Email Subject Line Tester
Test your email subject lines before sending. Get instant analysis on length, power words, spam risk, readability, and see how it looks in real inboxes.
Test Your Email Subject Line
Enter your subject line and get an instant score with detailed feedback.
Subject Line Testing Tips
Test Multiple Variations
Don't settle for your first draft. Write 5-10 variations and score each one to find the strongest option.
Check Mobile Preview
Over 60% of emails are opened on mobile. Make sure your subject line isn't truncated on smaller screens.
Avoid Spam Triggers
Words like "FREE" in all caps, excessive punctuation, and misleading claims can send you straight to spam.
Use Power Words Wisely
Urgency, curiosity, and benefit-driven words boost open rates, but don't overdo it -- balance is key.