Subject Line Tester
Test your email subject lines to boost open rates and avoid the spam folder.
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Try MailerLite FreeWhy Subject Lines Matter
Your subject line is the first thing a recipient sees. A strong subject line makes them open the email, while a weak or spammy one sends your email straight to the trash.
Best Practices for Subject Lines
- Keep it short: Mobile devices cut off subjects after about 40-50 characters. Get to the point quickly.
- Avoid spam words: Words like "Free", "$$$", "Urgent", or ALL CAPS trigger spam filters.
- Use numbers and questions: Numbers stand out in a sea of text, and questions create a curiosity gap that encourages opens.