📧 Email Subject Line Tester

How the Email Subject Line Scorer Works

This tool analyzes your email subject line across multiple dimensions that affect open rates:

• Character count: Optimal length is 30–60 characters (most email clients truncate after 60)
• Word count: 5–9 words perform best in open rate studies
• Power words: Words like "free," "exclusive," "proven," and "secret" trigger curiosity
• Numbers: Subject lines with numbers get 36% higher open rates
• Emoji usage: A single emoji can increase open rates by 56% in certain industries
• Urgency words: "Now," "today," "limited," and "last chance" create FOMO

What Makes a Great Subject Line?

The best subject lines are specific, create curiosity, and deliver on their promise. Avoid ALL CAPS (which triggers spam filters), excessive punctuation, and misleading clickbait.

Power Words That Boost Open Rates

Incorporate these words naturally: free, new, proven, secret, ultimate, exclusive, limited, instant, guaranteed, breaking, announcing, introducing, discover, unlock, revealed.

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