Subject Line Optimizer
How it works
Two modes. One goal: more opens.
Pick a starter prompt or describe your campaign. The AI generates 5-8 subject line variations, each with a different angle or strategy.
Paste a subject line you've written. Get a critique, issues flagged, and improved alternatives with before-and-after comparisons.
Every variation comes with its strategy tag and predicted engagement. Pick two for your next A/B test, which means no more guessing.
Try it now
Write better subject lines
Every variation has a strategy. We'll share not just what to write, but also why it works and share strategies like
Curiosity
"The one thing most marketers get wrong"
Urgency
"Ends tonight at midnight"
Social Proof
"2,847 people already signed up"
Direct Benefit
"Save 5 hours this week"
FOMO
"Only 12 spots left"
Question
"Ready to double your opens?"
Number/List
"7 templates that convert"
Personal Relevance
"[Name], your report is ready"
Stop staring at a blank subject line
Generate multiple variations in 3 seconds. Each has a different strategy, so you can A/B test with confidence. It's free to use in either mode: generate or optimize.
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