Test your email subject lines for spam triggers, optimal length, and open rate potential before you hit send.
Enter your email subject line to get instant feedback on its effectiveness.
Write subject lines that get opened
Aim for 30-50 characters. Mobile devices cut off longer subject lines.
Words like "FREE," "Act Now," and "Limited Time" can trigger spam filters.
Give readers a reason to open. Questions and incomplete thoughts work well.
Specific numbers and details outperform vague claims. "7 Tips" beats "Some Tips."