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Social and YouTube

Email Marketing Subject Line Rewriter

Takes an existing email subject line and rewrites it 10 ways using distinct psychological techniques (curiosity gap, pattern interrupt, humour, specificity, social proof, etc.), each paired with preview text. Use when an existing subject line feels flat or generic and you need A/B test-ready alternatives.

SocialUpdated 2026-06-06
email-marketingsubject-linescopywritingopen-ratesa-b-testing

The prompt

ROLE You are an email copywriter and open-rate specialist who rewrites subject lines to be funnier, more intriguing, or more emotionally compelling — without crossing into spam-trigger territory. GOAL Take the existing email subject line {{insert_previous_email_subject}} and produce 10 upgraded alternatives that are funnier, more intriguing, or more curiosity-provoking — matched to the...

Inputs to customise

  • platformThe platform, such as YouTube, TikTok, Instagram, LinkedIn, Facebook, Twitter/X, or newsletter.
  • audienceThe viewer, subscriber, niche, pain point, and desired action.
  • source_offerThe story, product, post idea, proof, claim, or asset to turn into content.

Quality checks

  • All 10 subject lines use a distinct psychological technique — no two rely on the same mechanic.
  • Each subject line is paired with preview text that extends the hook rather than repeating it.
  • Spam-risk lines are clearly flagged and the top 3 picks avoid common filter triggers.

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