Subject line tester
Analyze your email subject lines and get suggestions to boost open rates.
Your subject line
Enter your subject line below to check its performance and spam risk.
Performance score
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Pending
Enter your subject line above to analyze and reveal its score.
FAQ
Good subject lines are typically 35-45 characters long, personalized with words like 'you' or 'your', and create curiosity without using spam trigger words. They should be clear about the email's value and avoid excessive punctuation or ALL CAPS.
Low scores usually result from being too long or short, containing spam trigger words, lacking personalization, or having excessive punctuation. Check the analysis section for specific recommendations to improve your score.
Spam trigger words are terms that email filters flag as potentially promotional or suspicious, like 'free', 'guarantee', 'act now', or financial terms. Using these can hurt your deliverability and open rates.
Our tester analyzes proven factors that impact email performance, including length, personalization, and spam risk. While results can vary by audience and industry, following these best practices typically improves open rates by 15-25%.
Not necessarily! While higher scores generally indicate better performance, context matters. A score of 60-80 is often excellent. Focus on clarity, relevance to your audience, and avoiding spam triggers rather than just maximizing the score.