Cold Email Subject Line Generator
Generate 10 high-converting subject lines in different styles. Questions, curiosity hooks, direct pitches, personalized lines, and number-based angles.
Subject Line Best Practices
Keep subject lines under 50 characters — they display fully on mobile.
Use the recipient's first name or company for instant personalization.
Questions outperform statements. They trigger curiosity and engagement.
Avoid ALL CAPS, excessive punctuation (!!!), and spam trigger words.
Lowercase subject lines feel casual and human — they stand out in busy inboxes.
A/B test at least 2-3 subject lines per campaign to find what resonates.
Match the subject line to the email body. Clickbait kills trust.
Numbers and specifics ("3x", "10 hours") increase open rates by up to 20%.
Frequently Asked Questions
Subject Lines Won't Help If You're In Spam
Even the best subject lines are worthless if your emails never reach the inbox. ColdRelay handles domains, DNS, mailboxes, and dedicated IPs so you land where it matters.
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