100 subject line formulas organized by goal, plus a test tracker to improve open rates.
What This Is: 100 subject line formulas by goal (curiosity, benefit, urgency, social proof) plus an A/B testing tracker to systematically improve open rates.
warningWhy You Need This
The Hustle tested subject lines relentlessly until they knew what made people open.
Most founders write subject lines in 30 seconds and wonder why open rates stall.
This swipe file gives you proven formulas to test and a tracker to learn what works for your audience.
checklistHow to Use This Swipe File
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Pick Your Goal: Curiosity, urgency, benefit, or social proof.
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Choose 2-3 Formulas to Test: Match formulas to your content.
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Write Variants: Customize the template for your email.
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Run A/B Tests: Test one variable at a time.
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Log Results: Track outcomes in the A/B test tracker.
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Double Down on Winners: Reuse what works without burning it out.
dashboardWhat's Included
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100 Formulas by Goal: Curiosity, benefit, urgency, social proof, and more.
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A/B Testing Tracker: Log variants, open rates, and winners.
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Best Practices: What to test, what to avoid, and how to read results.
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Case Study Example: Real test outcomes and learnings.
Pro Tip: Save the subject lines that make you open emails and reverse-engineer the pattern.
Mid-week tests give cleaner data than Monday or Friday sends.
Avoid spam trigger words and excessive punctuation.