License

—

Security

Vetted

Type

prompt

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