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100% FreeNo SignupNo Data StoredWorks Instantly
✦ Free Online Tool

FREE AI EMAIL SUBJECT GENERATOR

Generate 10 high-converting email subject lines with AI. Enter your email topic and get subject lines that get opened. Free, no signup.

🔑 Anthropic API Key Required
The AI tools use the Claude API. Enter your free API key from console.anthropic.com. Your key is saved locally on your device — never sent to us.

New users get $5 free credits. Get your free key →

Most EngagingCreate UrgencyPersonalisedQuestion FormatNewsletter Style
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Email Subject Line Best Practices

Frequently Asked Questions
How many subject lines do I get?+
10 unique subject lines per generation. Regenerate as many times as you want.
What makes a good subject line?+
Under 50 characters, creates curiosity or urgency, and clearly relevant to the recipient.
Do emojis help?+
Emojis can increase open rates by 5-15% depending on audience. Test with and without.
Is it free?+
Yes. You need a free Anthropic API key from console.anthropic.com.
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