Free Tool

Email Subject Line Generator

Generate 5 compelling subject lines that boost your email open rates. Just paste your email content or describe its purpose.

The more context you provide, the better the subject lines.

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Tips for Great Subject Lines

Keep it short

Aim for 6-10 words or 40-60 characters for best display across devices.

Create curiosity

Hint at valuable content without giving everything away.

Be specific

Vague subjects get ignored. Tell readers exactly what they'll get.

Avoid spam triggers

Skip ALL CAPS, excessive punctuation, and words like "FREE" or "URGENT".

Want more power?

This subject line generator is just the beginning. The Aeralis Gmail add-on brings AI email generation directly into your inbox.

Multiple profiles with custom tones
Full email thread context awareness
Google Search & Maps grounding
Unlimited emails (Pro plan)
Works directly inside Gmail

Free tier includes 15 emails/month. No credit card required.

Frequently Asked Questions

Common questions about our subject line generator

How many subject lines do I get?

Each generation gives you 5 unique subject line options, each with a different approach - from curiosity-driven to benefit-focused.

What makes a good email subject line?

Good subject lines are clear, specific, and create curiosity or convey value. They should be 6-10 words (40-60 characters) and avoid spam trigger words.

Can I use these for marketing emails?

Absolutely! Our AI generates subject lines suitable for newsletters, promotional emails, cold outreach, and business communications.

Is this tool free to use?

Yes! You can generate up to 10 sets of subject lines per hour completely free. No account needed.

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